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Among many alternatives, CO2 electroreduction (CO2ER) is an emerging technology to alleviate its level in the atmosphere and simultaneously to produce essential products containing high energy density using various electrocatalysts. Cu‐based mono‐ and bimetallics are electrocatalysts of concerns in this work due to the material's abundance and versatility. Intrinsic factors affecting the CO2ER are first analyzed, whereby understanding and characterizing the surface features of electrocatalysts are addressed. An X‐ray absorption spectroscopy‐based methodology is discussed to determine electronic and structural properties of electrocatalyst surface which allows the prediction of reaction mechanism and establishing the correlation with reduction products. The selectivity and faradaic efficiency of products highly depend on the quality of surface modification. Preparation and modification of electrocatalyst surfaces through various techniques are critical to increase the number of activity sites and the corresponding site activity. Mechanisms of CO2ER are complicate and thus are discussed in accordance with main products of interests. The authors try to concisely compile the most interesting, recent, and reasonable ideas that are agreeable to experimental results. Finally, this review provides an outlook for designing better Cu and Cu‐based bimetallic catalysts to obtain selective products through CO2ER.

Rechargeable aqueous zinc-ion batteries (ZIBs) are emerging as alternative lithium-ion batteries for large-scale energy storage applications due to their safety and environmental friendliness. However, their applications are hindered by the...

Designing a MoS2 catalyst having a large number of active sites and high site activity enables the catalytic activity toward the hydrogen evolution reaction to be improved. Herein, we report the synthesis of a low-cost and catalytically active immobilized single molecular molybdenum disulfide on carbonized polyacrylonitrile (MoS2-cPAN) electrocatalyst. From the extended X-ray absorption fine structure spectra analysis, we found that the as-prepared material has no metal–metal scattering and it resembles MoS2 with a molecular state. Meanwhile, the size of the molecular MoS2 has been estimated to be about 1.31 nm by high-angle annular dark-field scanning transmission electron microscopy. A low coordination number and maximum utilization of the single molecular MoS2 surface enable MoS2-cPAN to demonstrate electrochemical performance significantly better than that of bulk MoS2 by two orders of exchange current density (j o) and turnover frequency to the hydrogen evolution.

The low ionic conductivity, thermal stability and incompatibility of pellet-like solid-state electrolytes lead to low cycling performance in anode-free lithium metal batteries. Herein, we report an effective and feasible composite solid electrolyte-designing approach using the garnet (Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 , LLZTO)−polymer composite electrolyte (LLZTO/ PEO-CPE) laminated on both the anode and cathode surfaces with an ultrathin thickness of 7−10 μm by spin coating method. It is found that the LLZTO/PEO-CPE exhibits a high ionic conductivity of about 4.76 × 10 −4 S/ cm at room temperature, excellent thermal stability, and good compatibility. Moreover, it simplifies the preparation of solid electrolytes and reduces the interfacial and grain boundary resistances for ion transfer. The use of both anode and cathode laminating enables dendrite-free lithium plating on copper with a high average coulombic efficiency and cycling stability of 98.8 and 41.2%, respectively, after the 65 cycles at 0.2 mA/cm 2 and 55 °C in an anodefree battery. This work provides a new design of solid-state electrolytes (SSEs) to achieve safe and dendrite-free anode-free batteries.