Shao Weide, Li Guiwei, Zheng Aodu, Wu Wenzheng, Lu Biao, Zhang Jianing, Chen Shuguang, Zhang Chunling, Zhang Feifei
Key Laboratory of Automobile Materials, Ministry of Education, School of Materials Science and Engineering, Jilin University, Changchun 130022, China.
School of Mechanical and Aerospace Engineering, Jilin University, Changchun, Jilin 130025, China.
J Colloid Interface Sci. 2025 Feb;679(Pt B):809-818. doi: 10.1016/j.jcis.2024.10.148. Epub 2024 Oct 28.
The conversion of renewable energy sources with relatively large energy fluctuations into hydrogen represents a crucial aspect of energy storage. Nevertheless, the direct water electrolysis process is known to require excessive instantaneous energy consumption and high cost. Two-step alkaline water electrolysis is regarded as a secure and effective method of generating hydrogen from renewable energy sources when compared to direct water electrolysis. Here we propose a two-step alkaline water electrolysis using nickel-cobalt based hydroxide (NiCo(OH)) as a redox mediator, and a high-performance bifunctional catalyst as gas evolution electrodes (GEE). The substrates for the GEE were prepared using 3D printing and then loaded with in-situ grown Ru-doped MoS/NiFe-LDH hierarchical heterostructure catalysts (MS-NiFe-Ru-3D). The oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) of the MS-NiFe-Ru-3D catalyst can reach up to 500 mA cm at 300 and 250 mV overpotentials, respectively. It can meet the requirement of high catalyst performance for two-step alkaline water electrolysis. The direct water electrolysis using the bifunctional MS-NiFe-Ru-3D catalyst only requires a voltage of 1.85 V at 500 mA cm with minimal attenuation over 300 h. For the two-step alkaline water electrolysis using MS-NiFe-Ru-3D as bifunctional catalysts and NiCo(OH) as redox mediator, only 1.70 V and 0.27 V were required for HER and OER at 500 mA cm, respectively. This work offers a promising avenue for the efficient conversion of renewable secondary energy sources into hydrogen.
将能量波动相对较大的可再生能源转化为氢气是能量存储的一个关键方面。然而，直接水电解过程已知需要过高的瞬时能耗和高昂成本。与直接水电解相比，两步碱性水电解被视为一种从可再生能源中制氢的安全有效的方法。在此，我们提出一种以镍钴基氢氧化物（NiCo(OH)）作为氧化还原介质，以及一种高性能双功能催化剂作为析气电极（GEE）的两步碱性水电解方法。GEE的基底采用3D打印制备，然后负载原位生长的Ru掺杂MoS/NiFe-LDH分级异质结构催化剂（MS-NiFe-Ru-3D）。MS-NiFe-Ru-3D催化剂的析氧反应（OER）和析氢反应（HER）在过电位分别为300和250 mV时，电流密度可分别达到500 mA cm。它能够满足两步碱性水电解对高催化剂性能的要求。使用双功能MS-NiFe-Ru-3D催化剂进行直接水电解时，在500 mA cm下仅需1.85 V电压，且在300 h内衰减极小。对于以MS-NiFe-Ru-3D作为双功能催化剂且NiCo(OH)作为氧化还原介质的两步碱性水电解，在500 mA cm下HER和OER分别仅需1.70 V和0.27 V。这项工作为将可再生二次能源高效转化为氢气提供了一条有前景的途径。
