Application of Laser Raman Spectroscopy of Ferroelectric Nanomaterial BaTiO3 in the Design of Color Spotlight Products on Stage

Abstract

With the improvement of people’s material requirements, the demand for lighting materials is higher and higher. This study mainly discusses the application of the laser Raman spectroscopy of ferroelectric nanomaterial BaTiO₃ in the design of color spotlight products on the stage. Firstly, the effects of different electrospinning parameters on BaTiO₃ nanofibers were studied. Then, the samples were spun under the best spinning parameters and annealed at 600°C, 650°C, 700°C, and 750°C, and then the phase structure, morphology, and piezoelectric properties of the samples at four different annealing temperatures were characterized. In this study, the laser Raman signal converges to the incident slit of the monochromator through the lens. After grating splitting, the signal is obtained through CCD. Finally, the spectral curve is recorded by the computer-controlled data acquisition software winspec/32 and saved as an .spe file. The spectral data to be processed need to be smoothed. The luminescence intensity of BaTiO₃ with flower structure is weak, which is mainly caused by the different crystal forms of the matrix. By analyzing the content of each element, it is found that BA/Ti = 1/2, and it can be inferred that the proportion of BaTiO₃ and TiO₂ is about 6%. The XRD spectra of the samples obtained at different temperatures (−25, 0, 30, 50, and 70°C) corresponded to the standard card BaTiO₃ one-to-one, and no impurity peaks were found, indicating that the obtained samples are pure phases. This research will promote the application of nanomaterials in color spotlight products.

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

1. Introduction

The development of ferroelectric and piezoelectric materials is very rapid, and they have been widely used in electronic technology, laser technology, infrared detection technology, ultrasonic (microwave acoustic) technology, solid-state memory and display technology, and other engineering technical aspects. The twenty-first century is an era of rapid development of information technology. With the faster and faster renewal of scientific products, people have higher and higher dependence and requirements on information technology. As the traditional integrated circuit is close to the limit of “Moore’s law,” in order to pursue smaller scale and more efficient chip performance, the research of various nanomaterials and devices is constantly carried out. Among them, the optoelectronic devices and optoelectronic chips developed based on nanophotonics have great potential and will break through the limitations of the traditional electronic industry in the future. It will promote the development of social communication and manufacturing industry and affect people’s real life in all aspects.

As the most representative ferroelectric material with a simple perovskite structure, barium titanate is widely used in the field of electronic components. In recent years, with the continuous miniaturization of memory, drivers, capacitors, and other devices, as well as the rise of new flexible devices such as nanogenerators, the dielectric research of extreme size systems continues to receive attention. The research on the size effect and dielectric limit of barium titanate nanoparticles includes the preparation of ultrafine nanocrystalline materials and powder performance evaluation technology. The design and preparation of color spotlight products have important theoretical value and guiding significance. With the emergence of new ferroelectric materials and the development of thin film technology, the application of ferroelectrics in information storage, image display, and page editors in holography has also opened a new page. In recent years, the emergence of laser technology has brought about the rapid development of ferroelectric and piezoelectric transistors.

In the past, the application of ferroelectric materials mainly used their piezoelectricity, pyroelectricity, electro-optical properties, and high dielectric properties, and there were not many applications in ferroelectricity. Raman spectrum, also known as molecular fingerprint spectrum, has the characteristics of identifying substances. Porizka et al. believe that detecting F and other halogens by conventional techniques is a challenge. He introduced various methods for qualitative and quantitative analysis of fluorine by laser-induced breakdown spectroscopy (LIBS). In the experiment of LIBS, the detection of fluorine can be realized by atomic wires and molecules. He analyzed two groups of particles with different CaF₂, CaCO₃, and cellulose contents in his atmosphere. The fluorescence atomic line at 685.60 nm is related to the CAF signal, which proves the close relationship between them. Therefore, they determined the detection limits of two analytical signals. In addition, they estimated the conditions required to quantize F through CAF band signals. They studied the relationship between CAF signal and the change rate of the Ca and F content. Finally, a real CaF₂ crystal chip was prepared, and its surface was mapped by Raman and libsystems [1]. Wang et al. believe that laser Raman spectroscopy can be used to obtain the unique fingerprint of specific molecules and it is widely used in the identification of substances and the study of spectral line characteristics of molecular structure. The measurement of coalbed methane (CBM) content is the key to optimize fracture design in coalbed gas field exploration and development. They integrated the laser Raman spectroscopy system with the coiled tubing (CT) equipment used for downhole deployment of gas wells to accurately determine the CBM content on-site. The developed system can directly determine the CBM content at a specific location of the target layer. The tracer test characteristics enable the system to quickly detect the composition and content of downhole gas. The real-time detection data are transmitted to the computer on the ground through cable, and processed by baseline correction algorithm and data enhancement algorithm. Fourier transform and wavelet transform are used to identify Raman spectral lines, while Raman spectral analysis is used to determine the CBM content. In addition, the integrated laser Raman spectrum CT system has flexible operation and strong field operability, and it is suitable for complex and high-risk wells [2]. Asami et al. believe that gas-phase spectroscopy is a powerful tool to detect the basic chemical structure and properties of solvent-free molecules. They developed a gas-phase resonance Raman spectroscopy combined with infrared laser ablation droplet beam. In order to prove the potential of this method, they applied this method to myoglobin, a heme protein, and clarified its structure in the gas phase and aqueous solution. They compared the experimental spectrum with the calculated spectrum of stable heme structure to determine its structure [3]. Gao et al. believe that laser Raman spectroscopy is an in situ nondestructive rapid detection technology, which has important application prospects in the field of explosive analysis and detection. He analyzed the advantages and limitations of various laser Raman spectroscopy techniques. The laser Raman spectra of TNT, CL-20, HMX, PETN, and RDX were compared [4]. Choi et al. carried out quantitative Raman analysis of geological mixed samples with different matrices. In order to compensate the matrix effect in Raman shift, laser-induced breakdown spectroscopy (LIBS) was analyzed. Raman spectra show that the mixed samples contain geological materials. However, due to the weak signals of Raman shift, interference, and strong matrix effect, the analysis of mixtures containing different matrices is inaccurate. On the other hand, LIBS has high accuracy in the quantitative analysis of atomic carbon and calcium in mixed samples. For the mixture of calcite and gypsum, the coefficient of atomic carbon measured by LIBS is 0.99, while the signal measured by Raman spectroscopy is less than 0.9. Therefore, they first used Raman spectroscopy to obtain the geological components of the mixed samples and then conducted LIBS-based quantitative analysis of the Raman spectroscopy results to construct a high-precision univariate calibration curve [5]. Raman spectra reflect the vibration and rotation of molecules in matter. Due to the interaction between photons and molecules, a characteristic frequency shift characterizing the difference of molecular vibration and rotation energy levels is generated. From this, we can judge the chemical bonds and molecular structure contained in the molecule. The color or brightness of the designed lantern can be adjusted according to the Raman spectrum.

The continuous development and innovation of the lantern industry plays a good role in the economic promotion of places where folk culture is concentrated and lantern is made. The particle size is controlled by the in situ surface modification of organic matter and the surface-coated carbon layer. The microwave absorbing materials are studied by studying the structure and morphology of carbon-coated barium titanate and the dielectric and electromagnetic properties of the composites with epoxy resin. In this article, barium titanate nanomaterials will be prepared, and the generation of various light waves will be measured by laser Raman spectroscopy. Through the application of colorful lighting design on the stage, the whole stage can look more beautiful.

2. Application of Laser Raman Spectroscopy in the Design of Colored Spotlights on the Stage

2.1. Ferroelectric Nanomaterials

With the rapid development of preparation methods of nanomaterials and microwave technology (microwave technology refers to electromagnetic waves with an average wavelength between 0.1 m and 1 m, which can generate high-frequency electromagnetic fields, and the molecules in the dielectric material will go to different situations in the electromagnetic field with the continuous change of their frequencies), the combination of microwave technology and chemical reduction to prepare noble metal nanoparticles has become a more convenient and faster preparation method. When the dipoles change their mutual orientation at a high frequency, the energy generated by friction and motion between molecules will be converted into heat energy, the temperature of the reaction system will rise rapidly, and the reduction rate of precursors will accelerate. The large-scale electrical equipment can improve efficiency, but it will also increase the electrical stress on the materials in the equipment and it is easy to be damaged [6, 7]. Therefore, we need to develop new high dielectric composites to meet the electrical stress control requirements of large electrical equipment and promote the development of the electrical industry. In addition, high dielectric composites can also be used to prepare high-energy storage devices to meet the current social demand for energy. Energy storage devices made of high dielectric composites have high power density and have important application potential in aerospace, cutting-edge weapons, and electric vehicles. Barium titanate-based polymer composites studied in this paper are one of the most potential high dielectric composites. The development of such high dielectric materials with excellent properties is of great significance to accelerate the development of China’s national economy and enhance national security [8, 9].

2.2. Laser Raman Spectroscopy

It is generally believed that the structure and properties of the detected substance will not change during the SERS (surface-enhanced Raman spectroscopy) detection process. However, with the deepening of research, the chemical composition of the molecules adsorbed on the substrate surface has changed through the local surface plasmon resonance of laser irradiation, which can be detected by Raman spectroscopy. If light is irradiated on the surface of the material, a small part of the light may be scattered on the surface of the material [10]. The ultrafast nonlinear process is the process of the interaction between the ultrafast laser and the nonlinear material. At this time, the relationship between the polarization intensity P and the incident photoelectric field E is$$\begin{array}{}\text{(1)}& P={\epsilon }_0{\chi }^{1}E+{\epsilon }_0{\chi }^2:EE+{\epsilon }_0{\chi }^3⋮EEE+\cdots =P^1+P^2+P^3+\cdots \text{,}\end{array}$$where ε₀ is the dielectric constant in vacuum; P⁽¹⁾, P⁽²⁾, and P⁽³⁾ are the first-, second-, and third-order polarization intensities, respectively; χ⁽¹⁾, χ⁽²⁾, and χ⁽³⁾ are the first-order, second-order, and third-order polarizability tensors, and the second-order and above polarizability tensors are the basic parameters that characterize the nonlinear interaction between light and matter [11].

Under paraxial approximation, the thin lens can be represented by a transmittance function, namely,$$\begin{array}{}\text{(2)}& t_L{x}_1,y_1=P{x}_1,y_1\cdot \exp -\frac{ik}{2f}{x}_1,y_1\text{,}\end{array}$$where i represents the imaginary unit and k is the wave vector of light. After a monochromatic plane wave passes through a thin lens, the complex amplitude distribution of its light field is represented by ${U_1}^{\prime }{x}_1,y_1$. The size of the light field after passing through the thin lens is the product of the incident light field and the transmittance function of the lens, namely [12],$$\begin{array}{}\text{(3)}& U_{\mathit{1}}^{\prime }{x}_1,y_1=U_1{x}_1,y_1\cdot t_L{x}_1,y_1\text{.}\end{array}$$

From the Fresnel diffraction integral, we can get [13]$$\begin{array}{}\text{(4)}& Ux,y=\frac{\exp ikf}{i\lambda f}{\displaystyle \int }{{\displaystyle \int }}_{-\infty }^{\infty }{U}_{\mathit{1}}^{\prime }{x}_1,y_1\cdot \exp ik\frac{{x-x_1}^2+{y-y_1}^2}{2f}\mathrm{d}{x}_1{y}_1\text{.}\end{array}$$

The complex amplitude of the light field at the focal plane is$$\begin{array}{}\text{(5)}& Ur,\theta =\frac{a}{ir}\exp ikf\exp \frac{ik{r}^2}{2f}{J}_1\frac{akr}{f}\text{.}\end{array}$$

At this time, the light intensity detected at the focal plane is as small as$$\begin{array}{}\text{(6)}& I=Ur,\theta \cdot U\ast r,\theta \text{.}\end{array}$$

Assuming that the incident light field is a Gaussian distribution field with a beam waist radius of ω0 before the objective lens is focused, the electric field intensity $E_{inc}\alpha$ can be expressed as [14]$$\begin{array}{}\text{(7)}& E_{inc}\alpha =\exp \frac{-f^2{\sin }^2\alpha }{{\omega }_0^2}\text{.}\end{array}$$

The signal field generated by nonlinear polarization in a uniform and isotropic medium is represented by the wave equation as$$\begin{array}{}\text{(8)}& \nabla \times \nabla \times Er,t+\frac{n^2}{c^2}\frac{\partial Er,t}{\partial t^2}=-\frac{4\pi }{c^2}\frac{P^{NL}r,t}{\partial t^2}\text{,}\end{array}$$where $P^{NL}r,t$ represents the nonlinear polarizability, n is the refractive index of the medium, and c is the speed of light in vacuum [15]. Then, the third-order nonlinear polarization intensity of the sample and the CARS signal field distribution can be expressed as$$\begin{array}{}\text{(9)}& \begin{array}{c}{P}^{NL}r,t=P^{3}r\exp -i{\omega }_{\mathrm{C}\mathrm{A}\mathrm{R}\mathrm{S}}t+c.c\text{,}\\ E_{\mathrm{C}\mathrm{A}\mathrm{R}\mathrm{S}}r,t=E_{\mathrm{C}\mathrm{A}\mathrm{R}\mathrm{S}}r\exp -i{\omega }_{\mathrm{C}\mathrm{A}\mathrm{R}\mathrm{S}}t+c.c\text{.}\end{array}\text{.}\end{array}$$

The weight factor of the smoothing window is obtained by the least squares fitting method, and its definition is$$\begin{array}{}\text{(10)}& X_i^{\ast }=\frac{{\displaystyle \sum }_{j=-r}^r{X}_{i=j}{W}_j}{{\displaystyle \sum }_{j=-r}^r{W}_j}\end{array}$$where $X_i^{\ast }$ represents the smoothed spectral data vector; $W_j$ represents the weighting factor of the moving window; and the weighting factor is determined by the window size [16, 17].

For the evaluation of the spectral smoothing effect, this article uses the signal-to-noise ratio (SNR) and root mean square error (RMSE) of the spectrum as evaluation parameters. Among them, the definition of root mean square error is divided into [18]$$\begin{array}{}\text{(11)}& \mathrm{R}\mathrm{M}\mathrm{S}\mathrm{E}=\sqrt{\frac{{\displaystyle \sum }_{i=1}^n{x_{i}n-{\overline{x}}_{i}n}^2}{n}}\text{,}\end{array}$$where x(n) is the original spectral signal and n is the number of spectral bands [19].

In the process of light propagation, when a beam of monochromatic light illuminates the sample, reflection, transmission, and scattering generally occur. Most of the light will be reflected or transmitted, and only a small part of the light will be scattered, as shown in Figure 1. The intensity of scattered light is proportional to the number of molecules irradiated by the incident light. Therefore, the intensity of tracking scattering and antitracking are proportional to the number of molecules in the ground state energy level and the excited state energy level, respectively [20].

[figure(s) omitted; refer to PDF]

2.3. Color Spotlight Design

The frame of the color spotlight control system on the stage is shown in Figure 2. The intelligent terminal control software can be an executable program developed based on Windows platform PC, or an application program developed based on Android or Los platform mobile phone, tablet, and other devices. LabVIEW is a program development environment, which uses the graphical editing language G to write programs, and the generated programs are in the form of block diagrams. The control software (host computer software) in this article is developed and implemented based on LabVIEW software on Windows platform PC. The wireless LED color lamp controller is the core component of the wireless LED color lamp control system. It mainly includes high-performance single chip microcomputer, Bluetooth serial port slave module, LED color lamp driving circuit, and photosensitive resistance signal conditioning circuit. Its main function is to collect the temperature, humidity, brightness, and other data of current home environment in real time through temperature and humidity sensor and photosensitive resistance, send the temperature and humidity data to the upper computer software, receive the instructions of the upper computer, and control the LED color lights to work in different modes according to the brightness of the current home environment [21].

[figure(s) omitted; refer to PDF]

2.4. Experimental Materials and Instruments

The main materials used in the experiment are titanate nanotubes, titanate fibers, barium hydroxide, barium nitrate, strontium hydroxide, and so on.

Raman spectrometer is an analytical instrument used in the field of energy science and technology. The Raman spectrometer used in the experiment is LabRAM HR Evolution microconfocal Raman spectrometer. The Raman spectrometer has three general laser wavelengths of 532 nm, 633 nm, and 785 nm, and the appropriate excitation wavelength can be selected according to the characteristics of the detected material. The light passes through a polarizer to generate polarized light, enters the microscope through optical equipment such as a plane mirror, illuminates the sample, and scatters with the sample material. The diffraction grating divides the Raman scattered light into Raman signals of different frequency bands, and finally, it is displayed the Raman spectrum on the computer terminal through a CCD detector [22, 23].

2.5. Preparation of Nanocrystalline Barium Titanate-Based Powder

In this article, because the nucleation and crystallization rate of barium titanate are controlled by controlling the reaction rate of tetrabutyl titanate, the next step of the reaction is to avoid high temperature sintering and obtain monodisperse barium titanate nanoparticles with good crystallization at low temperature. The raw materials, surfactant PVP (polyvinylpyrrolidone), solvent, and an appropriate amount of mineralizer required for the reaction are added into the single neck flask of the reactor in a certain proportion and put them into the single neck flask under reflux conditions. By preheating the silicone oil to 160°C, and then stirring and heating, after holding for 15 minutes to 4 hours, a light yellow sol containing stably dispersed titanate particles can be obtained in the solvent; after cooling, the excess deionized water (5–10 times the volume) sol is added to the sol to precipitate the nanocrystalline powder. After washing and drying, barium titanate nanopowder is obtained [24]. Horizontal electrospinning was used for spinning. Firstly, the effects of different electrospinning parameters on BaTiO3 nanofibers were investigated. Next, after spinning with the best textile parameters and annealing at four temperatures of 600°C, 650°C, 700°C, and 750°C, the phase structure and morphology of the samples were investigated at four different annealing temperatures [25, 26]. The list of drugs required in the preparation of BaTiO3 nanofiber precursor solution is shown in Table 1.

Table 1

List of drugs needed in the preparation of BaTiO₃ nanofiber precursor solution.

Name	Molecular formula	Molecular weight	Purity (%)
Barium acetate	(CH3COO)2Ba	255.21	≥99.0
Glacial acetic acid	CH3COOH	60.05	>99.5
Isopropyl titanate	C12H28O4Ti	284 22	≥95.0
Absolute ethanol	CH3CH2OH	46.07	≥99.7
Polyvinylpyrrolidone (PVP)	(C6HgNO)n	1300000	>99.0

2.6. Laser Raman Spectrum Test

The glass sample cell was sealed and taken out, and the barium titanate nanoparticles were analyzed and put into an electric furnace for 60°C water bath heating for 3 minutes. After heating, put the sample cell back to the sample rack, keep the original spectrometer operating parameters unchanged, conduct Raman spectrum data collection again, and heat the sample cell with thermal insulation property continuously and moderately with electric bellows while spectrum testing, and process the data before and after heating the sample. The effects of temperature on Raman scattering spectra in the two cases were compared [27, 28].

3. Laser Raman Spectroscopy in Stage Color Spotlight Product Design Results

Nanopowder has various properties, which is different from macro materials because of its huge surface area and high proportion of surface atoms. The relationship between nanoparticle size and surface atomic number is shown in Table 2.

Table 2

Relationship between nanoparticle size and surface atomic number.

Particle size (nm)	Number of atoms included	Surface atomic ratio (%)	Surface energy/total energy
10	30000	20	7.6
5	4000	40	14.3
2	250	80	35.3
1	30	99	82.2

We first performed XRD tests on the BaTiO₃ nanofibers obtained at four different spinning distances, and the test results are shown in Figure 3. Compared with the BaTiO3 standard card JCPDS NO. 75–2120, it is found that the fibers obtained at all distances have obvious diffraction peaks such as (110), (200), (211), and (200) [29]. Moreover, the positions of all diffraction peaks are consistent with the standard card, and there are no other impurity peaks. This shows that BaTiO3 nanofibers with pure perovskite-phase structure have been successfully obtained at all four spinning distances. At the same time, it can be seen that the diffraction peak intensities under the four different spinning distances are not much different, indicating that the spinning distance has no effect on the degree of crystallinity.

[figure(s) omitted; refer to PDF]

In order to study the influence of the synthesis temperature on the phase state and morphology of BaTiO₃, XRD tests were performed on it. The XRD test results at different temperatures are shown in Figure 4. The XRD spectra of the samples obtained at different temperatures (−25, 0, 30, 50, and 70°C) corresponded to the standard card BaTiO₃ one-to-one, and no impurity peaks were found, indicating that the obtained samples are pure phases.

[figure(s) omitted; refer to PDF]

Using barium oxalate and anatase TiO2 as raw materials, BaC₂O₄∙H₂O : TiO₂ : NaCl : KCl was mixed at a molar ratio of 1 : 2 : 20 : 20 and calcined at 870°C for 9 hours. The XRD pattern of the product is shown in Figure 5. The spectrum can be calibrated as pure phase BaTi₂O₅, JCPDS card No. 85–0476. The unit cell parameters are a = 9.410 Å, b = 3.930 Å, c = 16.892 Å, p = 103.03°.

[figure(s) omitted; refer to PDF]

The full spectrum of BaTiO₃/TiO₂ heterojunction and TiO₂ nanotube array XPS is shown in Figure 6. Compared with pure TiO₂, the XPS curve of BaTiO₃/TiO₂ heterojunction has two more peaks at 794.259 and 778.926 eV binding energy. By analyzing the content of each element, it is found that Ba/Ti = 1/2, which can be inferred the ratio of BaTiO₃ and TiO₂ is about 6%. The peak intensity of curve b to curve e changes continuously. It is found that as the concentration of Ba(NO₃)₂ increases, the hydrothermal reaction time increases, and the hydrothermal reaction temperature increases, and the intensity of the diffraction peak of TiO₂ is constantly decreasing, which shows that the degree of reaction between TiO₂ and Ba(NO₃)₂ is gradually increasing.

[figure(s) omitted; refer to PDF]

The precursor obtained after acid treatment has diffraction peaks at the 2θ24.5° and 28.8° diffraction angles, which are consistent with the (110) and (600) plane reflections of H₂Ti₂O₅. It proves that sodium ions are replaced by hydrogen ions. When the temperature reaches 500°C, it is completely transformed into anatase titanium dioxide. The diffraction peaks of the anatase phase after acid treatment change with temperature as shown in Figure 7.

[figure(s) omitted; refer to PDF]

The luminous intensity of a material is affected by its morphology and in the final analysis is caused by the difference of surface defects of various morphologies. The same applies to nanorods, nanoribbons, and spindle-shaped nanoparticles. Through comparison, it is found that compared with spindle-shaped nanoparticles and nanorods, TiO₂ : Eu⁺ nanoribbons have fewer surface defects and the best doping concentration is 8 mol%, so they have stronger luminous intensity. The change in the luminous intensity of the material is shown in Figure 8.

[figure(s) omitted; refer to PDF]

4. Discussion

With the advent of the era of industrial civilization, great changes have taken place in all aspects of people’s life and production. As a closely related material, conversion luminescence is also continuously developed with the development of science and technology. Compared with traditional quantum dot materials, fluorescent pigments have the advantages of low toxicity, high optical stability, high chemical stability, long service life, and narrow emission frequency band. Therefore, they have safety signs, backlight, color display source, and biological imaging. It has potential application value in solar cells and other fields. Infrared absorption spectrum is highly sensitive, but generally speaking, the analysis of mixtures is weak, and the spectra of mixtures overlap to a great extent. In practical application, the infrared absorption signal of gas often falls into noise, and the gas concentration will be measured directly by spectral absorption. In particular, it is very difficult to detect relatively low gas concentrations. Compared with gas colorimetric analysis and infrared spectroscopy, laser Raman spectroscopy has the characteristics of high speed, simplicity, and reproducibility, and it is nondestructive and quantitative. Raman spectroscopy distinguishes various substances from the molecular vibration and rotation spectra of substances.

From Raman spectra, important parameters reflecting molecular structure can be obtained, such as frequency shift, polarization state, and Raman intensity. Raman spectroscopy can detect solid, liquid, and gas targets. The photon detection used will not damage the sample. Therefore, Raman spectroscopy is one of the important methods to study the molecular structure of substances. In order to obtain fluorescent nanoparticles, the combination of light and nanomaterials has developed into a new research field.

The fabrication of iron ore nanotube array films has been regarded as a difficult problem since its discovery. However, the recently discovered one-dimensional nanostructure materials have a wide range of applications in the industrial field, hiding the great possibility of replacing thin film materials. In recent years, people are looking forward to the rapid development and application of one-dimensional nanomaterials with strong dielectric properties. At the same time, the tracking investigation of dielectric properties and dielectric phase transfer of ferroelectric nanotube arrays is also the most priority. The physical properties of nanocrystalline BaTiO₃ materials largely depend on their structural properties, but on the contrary, the crystal structure information can be further verified through the test of physical properties. In the size effect of BaTiO₃, dielectric constant and dielectric phase shift are the focus of research. By preparing dense ceramics or films, the dielectric and dielectric properties of the materials can be obtained by dielectric temperature spectroscopy, microdomain dielectric analysis, and its hysteresis loop test. In addition, when atomic force microscopy (AFM) is used to test dielectric properties, due to the direct contact of the probe with the sample, the force of the sample increases, and the sample needs a certain degree of mechanical strength. The particle sample is only attached to the substrate due to gravity. The position will move when touched and detected, and a true ferroelectric response cannot be obtained.

It is well known that the recombination of most electron-hole pairs is one of the main reasons for photocatalytic decomposition in the evaluation of photocatalytic reactions. Noble metal oxide systems are widely used to catalyze reactions due to their special contact interface structure and chemical and electronic characteristics [30]. After the catalytic modification of the noble metal, as a receiver of photogenerated electrons, the noble metal promotes the transport of the interface carrier in the composite system and allows the photogenerated electrons to accumulate on the surface of the metal. The photocatalytic performance of the titanium dioxide nanotube array is limited by the high recombination probability of the light-generating carrier. In order to improve the photocatalytic performance, there are many ways to modify titanium dioxide. For example, titanium dioxide nanotubes are compounded with a semiconductor that is consistent with the energy band, which effectively separates the preferred electrons and the electrons generated by light, and improves the utilization of incident light.

The properties of nanomaterials are greatly affected by their microstructure. If the sample is affected by mechanical force, the lead-free piezoelectric ceramic powder in the sample will produce strain under the action of stress, and the crystal structure will change to produce piezoelectric effect, and the output voltage of the sample will be produced. Therefore, the piezoelectric matrix used to make the power generation film has a great influence on its performance. This is an important aspect of the structure design of the composite power generation membrane. Although fossil energy is the main manpower to obtain energy, the amount of fossil energy buried is decreasing every day, and the development of renewable resources has become a hot spot. Scientists are also paying more and more attention to new energy materials. The microstructure of the material plays an important role in the characteristics of power generation materials. If the sample is affected by mechanical force, the piezoelectric matrix inside the sample will change the crystal structure under the action of stress, resulting in the piezoelectric effect and output voltage of the sample. Therefore, studying the changes in the internal phase structure of composite power generation materials is a very important method to study and explain the power generation performance of composite power generation materials. Similarly, the microscopic morphology of the sample is also an important method to illustrate the performance of the sample.

The energy storage density of an electrostatic capacitor is determined by the dielectric breakdown electric field strength and dielectric properties of the dielectric. A high dielectric constant of the dielectric material and a high dielectric breakdown electric field strength are required in order to obtain a capacitor with a high-energy storage density. Many candidate materials meet one of these conditions. For example, ferroelectric ceramics have a high dielectric constant, and polymers have a high dielectric breakdown electric field strength. However, large-scale storage and utilization of new energy requires new dielectric materials with high dielectric constant and dielectric strength. Therefore, the development of polymers or composites with high dielectric constants is an effective solution.

PVDF, which has excellent chemical resistance, environmental stability, and excellent processing characteristics, is an energy storage medium material. It can be used for piezoelectric sensors for space detection of small debris, electrostrictive membranes for orbital rainfall radars, etc. [31]. It has potential applications in the piezoelectric and thermoelectric fields. BaTiO3 ferroelectric ceramics have very high dielectric properties. The modified BaTiO₃/PVDF composite material is prepared by grafting long carbon chain organic phosphoric acid onto the surface. In order to obtain a high-energy storage density, it is expected to have both a high dielectric constant and a dielectric breakdown electric field strength. This composite material has the advantages of piezoelectric ceramics and polymers. It has excellent flexibility and handling properties, and its density is also reduced. It can easily realize the acoustic impedance matching of air, water, and biological tissues, and it is widely used in medical, sensing, measurement, and other fields.

Capacitors are characterized by high power density and fast response. However, the energy storage density is lower than that of batteries. The energy storage density of traditional dielectric capacitors is very low, but its output power density is the highest, and pulse devices need to store the smallest and highest energy. It is suitable for fields with high output power and discharge rate requirements. And it is used to improve the energy storage density of dielectric capacitors and the volume of the corresponding energy release time. The compatibility between inorganic nanoparticles and organic matrix is an important factor that affects the structure and properties of PVDF dielectric composite materials. In order to improve the compatibility of the inorganic nanoparticles and the organic matrix, the surface of the nanoparticles is chemically modified with organic substances to improve the dispersion of the nanoparticles in the PVDF matrix, and finally, the purpose of increasing the strength of the destructive electric field of the composite material can be achieved.

Nanophotoelectric material is a kind of nanomaterial that can convert light energy into electrical energy, chemical energy, or other kinds of energy. It can also emit light through the opposite process of the above conversion. According to the action of light, molecules, ions and solids absorb light, and electrons become excited state, causing charge transfer and realizing photoelectric conversion process. Ligands are usually electron supplying, but due to the lack of metal electrons on the surface of nanocrystals, they will produce recombination and hinder the above growth and aggregation. Surfactant molecules diffuse into the solvent to determine the solubility of nanocrystals. There are two types of SERS mechanisms. One is the electromagnetic enhancement of substances adsorbed on the surface of coarse metal by the excitation of surface plasmon. This type is called electromagnetic enhancement. Another type is the atomic clusters on the surface of crude metal and the material molecules adsorbed on them constitute the Raman-enhanced active electrode. The preparation of active substrate with good performance is the key to expand the research scope and application scope of SERS technology. In most cases, a small amount of surfactants play an important role in the growth rate. The idea of combining nanofibers and noble metal nanomaterials gives full play to their respective advantages. The SERS enhancement coefficient of precious metals is very high, and nanofibers have excellent ductility, high cost performance, and easy storage and use.

5. Conclusion

In this study, the possibility of laser Raman spectroscopy technology applied to the design and analysis of color spotlight products is discussed. A laser Raman spectroscopy detection experimental system is constructed under laboratory conditions for the purpose of studying the quantitative analysis of the pretreatment method of Raman spectroscopy data. Titanate nanofibers are precursors of titanium dioxide prepared by firing and heat treatment. With the increase in the sintering temperature, the pore volume of the product decreased, and the photocatalytic activity of the sample first increased and then decreased. The solvent environment was changed and the control of polymorphism and morphology was realized. On this basis, the effects of crystallization on crystal growth, phase transition, morphology control, and photocatalytic activity of titanium dioxide were explained. In this study, titanium dioxide with high photocatalytic activity was prepared by the heat treatment of titanate nanofibers. The effects of sintering temperature on microstructure and photocatalytic activity were studied. In future studies, other properties of titanium dioxide can be studied. In the future, the collected powder can be prepared by calcining the collected powder at a higher temperature.

Acknowledgments

This work was supported by the httpJiangsu University of Science and Technology under research topic Teaching research on “coordinated education” talent training mode of industrial design specialty, undergraduate education and teaching reform project in 2021. This work was supported by the Ministry of Education under research topic Research on the cultivation of innovation and entrepreneurship ability of industrial design undergraduates, a collaborative education project of industry university cooperation, which was launched by Neimenggu Zhongguancun energy alliance Circular Industrial Park Co., Ltd. in 2020. This work was supported by the Ministry of Education, under research topic research on countermeasures for improving the teaching quality of UI design course, a collaborative education project of industry university cooperation of in 2020, Zhongqiweiyun (Beijing) Technology Co., Ltd.

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