In
Situ Assembly of a Superaerophobic CoMn/CuNiP Heterostructure
as a Trifunctional Electrocatalyst for Ampere-Level Current Density
Urea-Assisted Hydrogen Production
posted on 2024-02-08, 04:43authored byReza Andaveh, Alireza Sabour Rouhaghdam, Abdolvahab Seif, Kun Wang, Meysam Maleki, Jianping Ai, Ghasem Barati Darband, Jinyang Li
Urea
electrolysis is a promising energy-efficient hydrogen production
process with environmental benefits, but the lack of efficient and
sustainable ampere-level current density electrocatalysts fabricated
through simple methods is a major challenge for commercialization.
Herein, we present an efficient and stable heterostructure electrocatalyst
for full urea and water electrolysis in a convenient and time-efficient
preparation manner. Overall, superhydrophilic/superaerophobic CoMn/CuNiP/NF
exhibits exceptional performance for the hydrogen evolution reaction
(HER) (−33.8, −184.4, and −234.8 mV at −10,
−500, and −1000 mA cm–2, respectively),
urea electro-oxidation reaction (UOR) [1.28, 1.43, and 1.51 V (vs
RHE) at 10, 500, and 1000 mA cm–2, respectively],
and oxygen evolution reaction (OER) [1.45, 1.67, and 1.74 V (vs RHE)
at 10, 500, and 1000 mA cm–2, respectively]. Moreover,
the superaerophobic CoMn/CuNiP/NF demonstrates promising potential
in full urea (1.33, 1.57, and 1.60 V at 10, 500, and 1000 mA cm–2, respectively) and water (1.46 V, 1.78, and 1.86
at 10, 500, and 1000 mA cm–2, respectively) electrolysis.
Based on X-ray photoelectron spectroscopy results, it was determined
that the surface of the CoMn/CuNiP electrode was rich in redox pairs
such as Ni2+/Ni3+, Cu+/Cu2+, Co2+/Co3+, and Mn2+/Mn3+, which are crucial for the formation of active sites for the OER
and UOR, such as NiOOH, MnOOH, and CoOOH, thereby enhancing the catalytic
activity. Besides, the in situ assembled CoMn/CuNiP/NF displayed highly
stable performance for HER, OER, and UOR with high Faradaic efficiency
for over 500 h. This research offers a simple and efficient method
for manufacturing a high-efficiency and stable trifunctional electrocatalyst
capable of delivering ampere-level current density in urea-assisted
hydrogen production. Our density functional theory calculations reveal
the potential of CoMn/CuNiP as an effective catalyst, enhancing the
electronic properties and catalytic performance. The near-zero Gibbs
free-energy change for HER underscores its promise, while reduced
CO2 desorption energies and charge redistribution support
efficient UOR. These findings signify CoMn/CuNiP’s potential
for electrochemical applications.