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An electrically bistable and non-volatile rewritable memory effect on a sandwich architecture, ITO/PEDOT:PSS/organic–inorganic hybrid perovskite/Cu, is shown.

Porous single-crystalline (P-SC) titanium dioxide in large size would significantly enhance their photoelectrochemical functionalities owing to the structural coherence and large surface area. Here we show the growth of P-SC anatase titanium dioxide on an 2 cm scale through a conceptually different lattice reconstruction strategy by direct removal of K/P from KTiOPO 4 lattice leaving the open Ti-O skeleton simultaneously recrystallizing into titanium dioxide. The (101) facet dominates the growth of titanium dioxide while the relative titanium densities on different parent crystal facets control the microstructures. Crystal growth in reducing atmospheres produces P-SC Ti n O 2n-1 ( n = 7~38) in magneli phases with enhanced visible-infrared light absorption and conductivity. The P-SC Ti n O 2n-1 shows enhanced exciton lifetime and charge mobility. The P-SC Ti n O 2n-1 boosts photoelectrochemical oxidation of benzene to phenol with P-SC Ti 9 O 17 showing 60.1% benzene conversion and 99.6% phenol selectivity at room temperature which is the highest so far to the best of our knowledge.

Previous studies show that the metalnitrogen moieties with unsaturated nitrogen coordination numbers possess higher catalytic activities and the reported smallest nitrogen coordination number is confirmed to be ≈2 for Co-N 2 and Fe-N 2 moieties using extended X-ray absorption fine structure spectra analysis. [4][5][6] These results indeed give an in-depth insight at the atomic level into structural dependence of catalytic activity of metal nitride nanoparticles by closely correlating the average structural information with catalytic performances. However, the active metalnitrogen moieties confined at the surface layer of materials that host catalysis reactions still remain unclear.Building metal-nitrogen moieties with unsaturated nitrogen coordination numbers to enhance material's catalytic activity remains a fundamental challenge. The state-of-the-art pyrolysis technique of specific precursors is commonly used to construct metal-nitrogen moieties. However, the simultaneous presence of multiple metal species in most composite catalysts makes it highly complex to understand the nature of metal-nitrogen moieties. [7][8][9][10] The short length scale of nanostructured catalysts makes it extremely challenging to quantify metal-nitrogen moiety structure and distributions and to correspondingly elucidate the electronic structure features and unusual activity. The metal-nitrogen moieties are indeed a kind of active clusters at atomic level, which are strictly confined at lattice in local structures in crystalline composites. The polycrystalline or amorphous states of composites make it highly uncertain to construct resolved metal-nitrogen moieties and to accordingly expose these active centers on material's surfaces to host catalysis reactions. Another consideration should be given to the resolved structural feature and chemical composition of moieties that tailor electronic structures to facilitate catalysis functionalities.Single crystals with porosity, combining the advantages of long-range structural coherence of bulk crystals and large surface areas of porous materials, could provide opportunities to host the metal-nitrogen moieties with unsaturated nitrogen coordination on surface. The long-range structural coherence in single crystals offers the possibility to stabilize the metalnitrogen moieties in lattice of local structures on crystalline surfaces especially on the condition that the surface moieties have similar chemical compositions to bulk crystals. Porous Altering a material's catalytic properties would require identifying structural features that deliver electrochemically active surfaces. Single-crystalline porous materials, combining the advantages of long-range ordering of bulk crystals and large surface areas of porous materials, would create sufficient active surfaces by stabilizing 2D active moieties confined in lattice and may provide an alternative way to create high-energy surfaces for electrocatalysis that are kinetically trapped. Here, a radical concept of building active metalnitrogen moieties ...

Cephalopods can display variable body color/patterns upon environmental stimulation via bioelectricity‐controlled muscle contraction/expansion of skin chromatophores. However, it remains challenging to produce artificial display analogs that exhibit reversible and rapid switching between multiple expected luminescent patterns, although such systems are very appealing for many practical uses (e.g., data encryption). Inspired by the bioelectromechanical display tactic of cephalopods, in this work, a conceptually new photomechanically modulated fluorescent system that enables on‐demand display of fluorescent patterns via a cascading stimulation−mechanical movement−optical output conduction mechanism is presented. Specifically, this biomimetic system comprises a customizable hollow display panel and a bottom‐tethered photothermally responsive fluorescent actuator. Under NIR light, the photomechanically bending movements of the fluorescent actuator will immediately cover the hollow window of the display panel and synchronously manifest as the display of fluorescent patterns. Owing to its desirable time‐ and light‐power‐dependent actuating behaviors, diverse fluorescent patterns/information can be dynamically and reversibly displayed by facilely controlling this single remote NIR signal. This bioinspired strategy is universal and promising for fabricating on‐demand fluorescent display platforms that combine a wide choice of fluorophores, remote control with high spatial/temporal precision, and especially single‐input multiple‐output features.

Many living creatures have evolved to show diverse appearance color changes in response to multiple environmental stimuli for attraction, warning, or disguise in their environments. However, it is challenging to construct artificial soft polymer hydrogels with similar multi‐responsive multicolor tunable behaviors, but such materials can serve as soft biomimetic skins to dramatically enhance the function of certain machines. Herein, a specially designed material structure to present an innovative class of supramolecular fluorescent polymeric hydrogels with the integrated properties of wide multi‐color tunability, multi‐responsiveness, self‐healing, and remolding capacities is proposed. A key feature of this rational hydrogel design is that multiple fluorophores (blue (B) aggregation‐induced emissive and red/green (R/G) lanthanide coordinated ones) are organized separately into different polymer chains of one single supramolecular polymer network. Consequently, the B and R/G fluorophores are engineered to be orthogonally responsive, and the fluorescence intensity of each fluorophore can be controlled independently by different external stimuli, which contribute to multi‐responsive multicolor fluorescence response. Besides, the hydrogels also have satisfying self‐healing and remolding capacities. All of these promising advantages together further enabled the construction of soft biomimetic color‐changing skins that can help the existing robots achieve the desirable camouflaging function.

Conversion of photon into electron is a phenomenon of great importance in nature. Photodetectors based on this principle have immense potential applications at the frontiers of both scientific and industrial communities, thus affecting the daily life. Herein, a novel class of high‐quality organic–inorganic trihalide perovskite nanoscale hybrid photodetectors is presented based on carbon electrode−molecule junctions working at mild conditions. Almost every figure of merit with high performance, such as highest responsivity, highest photogain, high detectivity, high linear dynamic range, and a broad spectral response, could be achieved simultaneously in a single device under different biases. These significant achievements benefit from rational choices of novel energy loss‐prevented hybrid perovskite nanocrystals as active materials and optimized carbon electrode−molecule junctions as device architectures, which leads to a hybridization mechanism of photodiodes and photoconductors. These investigations demonstrate a useful photodetector platform that might lead to many future photoelectric conversion applications in the practical way.

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