Ganguly Abhijit, McGlynn Ruairi J, Boies Adam, Maguire Paul, Mariotti Davide, Chakrabarti Supriya
School of Engineering, Ulster University, Belfast BT15 1AP, Northern Ireland, U.K.
Department of Engineering, University of Cambridge, Cambridge CB2 1PZ, U.K.
ACS Appl Mater Interfaces. 2024 Mar 13;16(10):12339-12352. doi: 10.1021/acsami.3c12944. Epub 2024 Feb 29.
Progress in electrochemical water-splitting devices as future renewable and clean energy systems requires the development of electrodes composed of efficient and earth-abundant bifunctional electrocatalysts. This study reveals a novel flexible and bifunctional electrode () by hybridizing macroscopically assembled carbon nanotube ribbons () and atmospheric plasma-synthesized NiO quantum dots (QDs) with varied loadings to demonstrate bifunctional electrocatalytic activity for stable and efficient overall water-splitting (OWS) applications. Comparative studies on the effect of different electrolytes, e.g., acid and alkaline, reveal a strong preference for alkaline electrolytes for the developed electrode, suggesting its bifunctionality for both HER and OER activities. Our proposed electrode demonstrates significantly enhanced overall catalytic performance in a two-electrode alkaline electrolyzer cell configuration by assembling the same electrode materials as both the anode and the cathode, with a remarkable long-standing stability retaining ∼100% of the initial current after a 100 h long OWS run, which is attributed to the "synergistic coupling" between NiO QD catalysts and the CNTR matrix. Interestingly, the developed electrode exhibits a cell potential () of only 1.81 V with significantly low NiO QD loading (83 μg/cm) compared to other catalyst loading values reported in the literature. This study demonstrates a potential class of carbon-based electrodes with single-metal-based bifunctional catalysts that opens up a cost-effective and large-scale pathway for further development of catalysts and their loading engineering suitable for alkaline-based OWS applications and green hydrogen generation.
作为未来可再生和清洁能源系统的电化学水分解装置的进展需要开发由高效且储量丰富的双功能电催化剂组成的电极。本研究通过将宏观组装的碳纳米管带（）与大气等离子体合成的不同负载量的NiO量子点（QDs）杂交，揭示了一种新型的柔性双功能电极（），以展示用于稳定高效全水分解（OWS）应用的双功能电催化活性。对不同电解质（例如酸和碱）影响的比较研究表明，所开发的电极对碱性电解质有强烈偏好，这表明其对析氢反应（HER）和析氧反应（OER）活性均具有双功能性。我们提出的电极通过将相同的电极材料用作阳极和阴极，在两电极碱性电解槽电池配置中展示出显著增强的整体催化性能，在100小时的OWS运行后具有出色的长期稳定性，保留了约100%的初始电流，这归因于NiO量子点催化剂与碳纳米管带基质之间的“协同耦合”。有趣的是，与文献报道的其他催化剂负载值相比，所开发的电极在NiO量子点负载量显著较低（83μg/cm）的情况下，电池电位（）仅为1.81V。本研究展示了一类具有单金属基双功能催化剂的潜在碳基电极，为进一步开发适用于碱性OWS应用和绿色制氢的催化剂及其负载工程开辟了一条经济高效的大规模途径。
