State Key Laboratory of Chem/Bio-Sensing and Chemometrics, Provincial Hunan Key Laboratory for Graphene Materials and Devices, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China.
Department of Materials Science and Engineering, Department of Chemistry, University of North Texas, Denton, TX 76203, USA.
Adv Mater. 2017 May;29(18). doi: 10.1002/adma.201606207. Epub 2017 Mar 9.
Metal-free electrocatalysts have been extensively developed to replace noble metal Pt and RuO catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in fuel cells or metal-air batteries. These electrocatalysts are usually deposited on a 3D conductive support (e.g., carbon paper or carbon cloth (CC)) to facilitate mass and electron transport. For practical applications, it is desirable to create in situ catalysts on the carbon fiber support to simplify the fabrication process for catalytic electrodes. In this study, the first example of in situ exfoliated, edge-rich, oxygen-functionalized graphene on the surface of carbon fibers using Ar plasma treatment is successfully prepared. Compared to pristine CC, the plasma-etched carbon cloth (P-CC) has a higher specific surface area and an increased number of active sites for OER and ORR. P-CC also displays good intrinsic electron conductivity and excellent mass transport. Theoretical studies show that P-CC has a low overpotential that is comparable to Pt-based catalysts, as a result of both defects and oxygen doping. This study provides a simple and effective approach for producing highly active in situ catalysts on a carbon support for OER and ORR.
金属免费电催化剂已被广泛开发，以取代贵金属 Pt 和 RuO 催化剂，用于燃料电池或金属-空气电池中的氧还原反应（ORR）和氧析出反应（OER）。这些电催化剂通常沉积在 3D 导电载体（例如，碳纸或碳布（CC））上，以促进质量和电子传输。为了实际应用，期望在碳纤维支撑体上原位生成催化剂，以简化催化电极的制造过程。在这项研究中，首次成功地使用 Ar 等离子体处理在碳纤维表面原位剥离、边缘富氧、含氧官能化的石墨烯。与原始 CC 相比，等离子体刻蚀的碳布（P-CC）具有更高的比表面积和更多的 OER 和 ORR 活性位点。P-CC 还具有良好的本征电子导电性和优异的质量传输性能。理论研究表明，由于缺陷和氧掺杂，P-CC 的过电势较低，可与基于 Pt 的催化剂相媲美。这项研究为在碳载体上原位生成高效 OER 和 ORR 催化剂提供了一种简单有效的方法。
