Copper(I) oxide (Cu₂O) was electrochemically deposited on fluorine-doped tin oxide (FTO) glass electrode and covered with a thin layer of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). The electrode was studied in the photoelectrocatalytic reduction of CO₂. Methanol was obtained as the major product with a concentration of 460 μmol L⁻¹ with a photoconversion yield of 12% after 60 min of reaction under the conditions of UV-Vis (125 W Hg high pressure lamp) and application of 0.0 V vs Ag/AgCl in 3.0 mol L⁻¹ KCl in buffer sodium carbonate/sodium bicarbonate 0.1 mol L⁻¹ saturated with CO₂ gas. The PEDOT:PSS has led to a significant improvement in CO₂ conversion due to rapid transfer of photogenerated holes. Consequently, the thin layer of PEDOT:PSS also reduces the photooxidation of Cu₂O to CuO. The Cu₂O/PEDOT:PSS photocatalytic system was found to have excellent photostability. Similar yield of alcohol was observed after reusing the catalyst six times.

Graphical Abstract

氧化铜（I）（Cu ₂ O）被电化学沉积在掺氟氧化锡（FTO）玻璃电极上，并覆盖有聚（3,4-乙撑二氧噻吩）聚苯乙烯磺酸盐（PEDOT：PSS）薄层。研究了该电极在光电催化还原CO _{2中的作用}。在UV-Vis（125 W Hg高压灯）和施加0.0 V vs. Ag的条件下反应60分钟后，获得的甲醇为主要产物，浓度为460μmolL ^-1，光转化率为12％。 / AgCl在3.0 mol L ^-1的KCl缓冲液中，碳酸钠/碳酸氢钠0.1 mol L ^-1充满CO ₂气体。PEDOT：PSS显着改善了CO ₂由于光生空穴的快速转移而导致转化。因此，PEDOT：PSS的薄层也减少了Cu ₂ O向CuO的光氧化。发现Cu ₂ O / PEDOT：PSS光催化系统具有出色的光稳定性。再使用催化剂六次后，观察到相似的醇收率。

图形概要