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Designing highly excellent and stable catalysts for alkaline oxygen evolution reaction (OER) is gradually pivotal for clean energy development. In this work, a heterogeneous Fe‐doped Ni(OH)2 (Ni/Fe‐0.1) was developed via simple one‐step electrodeposition onto nickel mesh. The heterogeneous interface structure generates sufficient active sites, significantly improving OER performance with an overpotential of 174 mV at 10 mA cm−2 (η10), while Tafel slope is only 43.0 mV dec−1. In particular, Ni/Fe‐0.1 is still able to operate stably at a current density of 1 A cm−2 for 100 h without obvious potential decay. The oxidation of Ni2+ to Ni3+ was detected by X‐ray photoelectron spectroscopy, proving that the heterogeneous catalyst could stabilize the high‐valence state of nickel as active sites to its superior OER performance. This work provides a convenient synthetic strategy for forming heterogeneous catalysts toward efficient water electrolysis. [ABSTRACT FROM AUTHOR]

The electrochemical reduction of carbon dioxide (CO2) to value-added multi-carbon products provides a feasible way to achieve carbon neutrality. However, enhancing the faradaic efficiency for a specific multi-carbon product like ethylene at high current densities is still a challenge. Herein, we report a Cu(II)-benzene-1,3,5-tricarboxylate coordination polymer (Cu-BTC-CP) with asymmetric building units, synthesized by a water etching strategy, for highly selective electrochemical CO2-to-C2H4 conversion. The Cu-BTC-CP catalyst achieves an ethylene faradaic efficiency as large as 65.2 ± 3% at a high current density of 350 mA cm−2 in a flow cell. Operando X-ray absorption fine structure analysis uncovers that the Cu-BTC-CP catalyst reconstructs to low-coordinated copper under reaction conditions. Density functional theory calculations further indicate that the low-coordinated Cu sites on metallic Cu surfaces are favorable for *CO intermediate coupling and promote CO2 conversion to ethylene. [ABSTRACT FROM AUTHOR]

Electrochemical CO2‐to‐CO conversion provides a possible way to address problems associated with the greenhouse effect; however, developing low‐cost electrocatalysts to mediate high‐efficiency CO2 reduction remains a challenge on account of the limited understanding of the nature of the real active sites. Herein, we reveal the Znδ+ metalloid sites as the real active sites of stable nonstoichiometric ZnOx structure derived from Zn2P2O7 through operando X‐ray absorption fine structure analysis in conjunction with evolutionary‐algorithm‐based global optimization. Furthermore, theoretical and experimental results demonstrated that Znδ+ metalloid active sites could facilitate the activation of CO2 and the hydrogenation of *CO2, thus accelerating the CO2‐to‐CO conversion. Our work establishes a critical fundamental understanding of the origin of the real active center in the zinc‐based electrocatalysts for CO2 reduction reaction. [ABSTRACT FROM AUTHOR]

Copper‐based materials are efficient electrocatalysts for the conversion of CO2 to C2+ products, and most these materials are reconstructed in situ to regenerate active species. It is a challenge to precisely design precatalysts to obtain active sites for the CO2 reduction reaction (CO2RR). Herein, we develop a strategy based on local sulfur doping of a Cu‐based metal–organic framework precatalyst, in which the stable Cu−S motif is dispersed in the framework of HKUST‐1 (S‐HKUST‐1). The precatalyst exhibits a high ethylene selectivity in an H‐type cell with a maximum faradaic efficiency (FE) of 60.0 %, and delivers a current density of 400 mA cm−2 with an ethylene FE up to 57.2 % in a flow cell. Operando X‐ray absorption results demonstrate that Cuδ+ species stabilized by the Cu−S motif exist in S‐HKUST‐1 during CO2RR. Density functional theory calculations indicate the partially oxidized Cuδ+ at the Cu/CuxSy interface is favorable for coupling of the *CO intermediate due to the modest distance between coupling sites and optimized adsorption energy. [ABSTRACT FROM AUTHOR]

Commercial nickel nanoparticles (Ni NPs) were directly converted to efficient electrocatalysts for CO2 reduction by urea–Ni solid powder pyrolysis, in which a Ni, N-co-doped graphite carbon shell wraps the Ni NPs in situ. 98.3% CO selectivity was realized with a current density of −20.2 mA cm−2 and an overpotential of 0.69 V. [ABSTRACT FROM AUTHOR]

To meet the requirements for sustainable development, photocatalytic applications including water splitting, CO2 reduction, pollutant degradation, and organic conversion reactions have become hot topics for research, due to the predictable advantages of energy storage and transportation. Metal–organic frameworks (MOFs) featured with porosity, crystallinity, and tunable constitution offer enormous potential in photocatalytic applications. Herein, a critical overview of MOFs‐based photocatalysts is presented. Following a concise introduction of the structural characteristics of MOFs, the synthesis methods of MOFs‐based photocatalysts are summarized. Moreover, subtle modification strategies for MOFs inspired by the development of other inorganic photocatalysts are also discussed on the basis of the photocatalytic mechanisms of light absorption, electron transfer, and surface catalytic reactions. Furthermore, the applications of certain MOFs‐based photocatalysts are introduced in detail. In addition, other organic frameworks‐based photocatalytic materials, such as covalent organic frameworks and covalent triazine frameworks, are also described to provide a guided insight into the rational design and fabrication of efficient frameworks‐based photocatalysts. Finally, a brief conclusion and perspective on the opportunities and challenges for the future development of MOFs‐based photocatalysts are proposed. [ABSTRACT FROM AUTHOR]

Conical morphologies with sharp tips exhibit excellent optical absorption and electric field enhancement features. We have synthesized conical structured BiVO4 crystals with a smooth curved surface and sharp tips by a simple two-phase route. The samples possess the ability to expand the visible light absorption region and are suitable for photocatalytic water oxidation. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have exhibited huge potential in the field of CO2 electroreduction but highly stable and active ones are still scarce. This study reports a (5,10,15,20-tetrakis(4-carboxyphenyl)porphyrinato)-Fe(III) chloride (FeTCPPCl) co-building UiO-66 electrocatalyst for CO2 reduction in an aqueous solution. In situ X-ray absorption spectroscopy (XAS) measurements characterized its robust structure under catalysis. The unique framework of UiO-66 provides the available proton facilitator for improving CO2 reduction activity on iron porphyrin, and a concerted proton–electron transfer (CPET) mechanism might be considered for the catalytic pathway, achieving the highest faradaic efficiency of nearly 100% at an overpotential of 450 mV for turning CO2 to CO in the reported MOFs. [ABSTRACT FROM AUTHOR]

Designing highly excellent and stable catalysts for alkaline oxygen evolution reaction (OER) is gradually pivotal for clean energy development. In this work, a heterogeneous Fe-doped Ni(OH) 2 (Ni/Fe-0.1) was developed via simple one-step electrodeposition onto nickel mesh. The heterogeneous interface structure generates sufficient active sites, significantly improving OER performance with an overpotential of 174 mV at 10 mA cm -2 (η 10 ), while Tafel slope is only 43.0 mV dec -1 . In particular, Ni/Fe-0.1 is still able to operate stably at a current density of 1 A cm -2 for 100 h without obvious potential decay. The oxidation of Ni 2+ to Ni 3+ was detected by X-ray photoelectron spectroscopy, proving that the heterogeneous catalyst could stabilize the high-valence state of nickel as active sites to its superior OER performance. This work provides a convenient synthetic strategy for forming heterogeneous catalysts toward efficient water electrolysis., (© 2023 Wiley-VCH GmbH.)

The progress of effective and durable electrocatalysts for oxygen evolution reaction (OER) is urgent, which is essential to promote the overall efficiency of green hydrogen production. To improve the performance of spinel cobalt-based oxides, which serve as promising water oxidation electrocatalysts in alkaline electrolytes, most researches have been concentrated on cations modification. Here, an anionic regulation mechanism is employed to adopt sulfur(S) anion substitution to supplant NiCo 2 O 4 by NiCo 2 S 4 , which contributed to an impressive OER performance in alkali. It is revealed that the substitution of S constructs a sub-stable spinel structure that facilitates its reconstruction into active amorphous oxysulfide under OER conditions. More importantly, as the active phase in the actual reaction process, the hetero-anionic amorphous oxysulfide has an appropriately tuned electronic structure and efficient OER electrocatalytic activity. This work demonstrates a promising approach for achieving anion conditioning-based tunable structure reconstruction for robust and easy preparation spinel oxide OER electrocatalysts., (© 2023 Wiley-VCH GmbH.)

Copper-based materials are efficient electrocatalysts for the conversion of CO 2 to C 2+ products, and most these materials are reconstructed in situ to regenerate active species. It is a challenge to precisely design precatalysts to obtain active sites for the CO 2 reduction reaction (CO 2 RR). Herein, we develop a strategy based on local sulfur doping of a Cu-based metal-organic framework precatalyst, in which the stable Cu-S motif is dispersed in the framework of HKUST-1 (S-HKUST-1). The precatalyst exhibits a high ethylene selectivity in an H-type cell with a maximum faradaic efficiency (FE) of 60.0 %, and delivers a current density of 400 mA cm -2 with an ethylene FE up to 57.2 % in a flow cell. Operando X-ray absorption results demonstrate that Cu δ+ species stabilized by the Cu-S motif exist in S-HKUST-1 during CO 2 RR. Density functional theory calculations indicate the partially oxidized Cu δ+ at the Cu/Cu x S y interface is favorable for coupling of the *CO intermediate due to the modest distance between coupling sites and optimized adsorption energy., (© 2021 Wiley-VCH GmbH.)

Commercial nickel nanoparticles (Ni NPs) were directly converted to efficient electrocatalysts for CO 2 reduction by urea-Ni solid powder pyrolysis, in which a Ni, N-co-doped graphite carbon shell wraps the Ni NPs in situ. 98.3% CO selectivity was realized with a current density of -20.2 mA cm -2 and an overpotential of 0.69 V.

A new monocarboxylic acid etching (MAE) strategy was developed for transforming chemically stable Zr-based metal-organic frameworks (MOFs) of UiO-66 to their hierarchical porous counterpart. The key design element was based on the incomplete replacement of bridging ligands in MOFs by monocarboxylic acids (MAs), leading to the departure of partial ligands and metal clusters to create mesopores in MOFs. A series of MAs with different acidity and carbon chain length were tested, and propionic acid (PA) was screened to be the suitable choice. The textural features including pore size distribution, specific surface area, and pore volume of the obtained products can be controlled by adjusting the MA concentration and reaction temperature. The obtained hierarchical porous MOFs inherited excellent stability from their parent materials. Additionally, the MAE strategy was universal to construct hierarchical porous Zr-based MOFs, and it was expanded to etch UiO-66 derivatives. The excellent adsorption behavior of the resultant hierarchical porous Zr-based MOFs over two enzymes with different size was also successfully exemplified, demonstrating their application potentials with bulky molecules involved., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Sub-3 nm ultrasmall Bi 2 Se 3 nanodots stabilized with bovine serum albumin were successfully synthesized through a reaction of hydroxyethylthioselenide with bismuth chloride in aqueous solution under ambient conditions. These nanodots exhibit a high photothermal conversion efficiency (η = 50.7%) due to their strong broad absorbance in the near-infrared (NIR) window and serve as a nanotheranostic agent for photoacoustic imaging and photothermal cancer therapy. In addition, they also display radioenhancement with a ratio of 6% due to their sensitivity to X-rays, which makes them a potential sensitizer for radiotherapy. These nanodots were also labled with radioactive 99m Tc for quantification of their biodistribution by single-photon-emission computed tomography (SPECT)/computed tomography (CT) imaging. Our work demonstrates the potential of ultrasmall Bi 2 Se 3 nanodots in multimodal imaging-guided synergetic radiophotothermal therapy of cancer.