Hybrid electrodes are widely used in various energy storage and conversion devices. However, conventional fabrication methods like simple mixing allow only limited control over the internal electrode structure, and it is often difficult to elucidate the structure-property relationship among the electrode components. Taking advantage of the versatile layer-by-layer (LbL) assembly method, herein we report the preparation of electrocatalytic thin film electrodes for hydrogen evolution reaction (HER), highlighting the importance of nanoscale composition in multidimensional hybrid electrodes. The fabrication utilized the electrostatic interaction between the two components: catalytically active two-dimensional MoS2 nanosheets and conductive, one-dimensional multiwalled carbon nanotube (MWNT) support. The electrocatalytic activity was found to be highly tunable by adjusting the thickness of the electrode, suggesting structural dependence of electron transfer and mass transport between the electrolyte and electrode, which is otherwise difficult to investigate in electrodes fabricated by simple conventional methods. Furthermore, the detailed mechanism of HER on the hybrid electrode was also investigated, revealing the fine balance between the catalytic activity of MoS2 and conductivity of MWNT. We anticipate that this unique approach will offer new insights into the nanoscale control of electrode architecture and the development of novel electroactive catalysts.
Bibliographical noteFunding Information:
This work was supported by a National Research Foundation of Korea (NRF) grant (NRF-2014R1A2A1A11052829). E.A. acknowledges financial support from the Global Ph.D. Fellowship funded by National Research Foundation of Korea (NRF-2013H1A2A1033508). We thank Minsu Gu for assistance with QCM analysis and Youngkyu Choi and Yuju Jeon for assistance with FT-IR and SEM, respectively. We would also like to extend our gratitude to Piljae Joo for active discussion on the project.
© 2017 American Chemical Society.
All Science Journal Classification (ASJC) codes
- Materials Science(all)