3D hierarchical porous structured carbon nanotube aerogel-supported Sn spheroidal particles: an efficient and selective catalyst for electrochemical reduction of CO2 to formate

Abstract

A 3D hierarchical porous structured carbon nanotube aerogel-supported Sn spheroidal particles (Sn/CNT-Agls) on carbon cloth (Sn/CNT-Agls/CC) electrode as a selective and efficient cathode for electrochemical reduction of CO₂ to formate is reported. The electrocatalytic activity of Sn/CNT-Agls/CC toward CO₂ reduction is greatly enhanced in comparison with carbon nanotube-supported Sn spheroidal particles (Sn/CNT) on carbon cloth (Sn/CNT/CC) electrodes, which is attributed to the high specific surface area, superior conductivity and excellent 3D hierarchical structure of Sn/CNT-Agls. A maximum faradaic efficiency of 82.7% for formate production has been achieved with high stability at −0.96 V. Strikingly, the selective CO₂ reduction to formate can occur at a low overpotential of 361 mV, and a large current density of 32.9 mA cm⁻² is obtained on the Sn/CNT-Agls/CC electrode.