Hydrogen sulfide (H₂S), a toxic and corrosive byproduct of fossil fuel extraction, poses significant environmental and industrial challenges. While the conventional Claus process converts H₂S into elemental sulfur, it fails to recover hydrogen gas, missing an opportunity for sustainable energy production.
Electrocatalytic H₂S decomposition offers a promising alternative, simultaneously eliminating pollutants and producing green hydrogen under mild conditions. However, the acidic nature of H₂S deactivates non-precious metal catalysts and degrades electrode structures, resulting in a challenge to achieve both high efficiency and long-term stability.
Efficient H2S electrolysis to H2 production in the flow-cell device using chainmail integrated-electrode (Image by ZHANG Mo)
In a study published in Angew. Chem. Int. Ed., a research group led by Prof. DENG Dehui and Assoc. Prof. CUI Xiaoju from the Dalian Institute of Chemical Physics(DICP) of the Chinese Academy of Sciences (CAS), has developed a dual-level chainmail integrated-electrode that enables highly efficient hydrogen production via H2S electrolysis.
The researchers designed a graphene encapsulating nickel foam (Ni@NC foam) electrode with a dual-level chainmail structure, significantly enhancing both catalytic activity and durability. This electrode achieved an industrial-scale current density exceeding 1 A cm-2 at 1.12 V versus the reversible hydrogen electrode, which was five times higher than commercial nickel foam. Moreover, the Ni@NC foam remained stable for over 300 hours, demonstrating a lifespan at least ten times longer than commercial nickel foam electrodes.
In a simulated natural gas desulfurization test, the chainmail integrated-electrode completely oxidized and removed 20% H₂S at the anode, simultaneously producing sulfur powder. Meanwhile, high-purity hydrogen was collected at the cathode. Compared to conventional water electrolysis, the system reduced energy consumption by 43% at the current density of 200 mA cm⁻², offering a more sustainable approach to hydrogen production.
“Our study provides an efficient, low-energy solution for natural gas purification and opens up the potential of converting H₂S into valuable hydrogen fuel for industrial applications.
Link:
http://www.dicp.ac.cn/xwdt/kyjz/202503/t20250310_7550628.html
https://doi.org/10.1002/anie.202502032
