Surface and interfacial engineering of heterogeneous metal catalysts is effective and critical for optimizing selective hydrogenation for fine chemicals. By using thiol-treated ultrathin Pd nanosheets as a model catalyst, we demonstrate the development of stable, efficient, and selective Pd catalysts for semihydrogenation of internal alkynes. In the hydrogenation of 1-phenyl-1-propyne, the thiol-treated Pd nanosheets exhibited excellent catalytic selectivity (>97%) toward the semihydrogenation product (1-phenyl-1-propene). The catalyst was highly stable and showed no obvious decay in either activity or selectivity for over ten cycles. Systematic studies demonstrated that a unique Pd-sulfide/ thiolate interface created by the thiol treatment was crucial to the semihydrogenation. The high catalytic selectivity and activity benefited from the combined steric and electronic effects that inhibited the deeper hydrogenation of C=C bonds. More importantly, this thiol treatment strategy is applicable to creating highly active and selective practical catalysts from commercial Pd/C catalysts for semihydrogenation of internal alkynes.

The efficiency of splitting water into hydrogen and oxygen is highly dependent on the catalyst used. Herein, ultrathin Ni(0)‐embedded Ni(OH)2 heterostructured nanosheets, referred to as Ni/Ni(OH)2 nanosheets, with superior water splitting activity are synthesized by a partial reduction strategy. This synthetic strategy confers the heterostructured Ni/Ni(OH)2 nanosheets with abundant Ni(0)‐Ni(II) active interfaces for hydrogen evolution reaction (HER) and Ni(II) defects as transitional active sites for oxygen evolution reaction (OER). The obtained Ni/Ni(OH)2 nanosheets exhibit noble metal‐like electrocatalytic activities toward overall water splitting in alkaline condition, to offer 10 mA cm−2 in HER and OER, the required overpotentials are only 77 and 270 mV, respectively. Based on such an outstanding activity, a water splitting electrolysis cell using the Ni/Ni(OH)2 nanosheets as the cathode and anode electrocatalysts has been successfully built. When the output voltage of the electrolytic cell is 1.59 V, a current density of 10 mA cm−2 can be obtained. Moreover, the durability of Ni/Ni(OH)2 nanosheets in the alkaline electrolyte is much better than that of noble metals. No obvious performance decay is observed after 20 h of catalysis. This facile strategy paves the way for designing highly active non‐precious‐metal catalyst to generate both hydrogen and oxygen by electrolyzing water at room temperature.

Air-stable atomically thick copper nanosheets are prepared and used for selective electrochemical reduction of CO2 into CO.

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Electrochemical conversion of CO into fuels using electricity generated from renewable sources helps to create an artificial carbon cycle. However, the low efficiency and poor stability hinder the practical use of most conventional electrocatalysts. In this work, a 2D hierarchical Pd/SnO structure, ultrathin Pd nanosheets partially capped by SnO nanoparticles, is designed to enable multi-electron transfer for selective electroreduction of CO into CH OH. Such a structure design not only enhances the adsorption of CO on SnO , but also weakens the binding strength of CO on Pd due to the as-built Pd-O-Sn interfaces, which is demonstrated to be critical to improve the electrocatalytic selectivity and stability of Pd catalysts. This work provides a new strategy to improve electrochemical performance of metal-based catalysts by creating metal oxide interfaces for selective electroreduction of CO .

Aqueous zinc-ion batteries (AZIBs) are one of the promising energy storage systems, which consist of electrode materials, electrolyte, and separator. The first two have been significantly received ample development, while the prominent role of the separators in manipulating the stability of the electrode has not attracted sufficient attention. In this work, a separator (UiO-66-GF) modified by Zr-based metal organic framework for robust AZIBs is proposed. UiO-66-GF effectively enhances the transport ability of charge carriers and demonstrates preferential orientation of (002) crystal plane, which is favorable for corrosion resistance and dendrite-free zinc deposition. Consequently, Zn|UiO-66-GF-2.2|Zn cells exhibit highly reversible plating/stripping behavior with long cycle life over 1650 h at 2.0 mA cm−2, and Zn|UiO-66-GF-2.2|MnO2 cells show excellent long-term stability with capacity retention of 85% after 1000 cycles. The reasonable design and application of multifunctional metal organic frameworks modified separators provide useful guidance for constructing durable AZIBs.

3D PdCu alloy nanosheets exhibit enhanced electrocatalytic activity toward hydrogen evolution reaction and ethanol oxidation reaction in alkaline media. Simultaneous hydrogen and acetate production via a solar-powered cell for ethanol reforming has been fabricated using the nanosheets as bifunctional electrocatalysts. The device is promising for the production of both hydrogen and value-added chemicals using renewable energy.

Electrochemical partial reforming of organics provides an alternative strategy to produce valuable organic compounds while generating H2 under mild conditions. In this work, highly selective electrochemical reforming of ethanol into ethyl acetate is successfully achieved by using ultrathin Co3O4 nanosheets with exposed (111) facets as an anode catalyst. Those nanosheets were synthesized by a one-pot, templateless hydrothermal method with the use of ammonia. NH3 was demonstrated critical to the overall formation of ultrathin Co3O4 nanosheets. With abundant active sites on Co3O4 (111), the as-synthesized ultrathin Co3O4 nanosheets exhibited enhanced electrocatalytic activities toward water and ethanol oxidations in alkaline media. More importantly, over the Co3O4 nanosheets, the electrooxidation from ethanol to ethyl acetate was so selective that no other oxidation products were yielded. With such a high selectivity, an electrolyzer cell using Co3O4 nanosheets as the anode electrocatalyst and Ni–Mo nanopowders as the cathode electrocatalyst has been successfully built for ethanol reforming. The electrolyzer cell was readily driven by a 1.5 V battery to achieve the effective production of both H2 and ethyl acetate. After the bulk electrolysis, about 95% of ethanol was electrochemically reformed into ethyl acetate. This work opens up new opportunities in designing a material system for building unique devices to generate both hydrogen and high-value organics at room temperature by utilizing electric energy from renewable sources.