Electrocatalytic conversion of carbon dioxide into high‐value multicarbon (C2+) chemical feedstocks offers a promising avenue to liberate the chemical industry from fossil‐resource dependence and eventually close the anthropogenic carbon cycle but is severely impeded by the lack of high‐performance catalysts. To break the linear scaling relationship of intermediate binding and minimize the kinetic barrier of CO2 reduction reactions, ternary Cu–Au/Ag nanoframes were fabricated to decouple the functions of CO generation and C−C coupling, whereby the former is promoted by the alloyed Ag/Au substrate and the latter is facilitated by the highly strained and positively charged Cu domains. Thus, C2H4 production in an H‐cell and a flow cell occurred with high Faradic efficiencies of 69±5 and 77±2 %, respectively, as well as good electrocatalytic stability and material durability. In situ IR and DFT calculations unveiled two competing pathways for C2H4 generation, of which direct CO dimerization is energetically favored.

Two-dimensional van der Waals heterostructure materials, particularly Transition Metal Dichalcogenides (TMDC), have proved to be excellent photoabsorbers for solar radiation, but performance for such electrocatalysis processes as water splitting to form H2 and O2 is not adequate.We propose that dramatically improved performance may be achieved by combining two independent TMDC while optimizing such descriptors as rotational angle, bond length, distance between layers, and the ratio of the bandgaps of two component materials can provide. In this paper we apply the Least Absolute Shrinkage and Selection Operator (LASSO) process of Artificial Intelligence incorporating these descriptors together with Quantum Mechanics (density functional theory) to predict novel structures with predicted superior performance. Our predicted best system is MoTe2/WTe2 with rotation of 300°, which is predicted to have an overpotential of 0.03 V for HER and 0.17 V for OER, dramatically improved over current electrocatalysts for water splitting.

Recently, CO2 reduction to fuels has been the subject of great much numerous studies, but selectivity and activity remain inadequate. Progress has been made on single site twodimensional catalysts based on graphene coupled to a metal and nitrogen for CO2RR but the product is usually CO and the metal-N environment remains ambiguous. We report a novel 2D graphene-nitrene heterostructure (grafiN6) providing well-defined active sites (N6) that can bind 1 to 3 metals for CO2RR. We find that homo-bimetallic FeFe-grafiN6 could reduce CO2 to CH4 at -0.61 V and to CH3CH2OH at -0.68 V vs RHE, with high product selectivity. Moreover, the heteronuclear FeCu-grafiN6 system may be significantly less affected by HER, while maintaining low limiting potential (-0.68 V) for C1 and C2 mechanisms. Binding metals to one N6 site but not the other could promote efficient electron transport facilitating some reaction steps. This framework for single multiple metal sites might also provide unique catalytic sites for other catalytic process.

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