Photosensitive Layer Research Articles

Study of the effect of the thickness of the photosensitive layer of perovskite on its efficiency using SCAPS-1D software

Photovoltaic cells are the best way to convert solar energy into electrical energy by absorbing photons emitted by the sun. This paper presents the results of studies of the effect of the thickness of the absorbing layer of perovskite on the quantum efficiency of the solar cell, as well as on its efficiency. These results were obtained by modelling in the software product SCAPS-1D. Perovskite photovoltaic is getting to be a distinctly predominant option for the conventional solar cells achieving maximum efficiency of 22.1% and more. This work is concerned about the design and analyses of lead-based perovskite solar cell model with the architecture of TiO2/CH3NH3PbI3/spiro-OMeTAD. The analysis of solar cell architecture is done using the Solar Cell Capacitance Simulator (SCAPS). It is a computer-based software tool and is well adapted for the analyses of homo and heterojunctions, multi-junctions and Schottky barrier photovoltaic devices. This software tool runs and simulates based on the Poisson’s and continuity equation of electrons and holes. For this model, it is used to optimize the various parameters such as thickness, the defect density of absorber layer, doping concentrations (ND and NA) of Electron Transport Material (ETM) and Hole Transport Material (HTM)

Proliferative capacity of retinal progenitor cells in human fetal retina

Introduction: Retina is an innermost, delicate, and photosensitive layer of the eyeball, which is composed of 10 layers and 8 specialized cells which are involved in paramount function of the body like vision. Retinal neurogenesis commences from the layers of optic cup, which forms from optic vesicle. Progenitor cells are the tissue-specific cells which give rise to all different types of retinal cells. Progenitor cells in fetal retina proliferate at specific time during development of retina. Knowledge of the highest proliferative capacity interval of progenitor cells will be valuable for transplantation. Material and Methods: Twenty-eight fetuses of spontaneous abortions of 13th–40th week were collected from MGM Hospital after ethical and scientific approval of the institute. After fixation of fetuses, eyeballs were extracted and fixed in buffer solution. Sections were taken and the retina was treated with Ki-67 immunohistochemistry marker to observe proliferative capacity of retinal progenitor cells (RPCs). Seven groups (A to G) of 4 weeks were made and observations of each group were noted. Results: It was observed that the highest proliferative capacity of RPCs was in B group (17–20 weeks) and the highest proliferative capacity of RPCs was maximum at 19th week of gestation. Discussion and Conclusion: Characteristics of progenitor cells in retina are well studied. Their highest proliferation period can be utilized to make the procedure of transplantation more refined.

Floating-gate photosensitive synaptic transistors with tunable functions for neuromorphic computing

Synaptic devices that merge memory and processing functions into one unit have broad application potentials in neuromorphic computing, soft robots, and human-machine interfaces. However, most previously reported synaptic devices exhibit fixed performance once been fabricated, which limits their application in diverse scenarios. Here, we report floating-gate photosensitive synaptic transistors with charge-trapping perovskite quantum dots (PQDs) and atomic layer deposited (ALD) Al2O3 tunneling layers, which exhibit typical synaptic behaviors including excitatory postsynaptic current (EPSC), pair-pulse facilitation and dynamic filtering characteristics under both electrical or optical signal stimulation. Further, the combination of the high-quality Al2O3 tuning layer and highly photosensitive PQDs charge-trapping layer provides the devices with extensively tunable synaptic performance under optical and electrical co-modulation. Applying light during electrical modulation can significantly improve both the synaptic weight changes and the non-linearity of weight updates, while the memory effect under light modulation can be obviously adjusted by the gate voltage. The pattern learning and forgetting processes for “0” and “1” with different synaptic weights and memory times are further demonstrated in the device array. Overall, this work provides synaptic devices with tunable functions for building complex and robust artificial neural networks.

Near‐Infrared Organic Phototransistors with p‐Channel Photosensitive Layers of Conjugated Polymer Composed of bis‐Octyldodecyl‐Diketopyrrolopyrrole and Benzothiadiazole Units

AbstractA near‐infrared (NIR)‐absorbing conjugated polymer, poly[{2,5‐bis‐(2‐octyldodecyl)‐3,6‐bis‐(thien‐2‐yl)‐pyrrolo[3,4‐c]pyrrole‐1,4‐diyl}‐co‐{2,2′‐(2,1,3‐benzothiadiazole)‐5,5′‐diyl}] (PODTPPD‐BT), which is synthesized via a Stille coupling reaction, can play a dual role (charge transport and sensing) in NIR‐sensing organic phototransistors (OPTRs). The PODTPPD‐BT films, which feature two strong optical absorption peaks at wavelengths (λ) of 830 and 935 nm, possess a highly ordered crystalline state as evidenced by the synchrotron radiation grazing incidence X‐ray diffraction (GIXD) method. The OPTRs with the PODTPPD‐BT layers show typical p‐channel transistor behaviors in the dark, while their best dark performance is measured at a PODTPPD‐BT thickness (t) of 85 nm. The highest overall photocurrent is measured at t = 85 nm under illumination with three monochromatic NIR lights, while the highest photoresponsivity (RC) is obtained for the thickest PODTPPD‐BT layers (t = 145 nm). The flexible OPTRs with the PODTPPD‐BT layers demonstrate stable sensing characteristics upon optical on/off modulations using a high‐power NIR laser diode (λ = 905 nm) used for actual light detection and ranging (LiDAR) systems.

Colour-sensitive conjugated polymer inkjet-printed pixelated artificial retina model studied via a bio-hybrid photovoltaic device

In recent years, organic electronic materials have been shown to be a promising tool, even transplanted in vivo, for transducing light stimuli to non-functioning retinas. Here we developed a bio-hybrid optoelectronic device consisting of patterned organic polymer semiconductors interfaced with an electrolyte solution in a closed sandwich architecture in order to study the photo-response of photosensitive semiconducting layers or patterns in an environment imitating biological extracellular fluids. We demonstrate an artificial retina model composed of on an array of 42,100 pixels made of three different conjugated polymers via inkjet printing with 110 pixels/mm2 packing density. Photo-sensing through three-colour pixelation allows to resolve incoming light spectrally and spatially. The compact colour sensitive optoelectronic device represents an easy-to-handle photosensitive platform for the study of the photo response of artificial retina systems.

SYNTHESIS OF CHALCOPYRITE CuInSe2 (CIS) NANOSHEETS USING VITAMIN C AS AN ADJUVANT AND PHOTOELECTRIC PROPERTIES OF CIS THIN FILMS

To prepare chalcopyrite-phase CuInSe2 (CIS) nanosheets, green reductants were screened by using them to reduce the valence state of copper sources using a N,N-dimethylformamide/triethylene glycol(DMF/TEG) mixed solvent. CuCl was used as the copper source, indium chloride as the indium source, selenium powder as the selenium source, TEG as the anionic solvent, DMF as the cationic solvent, and Vitamin C (Vc) as the reductant. The influences of reaction temperature, reaction time, and Vc amount on the phase and composition of synthetic CuInSe2 nanosheets were examined, and the results were used to propose a reaction mechanism. The optional reaction conditions were a reaction temperature of 260 oC, a reaction time of 16 h, and a Vc amount of 0.20 g. Chalcopyrite-phase CIS nanosheets were synthesized with particle sizes of 14 µm and a uniform particle size distribution. CuInSe2 thin films displayed good surface smoothness and compactness in a 5.5 µm spin-cast film. The thin film showed a bandgap of 1.08 eV, a carrier concentration of 5.26×1016 cm-3 , and a carrier mobility of 150.41 cm2 V -1 S -1 . The results showed that this strategy can be used to prepare chalcopyrite-phase CIS which could be used as a photosensitive layer for various optoelectronic devices.

Influence of Ag@SiO2 with Different Shell Thickness on Photoelectric Properties of Hole-Conductor-Free Perovskite Solar Cells.

In this paper, Ag@SiO2 core-shell nanoparticles (NPs) with different shell thicknesses were prepared experimentally and introduced into the photosensitive layer of mesoscopic hole-conductor-free perovskite solar cells (PSCs) based on carbon counter electrodes. By combining simulation and experiments, the influences of different shell thickness Ag@SiO2 core-shell nanoparticles on the photoelectric properties of the PSCs were studied. The results show that, when the shell thickness of 0.1 wt% Ag@SiO2 core-shell nanoparticles is 5 nm, power conversion efficiency is improved from 13.13% to 15.25%, achieving a 16% enhancement. Through the measurement of the relevant parameters of the obtained perovskite film, we found that this gain not only comes from the increase in current density that scholars generally think, but also comes from the improvement of the film quality. Like current gain, this gain is related to the different shell thickness of Ag@SiO2 core-shell nanoparticles. Our research provides a new direction for studying the influence mechanism of Ag@SiO2 core-shell nanoparticles in perovskite solar cells.

Degradation behaviors of photoelectrical properties of mixed cation perovskite solar cells under equivalent 1 MeV electron irradiation

Perovskite solar cells have excellent photoelectric properties, but their physical mechanism of anti-irradiation is still incomplete. In this work, we investigate the photoelectrical properties of mixed cation perovskite solar cells by performing electron irradiation experiments, characterization measurements (i.e. photoluminescence spectra, UV–vis absorption spectra, and quantum efficiency spectra), and Monte Carlo simulation analysis. It is found that the electrical performance of solar cells degrades more severely with increasing electron irradiation fluence. Specifically, the open-circuit voltage independent of the electron irradiation is attributed to the stability of perovskite materials. The short-circuit current density (alternatively, photoelectric conversion efficiency) of irradiated solar cells decreases because two main reasons: the blackening of the glass substrate hampers the short-wavelength light to reach the photosensitive layer, and the Au electrode has a large number of recombination centers to shorten the carrier lifetime. It is suggested that the mixed cation perovskite solar cell has anti-electron irradiation performance by adopting the anti-irradiation glass and electrode.

Resonant and Sensing Performance of Volume Waveguide Structures Based on Polymer Nanomaterials.

Organic–inorganic photocurable nanocomposite materials are a topic of intensive research nowadays. The wide variety of materials and flexibility of their characteristics provide more freedom to design optical elements for light and neutron optics and holographic sensors. We propose a new strategy of nanocomposite application for fabricating resonant waveguide structures (RWS), whose working principle is based on optical waveguide resonance. Due to their resonant properties, RWS can be used as active tunable filters, refractive index (RI) sensors, near-field enhancers for spectroscopy, non-linear optics, etc. Our original photocurable organic–inorganic nanocomposite was used as a material for RWS. Unlike known waveguide structures with corrugated surfaces, we investigated the waveguide gratings with the volume modulation of the RI fabricated by a holographic method that enables large-size structures with high homogeneity. In order to produce thin photosensitive waveguide layers for their subsequent holographic structuring, a special compression method was developed. The resonant and sensing properties of new resonant structures were experimentally examined. The volume waveguide gratings demonstrate narrow resonant peaks with a bandwidth less than 0.012 nm. The Q-factor exceeds 50,000. The sensor based on waveguide volume grating provides detection of a minimal RI change of 1 × 10−4 RIU. Here we also present the new theoretical model that is used for analysis and design of developed RWS. Based on the proposed model, fairly simple analytical relationships between the parameters characterizing the sensor were obtained.

Importance of separating contacts from the photosensitive layer in heterojunction phototransistors

Abstract — We simulate the detection of light in solution-processed poly(3-hexylthiophene) (P3HT)-capped indium oxide (In 2 O 3 ) phototransistors with and without direct electrical contact between the P3HT and the source and drain contacts. Under illumination, the photogenerated carriers enhance the drain current of the transistor, enabling photodetection. We demonstrate improved phototransistor performance by eliminating direct electrical contact between the P3HT and the source and drain contacts due to the inhibition of hole current flow between the contacts in the off-state. The photoresponsivity and detectivity are improved by up to 2.5 and 7 orders of magnitude, respectively, and reach a maximum of 4.4 A/W and 8.7 × 10 17 Jones. Photodetection down to incident light powers as low as 5 pW/cm 2 is possible in the absence of direct contacts while detection is limited to 50 μW/cm 2 otherwise. We determine the photoresponse rise and fall time as 0.4 μs and 0.6 μs, respectively. Our study highlights the importance of using source/drain contacts that are separated from the photosensitive layer to realize optimal phototransistor performance. • Heterostructure phototransistor performance improved. • Off-state current reduced by 9 orders of magnitude. • Photodetectivity improved by 7 orders of magnitude. • Photodetection to powers as low as 5 pW/cm 2 .

High-performance self-powered perovskite photodetector for visible light communication

Real-time, accurate, and portable detection of wireless signal is a crucial part of mobile communication. A highly sensitive detector with quickly response is the indispensable component for obtaining optical signal. Organic/inorganic hybrid perovskite (CH3NH3PbI3) has been fabricated to photodetectors with a rapid response time and high responsivity by optimizing the quality of photosensitive layer with appropriate transport layer. The devices show high responsivity of 436 mA W−1 at 753 nm, fast response time of 1.7 μs, large linear dynamic range of 106 dB, as well as 75 kHz bandwidth, all under zero bias. Attributing to these prominent characteristics, this perovskite photodetector was integrated into an optical communication system, serving as a light sensor in receiver terminal. With it, the string, text and data files are transmitted by coded light successfully, accurately and rapidly. These results show the great potential of applications in visible light detection for organic/inorganic hybrid perovskite junction photodetectors.

Topological defects arrays and control of electro-convections in periodically photo-aligned bent-core nematics

The applicability of photo-alignment technique to bent-core nematics (BCN) is demonstrated in this paper. In order to cope with the inherent problems of BCN such as high working temperature and large working current, a photo-alignment technique, based on two superimposed photosensitive layers of azo and reactive mesogen, is used to produce symmetric and asymmetric planar alignments. With various surface conditions, defect lines arrays are self-assembled and ac-driven electro-convection (EC) rolls are modulated. Further inspections indicate that the defect lines arrays and EC rolls are in a competitive state, which reveal that the EC rolls in BCN belong to nonstandard EC scenarios. By producing defect lines and modulating EC rolls via photo-alignment technique, we could customize patterns in liquid crystals towards new photonic devices.

Ultraviolet filtration and defect passivation for efficient and photostable CsPbBr3 perovskite solar cells by interface engineering with ultraviolet absorber

The limited ultraviolet (UV) absorption of the common TiO2 electron-transporting layers (ETLs) and the trap states density as well as imperfect contact at TiO2/perovskite interface have been proposed as one of the main obstacles for realizing long-term photostability and high power conversion efficiency (PCE) of perovskite solar cells (PSCs). To address this issue,an advanced and universal interface engineering has been employed to block UV irradiation on perovskite films and to improve the interface contact with perovskite layer as well as decrease the trap states of TiO2 via chemical bonding by modifying an efficient UV absorber of2,2′-methylenebis (4-tert-octyl-6-benzotriazole phenol)(UV-360) on the TiO2ETLs. Additionally, the triazole groups in UV-360 combine with the uncoordinated cations of perovskite to reduce the defects at TiO2/perovskite interface, and a large-grained perovskite film with low grain boundaries is also formed on the UV-360 modified TiO2 ETLs owing to the reduction of perovskite nucleation sites. As a result, the modification of UV-360 on TiO2 greatly filtrates the UV attack on perovskite photosensitive layer and suppresses the interfacial charge recombination as well as promotes charge extraction. Finally, the carbon-based CsPbBr3 PSC tailored wtih UV-360 modified TiO2 ETLs free of encapsulation achieves a champion PCE up to 9.61% with super-stability under long-term light soaking as well as UV illumination, high temperature and high humidity conditions in air. Our work provides a new perspective to achieve PSCs wih high efficiency and stability by introducing UV-absorption functional materials.

Reorganization of a photosensitive carbo-benzene layer in a triptych nanocatalyst with enhancement of the photocatalytic hydrogen production from water

The preparation of a triptych nanomaterial made of TiO2 nanoparticles as semiconductor, Ag plasmonic nanoparticles and a carbo-benzene macrocyclic molecule as photosensitizer is described, and used to produce hydrogen by photo-reduction of pure deionized water under 2.2 bar argon pressure without any electrical input. Silver nanoparticles (~5 nm) are grafted onto the surface of commercial TiO2 nanoparticles (~23 nm) by a photo-deposition process using an original silver amidinate precursor. The thickness of the photosensitive layer (2 nm), which completes the assembly, plays a crucial role in the efficiency and robustness of the triptych nanocatalyst. Thanks to the organic layer reorganization during the first ~24 h of irradiation, it leads to an enhancement of the hydrogen production rate up to 5 times. The amount of silver and carbo-benzene are optimized, along with the mass concentration of nanocatalyst in water and the pH of the aqueous medium, to allow reaching a hydrogen production rate of 22.1 μmol·h−1·gphotocatalyst−1.

Smart pH-Regulated Switchable Nanoprobes for Photoelectrochemical Multiplex Detection of Antibiotic Resistance Genes.

Antibiotic resistance, encoded via particular genes, has become a major global health threat and substantial burden on healthcare. Hence, the facile, low-cost, and precise detection of antibiotic resistance genes (ARGs) is crucial in the realm of human health and safety, especially multiplex sensing assays. Here, a smart pH-regulated switchable photoelectrochemical (PEC) bioassay has been created for ultrasensitive detection of two typical subtypes of penicillin resistance genes bla-CTX-M-1 (target 1, labeled as TDNA1) and bla-TEM (target 2, labeled as TDNA2), whereby pH-responsive antimony tartrate (SbT) complex-grafted silica nanospheres are ingeniously adopted as signal DNA1 tags (labeled as SDNA1-SbT@SiO2NSs). The operations of the PEC bioassay depend on the switchable dissociation of the pH-responsive SDNA1-SbT@SiO2NSs complex under the external pH stimuli, thus initiating the pH-regulated release of ions pre-embedded in sandwich-type DNA nanoassemblies. At acidic conditions, the dissociation of SDNA1 tags (ON state) triggers the release of the embedded SbO+. Under alkaline conditions, the dissociation of SDNA1 tags is inhibited (OFF state). The detection of TDNA2 was achieved via DNA hybridization-triggered metal ion release. The unwinding of the introduced hairpin T-Hg2+-T fragment, hybridized with the second anchored signal DNA (SDNA2), ignites the release of Hg2+. The released SbO+ or Hg2+ ions would trigger the formation of Sb2S3/ZnS or HgS/ZnS heterostructure through ion-exchange with the photosensitive ZnS layer, giving rise to the amplified photocurrents and eventually realizing the ultrasensitive detection of penicillin resistance genes subtypes, bla-CTX-M-1 and bla-TEM. The as-fabricated pH-regulated PEC bioassay, smartly integrating the pH-responsive intelligent unit as SDNA tags, pH-regulated release of embedded ions, and the subsequent ion-exchange-based signal amplification strategy, exhibits high sensitivity, specificity, low-cost, and ease of use for multiplex detection of ARGs. It can be successfully used for measuring bla-CTX-M-1 and bla-TEM in real E. coli plasmids, demonstrating great promise for developing a new class of genetic point-of-care devices.

Silicon Nitride Deep-Ultraviolet Photoconductive Detector

In this letter, amorphous silicon nitride (Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> ) film grown by inductively coupled plasma chemical vapor deposition (ICPCVD) method is used as the photosensitive layer of deep ultraviolet (DUV) detection, whose thickness and roughness are 200 nm and 0.92 nm, respectively. The transverse symmetrical photoconductive detector with interdigital electrodes spacing of 4 μm is fabricated by photolithography, exhibiting ultrahigh photo-to-dark current ratio (PDCR) more than 105, fast fall speed of 127 ms and also a satisfying responsivity of 1.09 mA/W. This work lays a foundation for further researches on Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> in photonics and electronics.

Dependence of the Modulation Transfer Function on the Material and Design Parameters of HgCdTe IR FPAs

The calculation methods of the modulation transfer function (MTF) infrared (IR) focal plane arrays (FPAs) on the base of photodiodes are presented. The obtained results are based on the preliminary calculations of the areal distribution of quantum efficiency by modeling the 3-D diffusion process of photogenerated charge carriers in the photosensitive layer of IR FPA by the Monte Carlo method. The analysis of MTF is carried out for 1-D test patterns and 2-D “chess-type” test patterns, taking into account the basic photoelectric and design parameters of photosensitive elements.

Solar cell efficiency enhancement using a hemisphere texture containing metal nanostructures

One major problem of the conventional solar cells is low conversion efficiency. In this work, we have proposed a new design including hemisphere texturing on top and metallic plasmonic nanostructure under the silicon layer to enhance the optical absorption inside the photosensitive layer. The finite-difference time-domain (FDTD) method has been used to investigate the interaction of light with the proposed structure. The simulation results demonstrated that the designed structure gives rise to 40% light absorption enhancement and 27% solar cell efficiency enhancement compared to a simple cell structure. The hemisphere texturing acts as a light concentrator and results in local electric field enhancement inside the silicon layer, and metallic nanostructure excites the plasmons. By combining the advantages of these two designs, the short circuit of the proposed structure showed more than 65% enhancement compared to the conventional structure.

Towards high performance visible-blind narrowband near-infrared photodetectors with integrated perovskite light filter

Narrowband near-infrared (NIR) light detection is essential for optical imaging, machine vision, and spectroscopy. In this work, we demonstrate a strategy towards visible-blind narrowband NIR organic photodetectors by integrating perovskite thin film as the light filter. Lead phthalocyanine (PbPc):Fullerene (C60) bulk heterojunction which demonstrates high efficiency in photoexciton dissociation is used as the photosensitive layer due to excellent absorption of PbPc in NIR light region. Perovskite layer which has a strong absorption in the visible region but a weak absorption in the NIR region serves as a light filtering layer. More importantly, we have further improved the device performance by inserting copper phthalocyanine (CuPc) electron blocking layer between the ITO anode and PbPc:C60 bulk heterojunction. A high photoresponsivity (R) of 1.09 A/W, an external quantum efficiency (EQE) of 167%, and a narrow spectral response with the full width of half maximum of ~60 nm for NIR light of 808 nm wavelength is obtained.

Кинетика фотовосстановления меди(II) в композициях на основе ацетата меди и тетрафторпропианата меди

In the technology of manufacturing printed circuit boards by additive method, photoselective activation of dielectric materials is widely used. In order to obtain a given circuit pattern on the surface and in the holes of the printed circuit board it is necessary to form catalytically active centers for further chemical metallization. The aim of the work was to study the physical and chemical patterns of the photoactivation process of dielectric materials. Copper acetate (CuAc2) and copper tetrafluoropropyanate (Cu(TFP)2) having sufficiently high spectral sensitivity to UV radiation and good solubility in water were added to the analysed photosensitive compositions as copper-containing compounds (photopromotors). Chemical sensitizer in analysed photosensitive compositions is water-soluble organic compound – disodium salt of anthraquinone-2,6-disulfonic acid (Na2AS), acting as optical sensitizer in processes of photochemical reduction of copper(II). The process of photochemical reduction of copper(II) in the presence of sensitizers is possible with the presence of secondary reducing agents – alcohols. Such compounds are sorbitol and ethyl alcohol. In comparison with solutions, the study of the process of photo recovery of copper(II) in the dry layer of the photoactivator under the influence of ultraviolet radiation requires a special approach. A quantitative evaluation of the photochemical process was chosen to pass the photosensitive layer. On the transmission spectra of the photosensitive layer, it is clearly possible to distinguish a maximum at a wavelength of 520 nm, from the change of which during ultraviolet irradiation it is possible to judge the progress of photochemical transformation in the dry layer of photocomposition. The kinetics of the photochemical process were monitored by the transmission spectra of the 520 nm samples, which were taken immediately after irradiation. Survey of spectra was carried out on spectrophotometer of grade СF-18 in visible region of spectrum relative to chromatographic paper FN-5 without photoactivator. Mercury-quartz lamp of DRT-1000 grade was used as radiation source. Exhibiting carried out on GG-2258 installation in a special vacuum frame at distance 40 cm from a radiation source A phenomenological description is given of the process of photo-recovery of copper(II) in solid phase in compositions based on copper acetate and copper tetrafluoropropionate in form of kinetic equations. Fractional partial reaction orders by components of the photocomposition indicate the complexity of the process in the systems studied. It has been found that, depending on the kind of copper-containing compound, the process of copper photo-recovery is described by different kinetic equations, suggesting a different mechanism of copper(II) photo-recovery. It has been shown that complicating the composition of the photosensitive composition results in a slight change in the reaction order of the main components. The description of the kinetics of the photochemical process by means of mathematical equations will allow to determine in advance the time by which the specified degree of conversion of the substance will be achieved.