Integrated manufacturing of REciclable multi-material COmposites for the TRANSport sector
Efficient synthesis of H2O2 via oxygen reduction over PANI driven by kinetics regulation of carbon dots
Electrocatalytic two-electron (2e?) oxygen reduction reaction (ORR) is a promising method to realize the sustainable production of H2O2. However, the 4e? pathway competes with 2e? ORR, presenting a challenge to the design of highly selective, low-cost catalysts. In addition to the design of active sites, the regulation on electrocatalytic kinetics is another strategy to get ideal 2e? ORR route. Here, cobalt doped carbon dots (CDs-Co) were used to regulate the electron transport kinetics on polyaniline (PANI) by constructing p-n heterojunction. The electron transfer kinetics and oxygen molecular activation process on PANI/CDs-Co were studied and analyzed using the transient photo-induced voltage (TPV) and pulse voltage-induced current (PVC) technologies, respectively. These results show that CDs-Co not only reduces the over-potential of oxygen molecular activation, but also reduces the transient electron concentration on PANI, which effectively improves the selectivity and activity of H2O2 production via ORR. The obtained PANI/CDs-Co-2 shows a H2O2 selectivity nearly 100.0% higher than that of PANI (76.3%). And it exhibits a H2O2 productivity of 3.5 mol g?1cat h?1 at 0 V vs. RHE tested by gas diffusion electrode device. This work provides new insights for the design of 2e? ORR catalysts and the study of electrocatalytic kinetics.
» Author: Yunjie Zhou, Xiaoqing Gu, Jie Wu, Hui Huang, Mingwang Shao, Yang Liu, Zhenhui Kang
This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement Nº 768737
