Sekar Sankar, Shanmugam Atsaya, Lee Youngmin, Lee Sejoon
Division of System Semiconductor, Dongguk University, Seoul 04620, Republic of Korea.
Quantum-Functional Semiconductor Research Center, Dongguk University, Seoul 04620, Republic of Korea.
Materials (Basel). 2025 Aug 12;18(16):3775. doi: 10.3390/ma18163775.
For future clean and renewable energy technology, designing highly efficient and robust electrocatalysts is of great importance. Particularly, creating efficient bifunctional electrocatalysts capable of effectively catalyzing both hydrogen- and oxygen-evolution reactions (HERs and OERs) is vital for overall water electrolysis. In this study, we employ 2D molybdenum disulfide (MoS) nanosheets and pyrolytically fabricated 2D graphitic carbon nitride (gCN) nanosheets to create 2D gCN-decorated 2D MoS (2D-2D gCN-MoS) nanocomposites using a facile sonochemical method. The 2D-2D gCN-MoS nanocomposites show an interconnected and agglomerated structure of 2D gCN nanosheets decorated on 2D MoS nanosheets. For water electrolysis, the gCN-MoS nanocomposites exhibit low overpotentials (OER: 225 mV, HER: 156 mV), small Tafel slope values (OER: 49 mV/dec, HER: 101 mV/dec), and excellent durability (up to 100 h for both OER and HER) at 10 mA/cm in 1 M KOH. Furthermore, the gCN-MoS nanocomposites show excellent overall water electrolysis performance with a low full-cell voltage (1.52 V at 10 mA/cm) and outstanding long-term cell stability. The superb bifunctional activities of the gCN-MoS nanocomposites are attributed to the synergistic effects of 2D gCN (i.e., low charge-transfer resistance) and 2D MoS (i.e., a large electrochemically active surface area). These findings suggest that the 2D-2D gCN-MoS nanocomposites could serve as excellent bifunctional catalysts for overall water electrolysis.
对于未来的清洁和可再生能源技术而言，设计高效且稳定的电催化剂至关重要。特别是，制备能够有效催化析氢反应和析氧反应（HERs和OERs）的高效双功能电催化剂对于整体水电解至关重要。在本研究中，我们采用二维二硫化钼（MoS）纳米片和热解制备的二维石墨相氮化碳（gCN）纳米片，通过简便的超声化学方法制备二维gCN修饰的二维MoS（2D-2D gCN-MoS）纳米复合材料。2D-2D gCN-MoS纳米复合材料呈现出二维gCN纳米片装饰在二维MoS纳米片上的相互连接且团聚的结构。对于水电解，gCN-MoS纳米复合材料在1 M KOH中，10 mA/cm²时表现出低过电位（OER：225 mV，HER：156 mV）、小塔菲尔斜率值（OER：49 mV/dec，HER：101 mV/dec）以及优异的耐久性（OER和HER均高达100 h）。此外，gCN-MoS纳米复合材料在低全电池电压（10 mA/cm²时为1.52 V）下展现出优异的整体水电解性能以及出色的长期电池稳定性。gCN-MoS纳米复合材料卓越的双功能活性归因归因二维二维gCN（即低电荷转移电阻）和二维MoS（即大的电化学活性表面积）的协同效应。这些发现表明，2D-2D gCN-MoS纳米复合材料可作为整体水电解的优异双功能催化剂。
