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The electrochemical reduction of carbon dioxide (CO 2 ) to hydrocarbons is a potential option to achieve carbon neutrality. Although copper (Cu) shows the highest activity for the CO 2 reduction reaction (CO 2 RR) to hydrocarbons among metals, high reaction overpotentials and significant H 2 production limit its use. We investigate single-atom alloys (SAAs) of ten metals (Ag, Au, Fe, Ir, Ni, Pd, Pt, Rh, Ru, Al) on Cu(111), which is the most-favored facet on Cu for methane production, using density functional theory. We examined the dopants' ability to lower the free energy of the elementary reaction, *CO to *CHO, which is the potential-determining step (PDS). Out of the SAAs studied, only Al-doped Cu demonstrated a lowering of the PDS free energy. Additionally, weaker adsorption energies of *CO and *H on AlÀ Cu(111) suggest a preference for C 1 hydrocarbons and inhibition of H 2 evolution. Finally, activation barrier calculations for the PDS on AlÀ Cu(111) involving an explicitly hydrated proton indicated better intrinsic activity for C 1 hydrocarbons compared to pure Cu(111). We also confirmed the stability of AlÀ Cu SAA compared to small Al clusters. Through a comprehensive study of both thermodynamics and kinetics, our study presents AlÀ Cu SAA as a promising catalyst for CO 2 electroreduction to C 1 hydrocarbons.

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The objective of the present work is to develop carbon/carbon (C/C) composite bipolar plate at low cost with rapid processing time by a novel process. Carbon/carbon composite was developed using exfoliated carbon fiber reinforcement, isroaniso as primary matrix precursor, and resole type phenolic resin as secondary matrix precursor. Randomly oriented hybrid carbon fiber (T‐800 and P‐75) reinforced hybrid carbon matrix composite was fabricated. The slicing and channel forming were carried out using simple and conventional machines. The competency of the material was investigated by characterizing and analyzing density, scanning electron miscroscopy (SEM), compressive strength, compressive modulus, flexural strength, tensile strength, impact strength, hardness, electrical conductivity, thermal conductivity, coefficient of thermal expansion, permeability, and corrosion current. The C/C composite bipolar plate with exfoliated carbon fibers offered bulk density 1.75 g cm−3, tensile strength 45 MPa, flexural strength 98 MPa, compressive strength 205 MPa, electrical conductivity 190 (through‐plane) and 595 S cm−1 (in‐plane), and thermal conductivity 24 (through‐plane) and 51 W m−1 K−1 (in‐plane). Further, single cell test was performed to evaluate the effectiveness of the C/C composite bipolar plate in the PEM fuel cell and the performance was compared with the commercial graphite bipolar plate at different operating temperatures.