Herein, we report a series of CuPd catalysts for electrochemical hydrogenation (ECH) of furfural to 2‐methylfuran (MF or FurCH3 where Fur=furyl) in aqueous 0.1 M acetic acid (pH 2.9). The highest faradaic efficiency (FE) for MF reached 75 % at −0.58 V vs. reversible hydrogen electrode with an average partial current density of 4.5 mA cm−2. In situ surface‐enhanced Raman spectroscopic and kinetic isotopic experiments suggested that electrogenerated adsorbed hydrogen (Hads) was involved in the reaction and incorporation of Pd enhanced the surface coverage of Hads and optimized the adsorption pattern of furfural, leading to a higher FE for MF. Density functional theory calculations revealed that Pd incorporation reduced the energy barrier for the hydrogenation of FurCH2* to FurCH3*. Our study demonstrates that catalyst surface structure/composition plays a crucial role in determining the selectivity in ECH and provides a new strategy for designing advanced catalysts for ECH of bio‐derived oxygenates.

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Cu is a catalyst that can electrochemically reduce CO 2 to a variety of industrially important carbon products, but often with poor selectivity and low current density. Alloying Cu with other metals provides a useful strategy to tune product selectivity. In this study, four different metal hydroxides were deposited onto Cu(OH) 2 sub-micronsized rods (SMRs) that were grown on a copper foam by an inexpensive and facile method. This procedure was followed by dehydration to form MO x (M = Cd, Sb, Pb, Zn) on a Cu y O SMR surface and then electrochemically reduced to form MCu on the Cu SMR surface. Use of these materials for CO 2 reduction achieves enhancement in formate selectivity in the order of Cd > Sb > Pb > Zn with excellent current density (∼30 mA cm −2 ). The role of the four materials in tuning the selectivity toward formate during electrochemical CO 2 reduction on these modified Cu SMRs is elucidated.

To mitigate flooding associated with the gas diffusion layer (GDL) during electroreduction of CO 2 , we report a hydrophobicity-graded hydrophobic GDL (HGGDL). Coating uniformly dispersed polytetrafluoroethylene (PTFE) binders on the carbon fiber skeleton of a hydrophilic GDL uniformizes the hydrophobicity of the GDL and also alleviates the gas blockage of pore channels. Further adherence of the PTFE macroporous layer (PMPL) to one side of the hydrophobic carbon fiber skeleton was aided by sintering. The introduced PMPL shows an appropriate pore size and enhanced hydrophobicity. As a result, the HGGDL offers spatial control of the hydrophobicity and hence water and gas transport over the GDL. Using a nickel-single-atom catalyst, the resulting HGGDL electrode provided a CO faradaic efficiency of over 83 % at a constant current density of 75 mA cm À 2 for 103 h operation in a membrane electrode assembly, which is more than 16 times that achieved with a commercial GDL.