Sulfur doped-copper oxide nanoclusters synthesized through a facile electroplating process assisted by thiourea for selective photoelectrocatalytic reduction of CO.

Development of effective methods for conversion of CO to useful chemicals is considered to be a prospective way in terms of energy economy and chemical industry. Due to the thermodynamic stability of CO, the application of the low-cost eco-friendly catalyst or photocatalyts for CO reduction with high efficiency is a challenge. Herein, we report a simple template-free electrochemical approach for the preparation of sulfur doped copper oxide nanoclusters directly on the copper disc electrode using thiourea (TU) as sulfur precursor. The prepared CuO/CuO hybrid structures without TU exhibits photoelectrocatalytic fitness for CO reduction, while the catalytic activity and stability are significantly improved after sulfur substitution. Surface study by scanning electron microscopy (SEM) and atomic force microscopy (AFM) reveals an improved surface roughness alongside the formation and distribution of uniform nanoclusters of sulfur-substituted copper oxide. Also, optical analyses show a little increasing of band gap from 1.95eV to 2.05eV after sulfur substitution. Based on the experimental results, methanol and acetone are the main CO reduction products where, the overpotential of methanol and acetone evolution is in good agreement with the conduction band position of prepared nanoclusters. This work has a high competitive advantage of new sight to develop the novel doped materials via a simple way for high-performance photoelectrocatalysts for energy conversion.