Study on the Structure vs Activity of Designed Non-Precious Metal electrocatalysts for CO2 Conversion

•Alloy and core–shell bimetallic electrocatalysts nanoparticles for CO2RR designed.•The role of the metals on the catalysts’ activity/selectivity was investigated.•The bimetallic electrocatalysis outperformed the corresponding monometallic ones.•The best performance to reduce CO2 showed by the core–shell system.•The catalytic findings were rationalized by density functional calculations. This work investigates Cu and Cu-Sn nanocatalysts with controlled composition and morphology for the electrochemical CO2 reduction reaction to value-added chemicals, showing that bimetallic materials possess active sites with increased specific activity toward activation and reduction of CO2 compared to monometallic ones. While Cu showed high selectivity for the competitive hydrogen evolution reaction, bimetallic Cu-Sn electrocatalysts were selective towards CO and formates. Nanoparticles were prepared via a straightforward chemical process, leading to small, well-define and crystalline nanoparticles, either mono or bimetallic, where Cu and Sn precursors are blended in one step to achieve alloyed or core–shell structures.