On September 29th, 2025, the top international journal Nature Water published online the research on energy-environment integration by a team led by Professor Chen Guangxu and Professor Qiu Guanglei from the School of Environment and Energy at South China University of Technology (SCUT), titled “Realizing the practical application of CO₂electroreduction for urban wastewater denitrification”. This marks the first time the School of Environment and Energy has published an academic research paper as the first author unit in Nature Water.

The utilization of carbon dioxide (CO₂) is regarded as a crucial way to achieve carbon neutrality. However, a long-standing challenge has been how to directly utilize the products of electrochemical reduction without complex separation and purification. Meanwhile, the denitrification process in urban wastewater treatment requires an external carbon source, and existing commercial carbon sources (such as acetate) are costly and have application limitations. Based on this, Professor Chen Guangxu and Professor Qiu Guanglei’s team, leveraging their disciplinary expertise and experimental platforms, conducted a detailed comparison of the characteristics of CO₂ reduction reaction (CO₂RR) and urban wastewater denitrification systems. They proposed a novel integrated electrochemical-biological system that combines CO₂ electroreduction with urban wastewater denitrification.

In this system, the electrocatalytic reaction efficiently generates formate (denoted as formate-e) in a neutral electrolyte, which is directly used as a carbon source and energy carrier for microbial denitrification. Experimental results demonstrate that this system not only achieves an excellent nitrate removal rate (~3.06 mg/L/h) but also, after long-term continuous acclimation of specific microbial consortia, the denitrification effect of formate-e surpasses that of the traditional commercial carbon source acetate .Overall, this study establishes a sustainable pathway for the industrial application of CO₂RR and opens possibilities for extension to other electrochemical synthesis reactions.

SCUT is the primary affiliation for this paper. Dr. Wu Qiqi (Class of 2020), doctoral candidate Ji Sijia (Class of 2025), and Master’s graduate Chen Jinling (Class of 2021) are co-first authors. Professor Chen Guangxu and Professor Qiu Guanglei are the corresponding authors, and Professor Zhao Weiwei from Nanjing University is a co-corresponding author. This work has received substantial support from grants provided by the National Natural Science Foundation of China, Talent Programs of Guangdong Province, and the Xinghua Scholar Program.

Translated by Chen Wanmei

Initial Review by AN Yufan

Final Review by WU Zhaosheng