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Platinum (Pt)‐based electrocatalysts are the benchmark catalysts for hydrogen evolution reaction (HER); however, they are limited by the scarcity and high price. Introducing an adequate substrate to disperse and anchor Pt‐based species is a feasible pathway to improve the utilization efficiency. Herein, a quick and continuous spray drying route is proposed to fabricate 3D crumpled Ti3C2Tx MXene loaded with sub‐nanometer platinum clusters (Pt/MXene). The 3D crumpled structure inhibits the restacking of layered MXene nanosheets and guarantees the fully exposure of Pt clusters. The as‐prepared catalyst exhibits excellent HER performances comparable to commercial Pt/C, including a low overpotential of 34 mV to reach a current density of 10 mA cm−2, a superior mass activity (1847 mA mgPt−1), a small Tafel slope (29.7 mV dec−1), and a high turnover frequency (10.66 H2 s−1). The improved activity of Pt/MXene can be attributed to the charge transfer from Pt clusters to MXene, which weakens the hydrogen adsorption, as evidenced by the density functional theory calculations. The present contribution proposes a novel strategy to anchor low‐mass‐loading sub‐nanometer precious metal clusters on crumpled MXene with fully exposed active sites for catalysis. [ABSTRACT FROM AUTHOR]

Hydrogen spillover has attracted increasing interests in the field of electrocatalytic hydrogen evolution reaction (HER) in recent years because of their distinct reaction mechanism and beneficial terms for simultaneously weakening the strong hydrogen adsorption on metal and strengthening the weak hydrogen adsorption on support. By taking advantageous merits of efficient hydrogen transfer, hydrogen spillover‐based binary catalysts have been widely investigated, which paves a new way for boosting the development of hydrogen production by water electrolysis. In this paper, we summarize the recent progress of this interesting field by focusing on the advanced strategies for intensifying the hydrogen spillover towards HER. In addition, the challenging issues and some perspective insights in the future development of hydrogen spillover‐based electrocatalysts are also systematically discussed. [ABSTRACT FROM AUTHOR]

In this paper, the properties and evolution during the calcination process of hydrolysis by−products from the reaction between Al−based composites and water for hydrogen generation were systematically investigated. The results showed that the main phases of by−products included AlOOH and InSn4. The amorphous product possessed a large Brunauer−Emmett−Teller (BET) surface area with 276.77 m2/g and high porosity properties with 0.37 cm3/g. The phase transformation of by−products from AlOOH to γ−Al2O3, δ−Al2O3, and α−Al2O3 occurred during the calcination process. It appears that the by−products can be used as raw materials for the preparation of Al2O3 with different crystal structures. Discussion on the properties and evolution of hydrolysis by−products are beneficial to product reuse and recovery. In this way, the cost reduction of hydrogen production via Al−water reaction can be realized, promoting the sustainable development of hydrogen production from Al−water reaction. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) metal–organic framework (MOF) membranes are considered potential gas separation membranes of the next generation due to their structural diversity and geometrical functionality. However, achieving a rational structure design for a 2D MOF membrane and understanding the impact of MOF nanosheet stacking modes on membrane separation performance remain challenging tasks. Here, we report a novel kind of 2D MOF membrane based on [Cu2Br(IN)2]n (IN=isonicotinato) nanosheets and propose that synergetic stacking modes of nanosheets have a significant influence on gas separation performance. The stacking of the 2D MOF nanosheets is controlled by solvent droplet dynamic behaviors at different temperatures of drop coating. Our 2D MOF nanosheet membranes exhibit high gas separation performances for H2/CH4 (selectivity >290 with H2 permeance >520 GPU) and H2/CO2 (selectivity >190 with H2 permeance >590 GPU) surpassing the Robeson upper bounds, paving a potential way for eco‐friendly H2 separation. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) metal–organic framework (MOF) membranes are considered potential gas separation membranes of the next generation due to their structural diversity and geometrical functionality. However, achieving a rational structure design for a 2D MOF membrane and understanding the impact of MOF nanosheet stacking modes on membrane separation performance remain challenging tasks. Here, we report a novel kind of 2D MOF membrane based on [Cu2Br(IN)2]n (IN=isonicotinato) nanosheets and propose that synergetic stacking modes of nanosheets have a significant influence on gas separation performance. The stacking of the 2D MOF nanosheets is controlled by solvent droplet dynamic behaviors at different temperatures of drop coating. Our 2D MOF nanosheet membranes exhibit high gas separation performances for H2/CH4 (selectivity >290 with H2 permeance >520 GPU) and H2/CO2 (selectivity >190 with H2 permeance >590 GPU) surpassing the Robeson upper bounds, paving a potential way for eco‐friendly H2 separation. [ABSTRACT FROM AUTHOR]

Introducing vacancies and element doping are effective approaches to boost photocatalytic activities of metal sulfides. In this work, sulfur vacancies and nickel dopants were simultaneously introduced into ultrathin ZnIn2S4 nanosheets (ZIS NSs) to explore their synergistic role in promoting photocatalytic hydrogen evolution. The S vacancies can trap the photo‐generated electrons, lower the conduction band minimum (CBM), improve the photo‐generated charge reduction capacity and prolong the carrier lifetime. Meanwhile, Ni dopants cause an increase in the Fermi level (EF), which ensures a higher charge density and an effective carrier separation efficiency. The optimum hydrogen evolution rate of sample Ni0.05−VS−ZIS reaches 8.91 mmol g−1 h−1 under visible light due to the synergistic effect of the S vacancies and Ni dopants. [ABSTRACT FROM AUTHOR]