WEB Tunable Heteroatom-doped Carbon as Economic and Efficient Oxygen Evolution Reaction Catalysts in Water ElectrolysisFriday (25.09.2020) 09:30 - 09:45 Z: Special Symposia I Part of:
Hydrogen fuel cell car is developed as next generation green vehicles in order to replace fossil fuel cars in near future. While the number of hydrogen fuel cell car increases, the number of hydrogen station is still limited and the cost of hydrogen fuel productions also high. In order to promote the application of hydrogen fuel cell, it is necessary to develop technologies for hydrogen production with effective and efficient route. Up-to-date, hydrogen and oxygen gases can be produced via alkaline water electrolysis (water splitting). The two-electrode system of water splitting is composed of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), taking place on the cathode and anode, respectively. One of the important reasons that keeps these systems from being of practical use to date is the sluggish kinetics of OER. OER is a four electron-proton coupled reaction while HER is only a two electron-transfer reaction, and hence it can be easily expected that OER requires a higher energy to overcome the kinetic barrier of OER to occur.Currently, noble metals or their oxide forms (Ru, Ir, RuO2, IrO2 and etc.) are known as best electrocatalysts for oxygen evolution reaction1. However, high capital cost and low durability limits their application and prompt researches to focuses on noble metal-free electrocatalysts. Among all, nitrogen, boron doped or heteroatom-doped carbon has been proved to be a potential candidate as Ir- or Ru-free catalysts.2-4 In our research, we designed and fabricated highly selective heteroatom-doped carbon catalysts as efficient and economic electrocatalysts. We have prepared both single and dual-doped heteroatom catalysts via plasma process. We applied quinoline (C9H7N) and boric acid (H3BO3) as the precursor to dope nitrogen and boron into carbon. Depending on the type of precursor, we synthesized single N-doped carbon and dual B-N doped carbon as two major electrocatalysts. The polarization curves of N-doped carbon, B-N doped carbon and commercial Ru/C electrocatalyst are plotted on Figure 1. At 10 mA/cm2, the cell voltage of N-doped carbon, B-N doped carbon and Ru/C are 1.617, 1.550 and 1.539 V vs RHE, respectively. Dual B-N doped carbon has very similar onset potential compared to that of Ru/C, and could serve as an economic and efficient OER catalysts in future.