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4,4-Difluoro-4-bora-3a,4a-diaza-sindacene (BODIPY) is a sort of photofunctional dye which possesses advantages including strong light-capturing property, high photon-resistance, etc. Meso-N substituted aza-BODIPY is a crucial derivative of BODIPY scaffold that has the favorable optical properties and a significant spectral redshift. The photophysical properties can be tuned by molecular design, and the attenuation path of the excited state energy release of absorbed light energy can be well controlled via structural modifications, enabling tailored application. It has been extensively employed in life medicine fields including fluorescence imaging diagnosis, photodynamic therapy photosensitizer and photothermal therapy reagent and so forth. Extensive research and review have been performed in these areas. However, BODIPYs/aza-BODIPYs have a significant role in energy, catalysis, optoelectronics, photo-responsive materials and other fields. Nevertheless, there are relatively few studies and reviews in these fields on the modification and application based on BODIPY/aza-BODIPY scaffold. Herein, in this review we summarized the application of BODIPY/aza-BODIPY in the aforementioned fields, with the molecular regulation of dye as the foundation and the utilization in the above fields as the objective, in the intention of providing inspiration for the exploration of innovative BODIPY/aza-BODIPY research in the field of light resource conversion and functional materials.

In wireless communication and radar systems, long-distance signal transmission poses significant challenges that affect overall system performance. In this paper, we propose an innovative bistatic radar cross section (RCS) testing system designed to address these challenges, with a particular focus on its long-distance signal transmission capabilities. This system is capable of accurately measuring the RCS of a target and improving multipath channel modeling accuracy by using precise RCS values. The integrated upper computer software extracts amplitude and phase information from received echo signals, processes these data, and provides detailed outputs including the target’s RCS, one-dimensional image, and two-dimensional image. The experimental results obtained prove that this system can not only achieve effective long-distance signal transmission but also substantially enhance the accuracy of RCS measurements, offering reliable support for multipath channel modeling. However, the conclusions drawn are preliminary and require further experimental validation to fully substantiate this system’s performance. Future work will focus on improving system accuracy, minimizing the impact of environmental noise, and optimizing data-processing methods to enhance the efficiency of wireless communication and radar applications.

Graphene and related two-dimensional materials have attracted great research interests due to prominently optical and electrical properties and flexibility in integration with versatile photonic structures. Here, we report an in-fiber photoelectric device by wrapping a few-layer graphene and bonding a pair of electrodes onto a tilted fiber Bragg grating (TFBG) for photoelectric and electric-induced thermo-optic conversions. The transmitted spectrum from this device consists of a dense comb of narrowband resonances that provides an observable window to sense the photocurrent and the electrical injection in the graphene layer. The device has a wavelength-sensitive photoresponse with responsivity up to 11.4 A/W, allowing the spectrum analysis by real-time monitoring of photocurrent evolution. Based on the thermal-optic effect of electrical injection, the graphene layer is energized to produce a global red-shift of the transmission spectrum of the TFBG, with a high sensitivity approaching 2.167×104 nm/A2. The in-fiber photoelectric device, therefore as a powerful tool, could be widely available as off-the-shelf product for photodetection, spectrometer and current sensor.

The manufacturing of flutes has always relied on traditional ceramics and metals, which may be affected by various factors during the manufacturing process, as well as the lack of intelligent sensing functions, resulting in poor sound quality and performance of the instrument. The purpose of this article is to explore the use of the intelligent sensing function of conjugated materials to create intelligent flute training equipment, achieve automatic tuning, volume control, etc., and improve the playing experience and training effect of the instrument. This article first analyzes the smart sensing function of conjugate materials and applies it to smart flute training equipment; then, introduces photosensitive materials at appropriate locations to change the size and shape of the flute’s sound hole, thereby adjusting the timbre; finally, uses smart flute training based on conjugate materials for real-time perception of performers’ performance experiments. The test results show that the average delay time of the conjugate material trench is reduced by 73.1% compared with the average delay time of the ceramic trench, and is reduced by 63.5% compared with the average delay time of the metal trench. This shows that the conjugated material flute is more intelligent and can quickly respond to the player’s performance and automatically control and respond.

Abstract Parameter estimation for solar photovoltaic (PV) models is a challenging issue due to the complex nonlinear multivariable of the current‐voltage and power‐voltage characteristics. In this article, an improved heap‐based algorithm (IHBA) is proposed to improve the performance of a recently published algorithm called heap‐based algorithm (HBA). The HBA's performance is enhanced by applying an effective exploitation feature to boost the searching around the leader position with the goal of enhancing its global search capabilities and avoiding becoming trapped in a local optimum. The proposed IHBA and the standard HBA are developed considering the practical limits of the electrical parameters of PV models to minimize the root mean square error (RMSE) between the experimental and simulated results. The numerical analyses for the PVM‐752GaAs PV module including single‐diode model (SDM), double‐diode model (DDM) and triple‐diode model (TDM) are investigated to estimate five, seven, and nine electrical parameters of these models, respectively. Besides, different recent optimization techniques are simulated with fair comparisons, which are forensic‐based investigation (FBI), equilibrium optimizer (EO), Jellyfish Search (JFS), HBA, Marine Predator Algorithm (MPA) and Enhanced MPA (EMPA), and are compared with the proposed IHBA. Several separate runs are illustrated for the proposed IHBA in comparison with others, whereas the whisker box plot and T‐tests are activated to evaluate their effectiveness metrics. The simulation results derive higher superiority of the proposed IHBA with the minimum RMSE objective and standard deviation of (0.000228 and 3.7 × 106), (0.000184 and 1.93 × 105) and (0.000017 and 2.11 × 105) for SDM, DDM, and TDM, respectively, with respect to the standard HBA, other recent and reported optimization techniques. Additionally, the P‐indicator is applied in this study to illustrate the evidence for the alternative hypothesis. Small values of the P‐indicator for the proposed IHBA are obtained compared to the standard HBA and other recent optimization techniques, where IHBA achieves p‐value of 1.0336 × 1017, 4.037 7× 1011 and 2.1490 × 1010 for SDM, DDM and TDM, respectively. The H‐value is always one which elucidates that the hypothesis probability is not more than 5% for all algorithms for SDM, DDM and TDM. Moreover, the proposed IHBA demonstrates higher efficiency as it provides the first ranks in the confidence interval values compared with other algorithms. Furthermore, the proposed IHBA is significantly employed for the SQ_150 PV module considering the TDM with diverse solar irradiance and temperatures, where significant closeness between the emulated and experimental P–V curves is evidently demonstrated.

Abstract This paper presents a new hybrid successive discretisation algorithm, used to calculate the parameters of the photovoltaic cells and panels, by the one diode model and the two diode model. Nine known datasets from the specialised literature were used to validate the new algorithm and then it was firstly applied for two new datasets. For the first time only one algorithm is applied to extract the parameters, in both cases—one and two diode models. The new datasets are for commercial monocrystalline silicon and amorphous silicon photovoltaic cells. The main test used to prove the performance of HDSA is the root mean square error. Other four tests were used for comparison: the mean absolute error, the mean bias error, t‐statistic, and the coefficient of determination. The hybrid successive discretisation algorithm proved its accuracy and reliability for parameter extraction of different types of photovoltaic cells and panels for all datasets used. Comparing the hybrid successive discretisation algorithm with the best algorithms from the specialised literature shows an improvement of the root mean square error by up to10.4% for the one diode model and by up to 7.5% for the two diode model, respectively.

Abstract The present study introduces an analytical approach for predicting net power for high‐concentrating photovoltaic systems (HCPV). Wind speed, surface radiation, and size of the backplate, which acts as a heat spreader, were found to be of high impact in increasing solar cell efficiency and maximum produced power. The efficiency increased by 5% as the wind shifted from light air (0.5 m/s) to fresh breeze (10 m/s). Also, it increased by 1.64% as the aluminium backplate shifted from a shiny (ɛ = 0) to a dark (ɛ = 1) surface. Furthermore, increasing heat‐spreader length or wind velocity caused a logarithmic increase in solar cell efficiency. On the other hand, both parameters caused an exponential increase in consumed power due to the operation of a tracking system. Thus, optimal values of heat‐spreader length at which maximum net power is produced exist. A case study based on the annual average values of the hourly‐basis meteorological data for the period 2015 to 2018 for two cities in Saudi Arabia was conducted. It was found that the size of the heat spreader could be reduced by 36% for concentration ratio up to 2000 while concurrently increasing the net power by 2.6% and 6% for the systems built in Riyadh and Dammam, respectively.

Abstract The photovoltaic (PV) cells are highly sensitive to temperature variations. The linear variation of PV cells with operating temperature could lead to the loss of conversion efficiency and permanent damage of PV material. To address this critical issue, while improving the performance of solar photovoltaic system (SPVS) during the operating period, the deployment of a proper cooling system is a prime requisite in the design process. Considering this, two new and cost‐effective cooling techniques are proposed in this study, which can improve efficiency and increase the life of the PV panel. The first technique is the active cooling design with water. The proposed design enhances the access to PV cells to maximize cooling. The second one is an improved passive cooling technique that uses fins mounted on the backside of PV module. This further reduces the temperature by increasing the heat dissipation. Additionally, a third PV module without any cooling system is deployed as a reference margin. The techniques have been experimentally evaluated and a recommendation is made in order to reduce the temperature variation across the PV panel.

Abstract The increased energy demand with recent advancement in technology has led the global energy producers to move towards solar energy. Partial shading is a phenomenon that can severely affect the production of the solar power in the photovoltaic system. With partial shading situation, the cascaded solar panels show numerous dummy peaks both in power–voltage (P–V) and current–voltage (I–V) curves, resulting in difficulty of extracting maximum power. A dummy peak elimination based MPPT technique is introduced in proposed work for accurate tracking of maximum power. The proposed dummy peak elimination based MPPT estimates the dummy peaks without imposing any high computational burden for the processor. The proposed technique has better dynamic response and is more compatible for real time application compared to existing optimization‐based techniques. The proposed dummy peak elimination based MPPT is tested on a practical system with 3S configuration having three 249 W PV panels for different shading patterns, which displays acceptable outputs with good dynamic performance and better efficiency.

Abstract As a clean and renewable energy source, solar energy is a competitive alternative to replace conventional fossil fuels. Nevertheless, its serious fluctuating nature usually leads to a poor alignment with the actual energy demand. To solve this problem, the direct solar‐to‐electrochemical energy conversion and storage have been regarded as a feasible strategy. In this context, the development of high‐performance integrated devices based on solar energy conversion parts (i.e., solar cells or photoelectrodes) and electrochemical energy storage units (i.e., rechargeable batteries or supercapacitors [SCs]) has become increasingly necessary and urgent, in which carbon and carbon‐based functional materials play a fundamental role in determining their energy conversion/storage performances. Herein, we summarize the latest progress on these integrated devices for solar electricity energy conversion and storage, with special emphasis on the critical role of carbon‐based functional materials. First, principles of integrated devices are introduced, especially roles of carbon‐based materials in these hybrid energy devices. Then, two major types of important integrated devices, including photovoltaic and photoelectrochemical‐rechargeable batteries or SCs, are discussed in detail. Finally, key challenges and opportunities in the future development are also discussed. By this review, we hope to pave an avenue toward the development of stable and efficient devices for solar energy conversion and storage.

Abstract Photovoltaic emulators are a specific type of power electronics system to mimic the behaviour of a photovoltaic (PV) panel or array and facilitate the testing of energy systems. Existing solutions usually require sophisticated hardware design and fast computing. This paper presents a simple, reliable, and effective circuit‐based photovoltaic (PV) emulator based on the equivalent PV stacked cells. The PV emulator can be used for solar system testing and analysis, such as maximum power point tracking (MPPT) and partial shading effect. The I–V and P–V characteristic curves of the emulator have been generated by using an LTspice simulator. It is experimentally investigated and compared with a real PV panel and existing emulator products. The experiment results show good agreement with the mimicked actual PV panel. The proposed PV emulator shows a better dynamic response and shorter settling time than several benchmarked commercial products. The enhancement in the time response is due to the simplicity of the emulator, where a few power diodes and some resisters are used. In addition to simplicity, the PV emulator is very cost‐effective.

Abstract Solar panels around the globe are primarily designed as a plug‐and‐play solution and the end users are not allowed to repair the panel in case of damage. Natural loadings such wind, snow, sand and hail can lead to irreparable damage to the solar panels and the easiest solution to fix the damaged solar panel is to replace it. This design philosophy leads to a huge quantity of electronic waste as it completely ignores the repairability of the solar panels. In this regard, the presented research work details the development and testing of modular solar panel with performance similar to the traditional design. The modular design was tested for power transfer, re‐connection upon impact and the ability to replace the selected parts in case of permanent damage without the need of replacing the entire solar panel. This experimental research work delivers a modular solar panel design that has ease of repairability in case of damage. Furthermore, a detailed economic analysis has been provided for several real‐world scenarios that indicate its suitability over existing commercially available solutions.

Abstract The maximum power generation in the solar photovoltaic (PV) array is reduced due to the abnormal conditions such as module mismatch, string faults and damage of the PV modules, which reduces the efficiency and reliability of the system. Conventional protection devices fail to detect the faults, which leads to protection issues and fire threats in the PV plants. This paper proposes a new fault detection algorithm to identify the faults in the PV array and the PV string. A simple analysis is developed for fault detection under different fault conditions, such as line–line (L‐L) fault, line–ground (L‐G) fault and short‐circuit fault with multiple strings, and the values of their current indicator and threshold are predetermined. Based on these values, the proposed fault detection algorithm identifies the fault in the PV array and the PV string, with a reduced number of current sensing devices. The effectiveness of the proposed algorithm is tested and verified through MATLAB simulation and experimentation under various operating conditions of the solar PV plant.

Abstract In this work, a new method for obtaining the current–voltage curve for crystalline silicon and thin‐film flat panels is presented. It is based on the single‐diode model, with a variable shunt resistance and series resistance. New expressions for the shunt resistance and open circuit voltage as a function of the temperature and irradiance are deduced. Besides, a procedure to translate the series resistance to arbitrary conditions is proposed. The diode ideality factor and shunt resistance are obtained by optimization. The rest of the parameters that appear in the current–voltage curve are obtained from the module measurements by means of theoretical expressions. The procedure for obtaining the current–voltage curve under arbitrary operating conditions is also described. The results obtained with the developed model are compared with experimental measurements in cadmium telluride and amorphous silicon modules, and with results published in the literature for other technologies. The model faithfully reproduces the experimental values. For all the modules, the root mean square error for the maximum power is lower than 2% (below 1.5% in most cases). These errors are lower than those reported in the literature for other models. In particular, the results are significantly more exact in the case of thin‐film modules.

Abstract An effective and efficient photovoltaic performance is significantly affected by the interface between different constituents of dye sensitized solar cells (DSSC). A novel dual post treatment of TiCl4 and urea solutions on different layers of TiO2 electrode is addressed and the TiO2 particle morphology, dye‐adsorption amount on the TiO2 electrode and the photovoltaic performance of the DSSC based on those electrodes are characterised in this work. TiCl4 treatment can form more binding site on TiO2 particles and urea treatment structures a thin layer of g‐C3N4 on the surface of TiO2 particles. This strategy can not only effectively increase the dye‐adsorption for light‐harvesting, but also facilitate the electron transfer through inhibiting the charge recombination between TiO2 and electrolyte, and moreover, it provides excess electrons for the photoanodes. The DSSC fabricated from TiO2 electrode processed with urea treatment on the sixth layer exhibited the highest power conversion efficiency of 8.94% with a short current density Jsc of 24.09 mA cm–2, an open circuit voltage Voc of 583 mV and a fill factor of 63.8.

Abstract Optical wireless power transmission (OWPT) systems are attractive photonic systems based on light sources and solar cells. To improve the visual design of practical consumer applications, we applied visible colour filters to change the normal black appearance of solar cells. Different colours made by multilayer‐type filters on solar cells were investigated for control of visible colour with maintained power transmission efficiency. The surface colours seen by the eyes and standard cameras were controlled by the filter as expected from the filter spectral response. The electrical output characteristics of the solar cell covered with the filter were experimentally measured in order to confirm the OWPT performance. The results showed that the OWPT system can change colour appearance with an acceptable slight deterioration of performance.

Abstract This work aims at developing and validating mathematical models and empirically evaluating a water‐film cooling system for commercial photovoltaic modules. Methodologically, thermal, electrical and climatological data measured in a specific purpose on‐grid outdoor test unit were used. In this work they are used to study the improvement in the performance of photovoltaic energy production due to temperature reduction. The first‐order state‐space linear parametric model presents the best performance to predict the temperature of the uncooled photovoltaic modules, with normalised mean square error (NRMSE) of 86.75%. In contrast, the non‐linear model performance of cooled photovoltaic modules is lower, with NRMSE of 44.5%; however, the results show that the performance of the complete thermoelectric model is satisfactory, with NRMSE of 76.38%. On the other hand, empirical tests showed that the cooling system reduces temperature in 15–19%, on average, and to a maximum of 35%. In terms of power, there are average gains of 5–9%, and maximum gains of 12%. Regarding gross generation, there are average gains of 2.3–6%, and maximum gains of 12%. It was concluded that it is possible to mathematically model and predict this generation using non‐linear models with a 0.2% error between modelled and measured generation.

Dielectric metamaterials with high refractive indices may have an incredible capability to manipulate the phase, amplitude, and polarization of the incident light. Combining the high refractive index and the excellent electrical characteristics of the hybrid organic-inorganic perovskites (HOIPs), for the first time we experimentally demonstrate that metamaterial made of HOIPs can trap visible light and realize effective photon-to-electron conversion. The HOIP metamaterials are fabricated by focused ion beam milling on a solution-grown single-crystalline HOIP film. The optical absorption is significantly enhanced at the visible regime compared to that of the flat HOIP film, which originates from the excited Mie resonances and transverse cavity modes with inhibited interface reflection. Furthermore, compared to the flat film, the HOIP metamaterial shows increased photocurrent of up to ~40%, where the effective photocarrier generation efficiency increases by ~40% and the related internal efficiency by ~20%. Our data point to the potential application of HOIP metamaterials for high-efficiency light trapping and photon-to-electron conversion.

A tri-state optical signal detector (TOD) is designed in this article to improve the accuracy and stability of decoding results of the ternary optical computer (TOC). The TOD consists of three modules: a light-sensing module, a voltage divider module, and a data latching and conversion module. First, a voltage divider circuit with adjustable resistors is used to achieve parallel optical–electrical signal conversion for each LCD pixel on a photosensitive sensor plus a latch structure. Second, the problem of the parallel storage of data after photoelectric conversion is solved. Third, a transcoding circuit from the output signal of the TOD to the input signal of the tri-state optical encoder (TOE) is given. The experimental results show that the tri-state optical signal detector designed in this paper is effective and feasible.

Covalent carbon nitrides (CNs) have been widely used in photocatalysis and energy storage for their graphitic 2D structure and semiconducting properties. However, carbon nitrides, normally with a bandgap of 2.7 eV, can absorb only the ultraviolet and blue fraction of solar spectrum (λ

According to the solar-blind characteristic of the pantograph arc spectrum distribution, an arc detection method based on the photoelectric conversion mechanism for urban rail was proposed, and the design of each part of the arcing detection system was completed. Through the analysis of arc spectral distribution, the 275-285 nm band was determined as the detection characteristic waveband. The optical acquisition system located on the roof of the train collects the arc characteristic light and transmits it to the photoelectric conversion module, which converts the received optical signal into the corresponding current signal linearly. After amplification, comparison and screening in this module, the optical signal is sent to the data processing module for output display. Finally, a field test conducted on an urban rail transit line shows that this arc detection system can effectively detect the pantograph arc phenomenon and reflect the arc intensity linearly avoiding the influence from natural light, train load and train running direction.

This paper reports a novel design of an artificial pigment-protein complex, created by supramolecular binding of chlorophyll a (Chl a) in the hydrophobic cavity of single-ring mutant of bacterial GroEL (SR). The results show that Chl a molecules assembled in SR nano-ring retain their native structure, and an increase of loading amount (up to ~26 pigment molecules per protein nano-ring) with the equilibrium concentration of Chl a upon dialysis has been observed. It is further seen that the nanoscale organization of Chl a in SR leads to a significant quenching of Chl a fluorescence, especially at high loadings. Moreover, the photostability of Chl a encapsulated in SR is significantly enhanced in comparison with free Chl a, as evidenced by an up to 6-fold increase of its half-life time. Both the interaction of Chl a with SR and the interaction between Chl a molecules contribute to photostability. Finally, it is shown that the Chl a-SR complex has good photoreduction activity as well as photoelectrochemical activity under visible light illumination. The maximum photoelectric conversion efficiency of the Chl a-SR-sensitized solar cells is around 1.09%. The strategy presented herein is believed to be instrumental in the design of effective photoenergy conversion materials.

Strong ambient light and the resultant photoelectric conversion saturation of an avalanche photo diode (APD) may signficantly deteriorate the received signal in visible light communication (VLC) systems. Hence, in this paper we characterize the signal received from an APD under strong ambient light based on our experimental data. To illustrate the phenomenon of APD saturation, we investigate the transmission rate and analyze the link budget. In order to achieve dimming control, we then conceive a unary-coded VLC system for maintaining the user-defined dimming level. We calculate both the upper and lower bounds of the achievable transmission rate of the unary-coded VLC system.

Bioelectronics, an emerging discipline formed by the biology and electronic information disciplines, has maintained a state of rapid development since its birth. Amongst the various functional bioelectronics materials, bacteriorhodopsin (bR), with its directional proton pump function and favorable structural stability properties, has drawn wide attention. The main contents of the paper are as follows: Inspired by the capacitive properties of natural protoplast cell membranes, a new bio-capacitor based on bR and artificial nanochannels was constructed. As a point of innovation, microfluidic chips were integrated into our device as an ion transport channel, which made the bio-capacitor more stable. Meanwhile, a single nanopore structure was integrated to improve the accuracy of the device structure. Experiments observed that the size of the nanopore affected the ion transmission rate. Consequently, by making the single nanopore’s size change, the photocurrent duration time (PDT) of bR was effectively regulated. By using this specific phenomenon, the original transient photocurrent was successfully transformed into a square-like wave.

The photoelectric performance of quantum dots (QDs)-based nanocomposites is closely related to the optical properties of QDs, which play a critical role in the optical absorption and separation/transfer of charge carriers. Herein, we report a nanocomposite composed of light absorber PbS1−xSex quantum dots (QDs), electron-conducting multiwalled carbon nanotubes (MWCNTs) and hole-conducting poly-3-hexylthiophene (P3HT) with tunable photoelectric conversion performance. In addition to using the quantization effect, we proposed solid-solution PbS1−xSex QDs (x = 0, 0.25, 0.5, 0.75, 1) for band gap engineering. In particular, we successfully synthesized relatively small (~5.3 nm) and uniform QDs via the hot-injection method by using PbCl2, S/Se powder and environmentally friendly oleylamine (OLA) as the precursors and/or solvent. By increasing the content of Se, the band gap of PbS1−xSex QDs decreased along with the decrease in the conduction band and valence band edges. The suitable energy level alignment enabled the efficient transfer of photoinduced charge carriers, and hence a much higher photoelectric conversion performance of the PbS1−xSex-QD@MWCNT/P3HT nanocomposites than the individual QDs, P3HT, and binary PbS1−xSex-QD@MWCNT, as well as the best performance, was achieved over PbS0.75Se0.25-QD@MWCNT/P3HT.

Abstract Materials for simultaneous photoelectric and thermo‐electric dual conversions and modulations, where photon can modulate the thermoelectric conversion, and temperature can modulate the photoelectric conversion, may find potential applications where light (including a laser) can remotely turn on, turn off, or modulate a thermoelectric generator, a cooler, or a temperature sensor, and vice versa, temperature (heating/cooling) can turn on, turn off, or modulate a photoelectric device such as a photo detector or a solar cell. Here, it is demonstrated that such simultaneous dual conversion or modulation can be achieved via a ternary composite, e.g., a poly‐3‐hexyl‐thiophene thin‐film doped with both phenyl‐C61‐butyric acid methyl ester and iodine. This finding may result in the development of lightweight, flexible shape, cost‐effective, renewable, environmentally friendly, biocompatible, and scalable materials, devices, and systems for clean energy harvestings (such as solar and waste heat dual energy harvesting) as well as light/heat dual‐sensing sensors, modulators, and controllers.

To develop donor–acceptor–donor (D–A–D) type new photo-electric conversion materials, new tetrathiafulvalene (TTF)-Mq2-TTF complexes 1 and 2 were synthesized, where two bis(n-hexylthio)tetrathiafulvalene moieties were attached to the Mq2 part (1: M = Zn, 2: M = Ni, q = 8-quinolinato) through amide bonds. UV-Vis absorption spectra of these complexes showed strong and sharp absorption maxima at 268 nm and small absorption maxima around 410 nm, corresponding to those of Znq2 and Niq2 parts. Furthermore, complexes 1 and 2 exhibited absorption tails up to a much longer wavelength region of ca. 700 nm, suggesting the appearance of charge transfer absorption from TTF to the Mq2 parts. The photoelectrochemical measurements on the thin films of these complexes casted on ITO-coated glass substrates suggest that positive photocurrents can be generated by the photoinduced intramolecular electron transfer process between the TTF and Mq2 parts.

The high-power high-bandwidth photodetector is required at the base station in the Radio over Fiber（ROF）system.This paper presents a power combining circuit research on PI type photoelectric detector array.The probe is embedded in an inductor connected with artificial transmission lines.In order to obtain high power and large bandwidth signal,each group of unit structure of PI type circuit of photoelectric detector are connected with inductors based on the structure of array structure together to constitute the required structure.In order to achieve the best match,the first and final stage synthetic circuit branches are cascaded with two photodiode to reduce the equivalent capacity of synthetic circuit.Simulation results show that this arrangement can effectively combine multiple RF photocurrents while keeping the large bandwidth.Comparing with traveling wave detector array at the same level,the combining performance of PI type photoelectric detector array is better.

This paper provides an overview of recent studies on energy storage in bifunctional TiO2 composite materials under UV and visible light. The working mechanism, property improvements and applications of these bifunctional TiO2 composite systems are introduced, respectively. The latest results obtained in our laboratory, especially a new process for photoelectric conversion and energy storage in TiO2/Cu2O bilayer films under visible light, are also presented. Hopefully this review will stimulate more fundamental and applied research on this subject in the future.

Four nanostructured Au electrodes were prepared by a simple and templateless electrochemical deposition technique. After complexing with a biotinylated polythiophene derivative (PTBL), photocurrent generation and performance of PTBL/Au-nanostructured electrodes as photoelectrochemical biosensors were investigated. Among these four nanostructured Au electrodes, vertically oriented nanobranches on the electrode significantly improved the photoelectric conversion, because the vertically oriented nanostructures not only benefit light harvesting but also the transfer of the photogenerated charge carriers. Owing to this advantaged nanostructure, the PTBL/Au-nanobranch electrode showed higher sensitivity and faster response times in the photoelectrochemical detection of a streptavidin-biotin affinity reaction compared to a PTBL/Au-nanoparticle electrode.

Based on the demands of Confocal Auto-Focus system, the implementation method of signal measurement circuit and control circuit is given. Using the high performance instrumental amplifier AD620BN, low noise precision FET Op amplifier AD795JRZ and ultralow offset voltage Op amplifier OP07EP, a signal measurement circuit used to converse the two differential light intensity signal to electric signal is designed. And a control circuit which takes MCU MSP430F149 as core processes the former signal and generate a control signal driving the platform for auto-focusing. The experimental results proved the feasibility and correctness of circuits. And the system meets the design requirement.

In this article we have investigated two important properties of metallic nano-resonators which can substantially improve the temperature performances of infrared quantum detectors. The first is the antenna effect that increases the effective surface of photon collection and the second is the subwavelength metallic confinement that compresses radiation into very small volumes of interaction. To quantify our analysis we have defined and discussed two figures of merit, the collection area A _coll and the focusing factor F. Both quantities depend solely on the geometrical parameters of the structure and can be applied to improve the performance of any detector active region. In the last part, we describe three-dimensional electronic nano-resonators that provide highly subwavelength confinement of the electromagnetic energy, beyond the microcavity limits and illustrate that these device architectures have a tremendous potential to increase the temperature of operation of infrared quantum detectors.