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The development and utilization of perovskites are beneficial to improve or even change the optical properties of devices and obtain fascinating performances such as higher photoelectric conversion efficiency, better thermal stability, higher external quantum efficiency, more excellent remodeling, and flexibility. So, there are many articles on perovskite reviews having been reported from synthesis, properties to various applications (such as optoelectronic devices, electrical memristor, etc.). Based on the reported review of perovskites, this study will make a further supplement to the research progress of perovskites in visible light communication (VLC), optical neuromorphic devices, and highlight huge development prospects in these emerging fields in recent years. First, we briefly reviewed the preparation methods of common perovskite materials, followed by the optical and electrical characteristics. Then, the specific applications of optical properties based on perovskite materials are emphatically investigated, in addition to traditional photovoltaic devices, especially the latest cutting-edge fields of information encryption and decryption, VLC as well as optical memristive devices for photonic synapse and photonic neuromorphic computing. Finally, the main conclusions and prospects are given. Perovskite-based optical memristive devices are enabled to assist photonic neuromorphic calculations, showing huge potential application prospects in intelligent integrated chip fusing sensing, storage, and computing.

The oxidation step in Oolong tea processing significantly influences its final flavor and aroma. In this study, a gas sensors detection system based on 13 metal oxide semiconductors with strong stability and sensitivity to the aroma during the Oolong tea oxidation production is proposed. The gas sensors detection system consists of a gas path, a signal acquisition module, and a signal processing module. The characteristic response signals of the sensor exhibit rapid release of volatile organic compounds (VOCs) such as aldehydes, alcohols, and olefins during oxidative production. Furthermore, principal component analysis (PCA) is used to extract the features of the collected signals. Then, three classical recognition models and two convolutional neural network (CNN) deep learning models were established, including linear discriminant analysis (LDA), k-nearest neighbors (KNN), back-propagation neural network (BP-ANN), LeNet5, and AlexNet. The results indicate that the BP-ANN model achieved optimal recognition performance with a 3–4–1 topology at pc = 3 with accuracy rates for the calibration and prediction of 94.16% and 94.11%, respectively. Therefore, the proposed gas sensors detection system can effectively differentiate between the distinct stages of the Oolong tea oxidation process. This work can improve the stability of Oolong tea products and facilitate the automation of the oxidation process. The detection system is capable of long-term online real-time monitoring of the processing process. [ABSTRACT FROM AUTHOR]

The application of heterogeneous catalysts in dimethyl carbonate (DMC) synthesis from methanol is hindered by low activation efficiency of methanol to methoxy intermediates (CH3O*), which is the key intermediate for DMC generation. Herein, a catalyst of alkali metal K anchored on the CuO/ZnO oxide is rationally designed for offering Lewis acid–base pairs as dual active centers to improve the activation efficiency of methanol. Characterizations of CO2‐TPD, NH3‐TPD, XPS, and DRIFTS revealed that the addition of Lewis base K observably boosted the dissociation of methanol and combined with Lewis acid CuO/ZnO oxide to adsorb the formed CH3O* stably, thus synergistically promoted the transesterification. Finally, the CuO/ZnO‐9%K2O catalyst exhibited the optimal catalytic activity, achieving a high yield of 74.4% with an excellent selectivity of 98.9% for DMC at a low temperature of 90°C. The strategy of constructing Lewis acid–base pairs provides a reference for the design of heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

Thermocatalytic conversion of redundant CO2 to useful methanol is an attractive route to address both energy and environmental crises simultaneously. However, existing copper/oxide catalysts widely used in these thermocatalytic processes still suffer from low methanol yield under mild reaction conditions. In this work, we design inverse oxide/Cu catalysts to achieve superior thermal catalytic performance for CO2 hydrogenation. The optimized ZnO/Cu-1.0 catalyst exhibits maximum CH3OH selectivity of 83.4% and space–time yield (STY) of 170.9 g CH 3 OH kg cat - 1 h - 1 in CO2 hydrogenation at 210 °C, nearly twofold higher STY than the previous optimal inverse ZnO/Cu catalysts ( 89.6 g CH 3 OH kg cat - 1 h - 1 at 250 °C). Importantly, ZnO/Cu-1.0 catalyst displayed not only a satisfactory catalytic stability but also a superior CH3OH STY with a time-on-stream of 24 h. Such inverse configuration of catalysts will pave the way for new strategies to design high-performance thermocatalytic catalysts and promote their commercialization. Typical inverse ZnO/Cu-1.0 catalysts have been demonstrated and achieved to significantly facilitate the activation of inert CO2 molecules to produce methanol, due to its special physicochemical properties and strong ZnO–Cu interaction [ABSTRACT FROM AUTHOR]

The development of vision bionic systems is indispensable for the perception, memory, and processing of optical signals, which promotes the exploration of efficient visual perception systems. In this work, a simple and novel two‐terminal optoelectronic memristor based on the CuAlAgCr/TiO2/W (CTW) structure is prepared, where the CuAlAgCr high‐entropy alloys are employed as the top electrode for the first time. Before annealing, the CTW optoelectronic memristor exhibited fascinating performance, including uniformly distributed operating voltage, reliable data retention, and a higher switching ratio. Moreover, the optoelectronic memristor can be reversibly switched between volatile and nonvolatile memories by adjusting compliance currents. The CTW optoelectronic memristor annealed in air exhibits various artificial synaptic functions, such as short‐term memory, optical learning, and forgetting behavior under the illumination of the laser. The photo‐response current is increased from nano‐ampere to micro‐ampere level. Furthermore, a logic function unit based on CTW optoelectronic memristor is proposed, which realizes "AND" operation. Furthermore, first‐principles calculations of the CTW structure are performed to describe the influence of photocarriers on the barrier height at the CuAlAgCr‐TiO2 interface, revealing the working mechanism of the CTW optoelectronic memristor. This work has greatly facilitated the development of optically operated artificial synaptic devices and vision bionic systems. [ABSTRACT FROM AUTHOR]