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In recent years, photocatalytic carbon dioxide reduction has emerged as an attractive strategy to settle the global warming and energy crisis by converting CO2 into valuable chemicals utilizing solar energy. All‐inorganic halide perovskites (PVKs), as a class of promising light‐harvesting materials with outstanding optoelectronic properties and considerable stabilities, have received dramatic attention in the field of photocatalytic CO2 reduction reaction (CO2RR). In this review, the recent progress of PVK catalysts for CO2RR is systematically summarized and evaluated according to the modification strategies and their mechanisms. The working principles of CO2RR are first introduced. The main strategies for improving the photoelectrochemical performance are then discussed and their recent developments are summarized. Finally, the current challenges, including instability, charge recombination, and insufficient active sites, and future research opportunities for further development are addressed.

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The immobilization of enzymes in metal–organic frameworks (MOFs) with preserved biofunctionality paves a promising way to solve problems regarding the stability and reusability of enzymes. However, the rational design of MOF-based biocomposites remains a considerable challenge as very little is known about the state of the enzyme, the MOF support, and their host–guest interactions upon immobilization. In this study, we elucidate the detailed host–guest interaction for MOF immobilized enzymes in the biointerface. Two enzymes with different sizes, lipase and insulin, have been immobilized in a mesoporous PCN-333(Al) MOF. The dynamic changes of local structures of the MOF host and enzyme guests have been experimentally revealed for the existence of the confinement effect to enzymes and van der Waals interaction in the biointerface between the aluminum oxo-cluster of the PCN-333 and the -NH 2 species of enzymes. This kind of host–guest interaction renders the immobilization of enzymes in PCN-333 with high affinity and highly preserved enzymatic bioactivity.

Organic-inorganic hybrid perovskites, which combine the advantages of superior optical and electronic properties and solution-processed manufacturing, have emerged as a new class of revolutionary optoelectronic devices with the potential for...

Development of efficient energy conversion and storage devices such as electrolyzers, regenerative fuel cells, and rechargeable fuel cells is vital to solve the deteriorating environmental issue caused by the consumption of fossil fuels. [1][2][3] However, the overall performance of these devices are still hindered, due to the sluggish kinetics of oxygen evolution reaction (OER) which is a complex four-electron transfer reaction. [4][5][6][7] To promote OER in the electrocatalytic overall water splitting, electrocatalysts based on noble metals and/or noble metal oxides are required. However, the large-scale production and commerical applications has been impeded by the high cost and poor stability of noble metal catalysts. [8][9][10] Therefore, it is highly desirable to exploit the readily available and cost-effective OER electrocatalysts that can replace the noble-metal-based catalysts.Metal-organic frameworks (MOFs) formed by coordination bonds between metal atom nodes and organic ligands with periodic structural units have a larger surface area (up to more than 10 000 m 2 g À1 ), more catalytic sites, and easier adjustment of structure (the metal sites and/or the organic linkers). [11] Altogether, MOFs combine the benefits of homogeneous catalysts (e.g., well-defined structure and/or ligand environment) and the heterogeneous catalysts (e.g., site isolation and/or recyclability). [12][13][14] Hence, MOFs have become promising candidates for electrocatalysts. [15,16] However, due to the poor charge transport and inappropriate intermediates absorption energy, the electrocatalytic performance of MOF materials has long been unsatisfactory. [13,17,18] To overcome these obstacles,

Recently, beyond various optoelectronic devices, lead halide perovskites have emerged as promising candidates for high‐performance photocatalysts owing to their excellent optoelectronic properties. However, most previous works on perovskite photocatalysts mainly used the forms of nanocrystals that need the perovskite‐saturated electrolyte or polycrystalline thin films that still suffer from the instability in water and low performance. Herein, the synthesis of high‐quality hybrid perovskite single crystals and their implementation as photocathodes for water splitting with a simple device structure are reported on. Optimized perovskite crystals exhibit a good water splitting photocurrent density of −0.51 mA cm−2 at 0 V versus reversible hydrogen electrode (RHE) under visible light illumination. Moreover, such devices as the p‐type photocathodes show improved stability, exhibiting no obvious decrease over 600 s. This work highlights the great potential of hybrid perovskite single crystals for photocatalyst applications in aqueous solution.

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