Ding Hui, Liu Dejiang, Liu Xia, Zhang Li, Xu Guancheng
State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi 830017, Xinjiang, PR China.
State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi 830017, Xinjiang, PR China; College of Chemical Engineering, Xinjiang University, Urumqi 830017, Xinjiang, PR China.
J Colloid Interface Sci. 2025 Mar 15;682:392-402. doi: 10.1016/j.jcis.2024.11.197. Epub 2024 Nov 26.
Maximizing the utilization of active sites and tuning the electronic-state are crucial yet extremely challenging in enhancing the ability of alloy-based catalysts to catalyze hydrogen and oxygen evolution reactions (HER and OER). Here, the 3D self-supported N-doped carbon nanotube arrays (NCNTAs) was synthesized on Ni foam by the drop-casting and calcination method, where the metal Co and CoFe alloy were enclosed at the NCNT tip (denoted as Co/CoFe@NCNT/NF). The Co/CoFe hetero-interface formation led to changes in the electronic state, which can optimize the adsorption free energy of reaction intermediates and thereby boost the intrinsic catalytic performance. The well-dispersed carbon nanotube arrays with superhydrophilic and superaerophobic characteristic promotes electrolyte permeation and bubbles escape. Therefore, the optimized Co/CoFe-10@NCNT/NF exhibits superior bifunctional activities with overpotential of 93 and 174 mV at 10 mA cm for HER and OER, respectively. For overall water splitting (OWS), the assembled dual electrode device with Co/CoFe-10@NCNT/NF only requires a low voltage of 1.56 V to achieve 10 mA cm and stabilizes for 24 h at 100 mA cm. The result underscores the importance of hetero-interface electronic effect and carbon nanotube arrays in catalytic water splitting, providing valuable insights for the design of more advanced bifunctional electrocatalysts for OWS.
在提高合金基催化剂催化析氢反应和析氧反应（HER和OER）的能力方面，最大化活性位点的利用率和调节电子态至关重要但极具挑战性。在此，通过滴铸和煅烧法在泡沫镍上合成了三维自支撑氮掺杂碳纳米管阵列（NCNTAs），其中金属Co和CoFe合金被包裹在NCNT尖端（表示为Co/CoFe@NCNT/NF）。Co/CoFe异质界面的形成导致电子态发生变化，这可以优化反应中间体的吸附自由能，从而提高本征催化性能。具有超亲水和超疏气特性的分散良好的碳纳米管阵列促进了电解质渗透和气泡逸出。因此，优化后的Co/CoFe-10@NCNT/NF表现出优异的双功能活性，在10 mA cm下HER和OER的过电位分别为93和174 mV。对于全水解（OWS），由Co/CoFe-10@NCNT/NF组装的双电极装置仅需1.56 V的低电压即可实现10 mA cm，并在100 mA cm下稳定24 h。该结果强调了异质界面电子效应和碳纳米管阵列在催化水分解中的重要性，为设计更先进的OWS双功能电催化剂提供了有价值的见解。
