In₂O₃ is an effective electrocatalyst to convert CO₂ to formic acid (HCOOH), but its inherent poor electrical conductivity limits the efficient charge transfer during the reaction. Additionally, the tendency of In₂O₃ particles to agglomerate during synthesis further limits the exposure of active sites. Here we address these issues by leveraging the template effect of graphene oxide and employing InBDC as a self-sacrificing template for the pyrolysis synthesis of In₂O₃@C. The resulting In₂O₃@C/rGO-600 material features In₂O₃@C nanocubes uniformly anchored on a support of reduced graphene oxide (rGO), significantly enhancing the active sites exposure. The conductive rGO network facilitates charge transfer during electrocatalysis, and the presence of oxygen vacancies generated during pyrolysis, combined with the strong electron-donating ability of rGO, enhances the adsorption and activation of CO₂. In performance evaluation, In₂O₃@C/rGO-600 exhibits a remarkable HCOOH Faradaic efficiency exceeding 94.0% over a broad potential window of −0.7 to −1.0 V (vs. reversible hydrogen electrode (RHE)), with the highest value of 97.9% at −0.9 V (vs. RHE) in a H-cell. Moreover, the material demonstrates an excellent cathodic energy efficiency of 71.6% at −0.7 V (vs. RHE). The study underscores the efficacy of uniformly anchoring metal oxide nanoparticles onto rGO for enhancing the electrocatalytic CO₂ reduction performance of materials.

Supported Pd catalysts show superior activities for olefin productions from alkynes through semi-hydrogenation reactions, but over-hydrogenation into alkanes highly decreases olefin selectivity. Using phenylacetylene semi-hydrogenation as a model reaction, here we explore the optimization approaches toward better Pd catalysts for alkyne semi-hydrogenation through investigating support effect and metal–support interactions. The results show that the states of Pd with supports can be tuned by varying oxide reducibility, loading ratios, and post-treatments. In our system, 0.06 wt.% Pd on rutile-TiO₂ nanorods shows the highest activity owing to the synergistic effects of single-atoms and clusters. Support reducibility can change the filling degrees of Pd 4d orbitals through varying interfacial bonding strengths, which further affect catalytic activity and selectivity.