Year: 2024
Type: article
Abstract: Conventional water electrolysis relies on expensive membrane‐electrode assemblies and sluggish oxygen evolution reaction (OER) at the anode, which makes the cost of green hydrogen (H 2 ) generation much higher than that of grey H 2 . Here, we develop an innovative and efficient membrane‐free water electrolysis system to overcome these two obstacles simultaneously. This system utilizes the thermodynamically more favorable urea oxidation reaction (UOR) to generate clean N 2 over a new class of Cu‐based catalyst (Cu X O) for replacing OER, fundamentally eliminating the explosion risk of H 2 and O 2 mixing while removing the need for membranes. Notably, this membrane‐free electrolysis system exhibits the highest H 2 Faradaic efficiency among reported membrane‐free electrolysis work. In situ spectroscopic studies reveal that the new N 2 H y intermediate‐mediated UOR mechanism on the Cu X O catalyst ensures its unique N 2 selectivity and OER inertness. More importantly, an industrial‐type membrane‐free water electrolyser (MFE) based on this system successfully reduces electricity consumption to only 3.78 kWh Nm −3 , significantly lower than the 5.17 kWh Nm −3 of commercial alkaline water electrolyzers (AWE). Comprehensive techno‐economic analysis (TEA) suggests that the membrane‐free design and reduced electricity input of the MFE plants reduce the green H 2 production cost to US$1.81 kg −1 , which is lower than those of grey H 2 while meeting the technical target (US$2.00–2.50 kg −1 ) set by European Commission and United States Department of Energy.
Source: Angewandte Chemie
Authors: Xintong Gao, Pengtang Wang, Xiaogang Sun, Mietek Jaroniec, Yao Zheng, Shi‐Zhang Qiao
Institutions: The University of Adelaide, Kent State University
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W4403963387