Recently, Dr. Yan Zhang from the school of life science and engineering, Southwest Jiaotong University, as the first author and corresponding author, published a paper entitled “Self-assembly two-dimensional NiO/CeO2heterostructure rich in oxygen vacancies as efficient bifunctional electrocatalyst for alkaline hydrogen evolution and oxygen evolution" in Chemistry-A European Journal with our school as the only signature unit.
With the increasing depletion of traditional non-renewable fossil energy and the increasing environmental pollution, the development and utilization of renewable green energy is urgent. As an efficient, clean, and sustainable "carbon-free" energy, hydrogen energy has received widespread attention from all over the world, and is known as the most potential new energy source in the 21st century. Among many hydrogen production technologies, hydrogen production by electrolysis of water has the advantages of simple hydrogen production process, no pollution, and high product purity. It is a relatively mature and promising large-scale hydrogen production technology.
The water splitting reaction can be divided into two half reactions, hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). At present, platinum (Pt) and ruthenium oxide (RuO2) (or iridium oxide (IrO2) are considered to be the best catalysts for hydrogen evolution and oxygen evolution, but the scarce and expensive precious metal reserves have restricted their large-scale application in industry. The development of new low-cost, high-efficiency non-noble metal bifunctional electrocatalysts (in alkaline media) to promote the reaction, reduce overpotential, and improve energy conversion efficiency is a huge challenge in the field of electrocatalytic hydrogen production.
Now, by using a simple two-step strategy, Dr. Zhang synthesized the first two-dimensional NiO/CeO2 heterostructure material with rich oxygen vacancies, which is an efficient bifunctional electrocatalyst for alkaline hydrogen evolution and oxygen evolution
This material has many advantages:
1) The self-assembled two-dimensional structure of NiO/CeO2 has a large specific surface area, which can expose more active sites and provide a larger contact area for the electrolyte;
2) NiO/CeO2 heterogeneous The CeO2 nanoparticles in the structure can promote the adsorption and decomposition of water molecules during the hydrogen evolution reaction, and accelerate the electron transfer during the oxygen evolution reaction, thereby improving the catalytic efficiency of the catalyst;
3) The interaction between CeO2 and NiO nanoparticles can increase the number of oxygen vacancies and reduce the adsorption energy, thereby accelerating the reaction rate. Therefore, this new and efficient self-assembled two-dimensional NiO/CeO2 heterostructure material has great potential as a catalyst for hydrogen evolution and oxygen evolution in alkaline media. This work provides a theoretical and technical reference for the construction of a two-dimensional structure-based transition metal compound heterostructure material for application in the field of electrocatalysis.
The above results were published in an international journal "Chemistry-A European Journal". Dr. Zhang from our school is the first author and corresponding author. The undergraduate student Ye Fei participated in part of the work, and the research work was strongly guided by Prof. Weidong Li.
This work was supported by the Fundamental Research Funds for the Central Universities (2682020CX57).
Original link: https://doi.org/10.1002/chem.202004271
