Precious-metal-free rGO/NiMnB nanoarchitectonics with covalent metal support interaction for efficient and durable alkaline water splitting
Year: 2025
Type: article
Abstract: To accelerate the widespread adoption of green hydrogen energy, developing cost-effective, sustainable electrocatalysts that can replace precious metals is essential. This study introduces a bifunctional electrocatalyst for overall water splitting, comprising 2D reduced graphene oxide (rGO) integrated with NiMnB nanosheets into a tailored nanohybrid (rGO/Ni 1.5 Mn 0.5 B). The integration enhances both crystal growth and catalytic activity by promoting rapid nucleation and efficient electron transport. Synthesized via a one-pot hydrothermal process, the rGO/Ni 1.5 Mn 0.5 B electrode exhibits a crystalline 2D nanosheet-like morphology, ensuring high electroactive surface area and strong contact with electrolyte. In 1.0 M KOH, the catalyst achieves an overpotential of 159 mV for hydrogen evolution reaction (HER) and 170 mV for oxygen evolution reaction (OER), outperforming RuO 2 at 10 mA/cm 2 . DFT calculations reveal that the strong orbital coupling between Ni, Mn, and the rGO matrix enhances metal-support interactions, boosting catalytic performance. The symmetric cell demonstrates overall water splitting cell voltage of 1.49 V at 10 mA/cm 2 with excellent durability over 20 h under industrial conditions. Additionally, the long-term durability performance was evaluated using time series modelling with a long short-term memory algorithm. With superior electronic, structural, and electrochemical properties, rGO/Ni 1.5 Mn 0.5 B offers a scalable solution for next-generation industrial water splitting and sustainable hydrogen production. Graphical abstract A bifunctional, precious-metal-free rGO/NiMnB nanohybrid exhibits enhanced alkaline water splitting performance via covalent metal-support interactions. Synergistic orbital coupling at the Fermi level promotes efficient electron transfer, leading to low overpotentials for HER and OER. DFT analysis supports the observed catalytic activity and stability under industrial conditions.
Source: Nano Convergence
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,990
Funders: National Research Foundation, Ministry of Trade, Industry and Energy, National Research Foundation of Korea, Khalifa University of Science, Technology and Research, Ministry of Science and ICT, South Korea, Korea Institute of Energy Technology Evaluation and Planning, National Supercomputing Center, Korea Institute of Science and Technology Information
OpenAlex ID: W4415604045