Related Experiment Video
Updated: Jun 21, 2025

Hydrogen Production and Utilization in a Membrane Reactor
Published on: March 10, 2023
Highly selective urea electrooxidation coupled with efficient hydrogen evolution
Guangming Zhan1, Lufa Hu1, Hao Li2
1School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, P. R. China.
Atomically isolated Ni-O-Ti sites enable highly selective electrochemical urea oxidation to nitrogen gas (N2), a key step for sustainable hydrogen production and wastewater treatment. This breakthrough overcomes limitations of previous catalysts, paving the way for efficient decentralized systems.
Area of Science:
- Electrochemistry
- Materials Science
- Sustainable Energy
Background:
- Electrochemical urea oxidation is a promising route for hydrogen (H2) production and wastewater denitrification.
- Current methods are hindered by the formation of undesirable byproducts like cyanate or nitrite instead of nitrogen gas (N2).
- Existing nickel-based electrocatalysts exhibit limited N2 selectivity, often below 55%.
Purpose of the Study:
- To develop an electrocatalyst for highly selective urea oxidation to N2.
- To improve hydrogen production efficiency and wastewater treatment.
- To enable decentralized, solar-powered urine processing.
Main Methods:
- Fabrication of atomically isolated asymmetric Ni-O-Ti sites on a titanium (Ti) foam anode.
- Electrochemical characterization of the catalyst's performance in urea oxidation.
- Coupling the anode with a platinum (Pt) cathode for hydrogen evolution.
- Integration into a prototype device powered by a silicon (Si) photovoltaic cell.
Main Results:
- Achieved 99% N2 selectivity in electrochemical urea oxidation, significantly outperforming Ni-O-Ni counterparts.
- Demonstrated a hydrogen evolution rate of 22.0 mL h⁻¹ at a high current density (213 mA cm⁻²) and potential (1.40 VRHE).
- The asymmetric Ni-O-Ti sites facilitate urea interaction, preventing C-N bond cleavage and promoting N-N coupling for N2 formation.
- A functional prototype device demonstrated solar-powered, on-site urine processing and decentralized H2 production.
Conclusions:
- Atomically isolated asymmetric Ni-O-Ti sites are highly effective for selective urea oxidation to N2.
- This advancement addresses key limitations in electrochemical urea oxidation for water-energy nexus applications.
- The developed technology offers a sustainable solution for decentralized hydrogen production and urine treatment.
More Related Videos
06:39Author Spotlight: Design and Evaluation of Au-Electroplated Carbon Fiber Cloth Electrodes for Hydrogen Peroxide Fuel Cells
Published on: October 20, 2023
09:18Simple Methods for the Preparation of Non-noble Metal Bulk-electrodes for Electrocatalytic Applications
Published on: June 21, 2017
Related Concept Videos
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
Catalysis
Reduction of Alkenes: Catalytic Hydrogenation
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
Amines to Alkenes: Hofmann Elimination
Under thermal conditions, the hydroxide can abstract a proton from the β carbon; this generates an alkene with the simultaneous...