Mengfan Wang1, Tao Qian1, Jinqiu Zhou1, Chenglin Yan1. 1. College of Physics, Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University , Suzhou 215006, China.
Abstract
Efficient bifunctional electrocatalysts with desirable oxygen activities are closely related to practical applications of renewable energy systems including metal-air batteries, fuel cells, and water splitting. Here a composite material derived from a combination of bimetallic zeolitic imidazolate frameworks (denoted as BMZIFs) and Fe/N/C framework was reported as an efficient bifunctional catalyst. Although BMZIF or Fe/N/C alone exhibits undesirable oxygen reaction activity, a combination of these materials shows unprecedented ORR (half-wave potential of 0.85 V as well as comparatively superior OER activities (potential@10 mA cm-2 of 1.64 V), outperforming not only a commercial Pt/C electrocatalyst but also most reported bifunctional electrocatalysts. We then tested its practical application in Zn-air batteries. The primary batteries exhibit a high peak power density of 235 mW cm-2, and the batteries are able to be operated smoothly for 100 cycles at a curent density of 10 mA cm-2. The unprecedented catalytic activity can be attritued to chemical coupling effects between Fe/N/C and BMZIF and will aid the development of highly active electrocatalysts and applications for electrochemical energy devices.
Efficient bifunctional electrocatalysts with desirable oxygen activities are closely related to practical applications of renewable energy systems including n class="Chemical">metal-air batteries, fuel cells, and water splitting. Here a composite material derived from a combination of bimetallic zeolitic imidazolate frameworks (denoted as BMZIFs) and Fe/N/C framework was reported as an efficient bifunctional catalyst. Although BMZIF or Fe/N/C alone exhibits undesirable oxygen reaction activity, a combination of these materials shows unprecedented ORR (half-wave potential of 0.85 V as well as comparatively superior OER activities (potential@10 mA cm-2 of 1.64 V), outperforming not only a commercial Pt/C electrocatalyst but also most reported bifunctional electrocatalysts. We then tested its practical application in Zn-air batteries. The primary batteries exhibit a high peak power density of 235 mW cm-2, and the batteries are able to be operated smoothly for 100 cycles at a curent density of 10 mA cm-2. The unprecedented catalytic activity can be attritued to chemical coupling effects between Fe/N/C and BMZIF and will aid the development of highly active electrocatalysts and applications for electrochemical energy devices.