Article

Energy-saving hydrogen production by chlorine-free hybrid seawater splitting coupling hydrazine degradation

Fu SunState Key Lab of Fine Chemicals, Liaoning Key Lab for Energy Materials and Chemical Engineering, PSU-DUT Joint Center for Energy Research, Dalian University of Technology, Dalian, ChinaJingshan QinCollege of Chemistry, Beijing University of Chemical Technology, Beijing, ChinaZhiyu WangState Key Lab of Fine Chemicals, Liaoning Key Lab for Energy Materials and Chemical Engineering, PSU-DUT Joint Center for Energy Research, Dalian University of Technology, Dalian, China. [email protected]Mengzhou YuXianhong WuState Key Lab of Fine Chemicals, Liaoning Key Lab for Energy Materials and Chemical Engineering, PSU-DUT Joint Center for Energy Research, Dalian University of Technology, Dalian, ChinaXiaoming SunCollege of Chemistry, Beijing University of Chemical Technology, Beijing, China. [email protected]Jieshan QiuCollege of Chemical Engineering, Beijing University of Chemical Technology, Beijing, China. [email protected]

2021en

ABI

Abstract

Abstract Seawater electrolysis represents a potential solution to grid-scale production of carbon-neutral hydrogen energy without reliance on freshwater. However, it is challenged by high energy costs and detrimental chlorine chemistry in complex chemical environments. Here we demonstrate chlorine-free hydrogen production by hybrid seawater splitting coupling hydrazine degradation. It yields hydrogen at a rate of 9.2 mol h –1 g cat –1 on NiCo/MXene-based electrodes with a low electricity expense of 2.75 kWh per m 3 H 2 at 500 mA cm –2 and 48% lower energy equivalent input relative to commercial alkaline water electrolysis. Chlorine electrochemistry is avoided by low cell voltages without anode protection regardless Cl – crossover. This electrolyzer meanwhile enables fast hydrazine degradation to ~3 ppb residual. Self-powered hybrid seawater electrolysis is realized by integrating low-voltage direct hydrazine fuel cells or solar cells. These findings enable further opportunities for efficient conversion of ocean resources to hydrogen fuel while removing harmful pollutants.

Identifiers

DOI: 10.1038/s41467-021-24529-3

Citations and references

Cited by 20 references

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