Gold nanoporous sponge structure is fabricated using a facile and one-step electrochemical technique without hazardous acids or bases for electrochemical reduction of CO2 to CO. The nanoporous Au shows highly selective conversion behavior for CO2 to CO. And, the CO faradaic current density on the basis of geometric area and electrochemical surface area of the nanoporous structured Au is significantly improved than the Au film, which is mainly due to highly and increased active sites at the catalytic surface. (C) 2018 Elsevier B.V. All rights reserved.