September 8, 2022,Nano Research Energy, a high-starting energy journal sponsored by Tsinghua University (https://www.sciopen.com/journal/2790-8119) Youth Editorial Board,Research group of Professor Zou Xiaoxin, State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin UniversityPublished the latest review entitled “Status and perspectives of key materials for PEM electrolyzer”, which provides a comprehensive introduction to the latest research progress, existing problems and future research directions of a series of key materials (including proton exchange membranes, catalysts, membrane electrodes, gas diffusion layers and bipolar plates) in proton exchange membrane (PEM) electrolyzers.
Achieving “carbon peaking and carbon neutrality” has risen to China’s national strategy and become the general grasp of green and low-carbon energy transformation in the long term in the future.The route of coupling PEM electrolysis technology for renewable energy generation systems (“green electricity” + “green hydrogen”)It is widely regarded as one of the powerful weapons to achieve “carbon neutrality”. The PEM electrolyzer uses a proton exchange membrane to conduct protons, isolate hydrogen and oxygen evolution electrodes, have a near-zero spacing structure, and are compact in size (Figure 1), making it haveHigh current density (> 1 A/cm2), good hydrogen quality (99.99%), high energy conversion efficiency, low energy consumption, reliable operationMany of these advantages, especially the high flexibility and excellent power regulation, are very suitable for the volatility of renewable energy sources such as wind, light and water. In the face of the large-scale consumption of renewable energy and the major demand for green hydrogen production, the international hot spot has formed a hot spot for PEM electrolysis technology competition, and the International Energy Agency and large companies are laying out PEM electrolyzed water technology and application with unprecedented enthusiasm.
Figure 1 Schematic diagram of the structure of four electrolyzers. (a) Alkaline electrolyzers; (b) Proton exchange membrane electrolyzers; (c) Electrolytic cells for solid oxides; (d) Anion exchange membrane electrolyzers.
The current wide range of applications of PEM electrolyzers is limited by key materials. The core components of the PEM electrolyzer are includedBipolar plates, gas diffusion layers, proton exchange membranes, and cathode and anode electrocatalysts(Figure 2). Due to the oxidizing and corrosive working environment of PEM electrolyzers, only a few precious metal-based electrocatalysts (usually Pt and IrO2 as cathode and anode catalysts) can exhibit reasonable catalytic activity and stability in such a working environment. Secondly, bipolar plates and gas diffusion layers are usually dominated by titanium-based materials, and protective coatings of precious metals such as platinum and gold are also required. In addition, PEM as a solid electrolyte typically uses expensive Nafion-type membranes. theseThe high cost of key materials makes the hydrogen production cost of PEM electrolyzers high, and it is urgent to innovate the key materials of electrolytic cells, improve the efficiency of electrolyzed water, and reduce the cost of hydrogen production。
Figure 2 Core structure of PEM electrolyzers and key materials.
This article first introduces the PEM electrolyzer inBasic concepts of thermodynamics and dynamics, and describes the associated energy losses (including thermodynamic overpotentials, kinetic overpotentials such as activation, ohms, and mass transport); A series of proton exchange membranes, electrocatalysts, membrane electrodes, gas diffusion layers, and bipolar plates in PEM electrolyzers were then reviewedResearch progress on key components and their inactivation/stabilization mechanisms； Finally presented in the PEM electrolyzerFuture research directions for each component(Figure 3), including the development of low platinum cathode catalysts and low iridium anode catalysts, enhancing the chemical, mechanical and thermal properties of proton exchange membranes, optimizing the preparation process of membrane electrodes, adjusting the pore structure and size of the gas diffusion layer, improving the coating preparation process of bipolar plates and flow field design.
Figure 3 Future research direction of key materials of PEM electrolyzers.
Related paper information:
Zhang, K. X.; Liang, X.; Wang, L. N.; Sun, K.; Wang, Y. N.; Xie, Z. B.; Wu, Q. N.; Bai, X. Y.; Hamdy, M. S.; Chen, H.; Zou, X. X. Status and perspectives of key materials for PEM electrolyzer. Nano Res. Energy 2022, 1: e9120032. DOI: 10.26599/NRE.2022.9120032. https://doi.org/10.26599/NRE.2022.9120032
As a sister journal of Nano Research, Nano Research Energy (ISSN: 2791-0091; e-ISSN: 2790-8119; Official website: https://www.sciopen.com/journal/2790-8119It was launched in March 2022 and is co-edited by Professor Qu Liangti of Tsinghua University and Professor Chunyi Zhi of the City University of Hong Kong. Nano Research Energy is an international multidisciplinary, all-English open access journal, focusing on the cutting-edge research and application of nanomaterials and nanoscience technology in new energy-related fields, benchmarking against the top international energy journals, and committed to publishing high-level original research and review papers. Before 2023, the APC fee will be waived, and all teachers are welcome to submit articles. Please contact: NanoResearchEnergy@tup.tsinghua.edu.cn.
Special statement: This article is reproduced only for the purpose of disseminating information, and does not mean to represent the views of this website or confirm the authenticity of its contents; If other media, websites or individuals reprint from this website, they must retain the “source” indicated on this website and bear their own legal responsibilities such as copyright; If the author does not wish to be reprinted or contact us for reprint fees, please contact us.