Sn‐based chi‐rGO/SnO 2 Nanocomposite as an Efficient Electrocatalyst for CO 2 Reduction to Formate

Designing efficient and cost‐effective electrocatalysts in simple ways is very important for energy efficiency. In this sense, nano‐sized materials have been extensively utilized for the development of efficient electrodes for electrochemical CO 2 reduction. In the present study, we have developed a Sn/chitosan‐reduced graphene oxide (chi‐rGO)/SnO 2 composite electrode via only electrochemical techniques and tested it for electrochemical reduction of CO 2 to formate. A bare Sn plate was modified with a reduced graphene oxide layer in the presence of chitosan to get a stable Sn/chi‐rGO composite structure and to get more active sites, thus an efficient reduction process was performed. The surface of the Sn/chi‐rGO composite was further modified by SnO 2 nanoparticles via the potentiostatic electrodeposition method at a fixed applied potential of −0.6 V for varying periods. The calculated double‐layer capacitance (C dl ) of the Sn/chi‐rGO/SnO 2 electrode was about 80 times larger than the bare Sn plate implying that the coexistence of SnO 2 nanoparticles on the (chi‐rGO) structure enhanced the electrochemically active sites. The maximum Faradaic efficiency was recorded as 88 % towards the production of formate at an average current density of −7.36 mAcm −2 at −1.8 V. Electrochemical measurements and the stability test revealed that the resultant Sn/chi‐rGO/SnO 2 composite structure behaves as a potential electrode material for efficient CO 2 conversion to formate.The study presents a simple and low‐cost electrode preparation procedure including only electrochemical techniques which can be conducted within a very short time and without using extra energy and chemicals/additives.