|
|||||
|
|
Unpaired 3d Electrons on Atomically Dispersed Cobalt Centres in Coordination Polymers Regulate both Oxygen Reduction Reaction (ORR) Activity and Selectivity for Use in Zinc–Air Batteries |
|
| Authors: | Dr Yuebin Lian Dr Wenjuan Yang Chufeng Zhang Hao Sun Prof Zhao Deng Dr Wenjie Xu Prof Li Song Prof Zhongwen Ouyang Prof Zhenxing Wang Prof Jun Guo Prof Yang Peng |
| Institution: | 1. Soochow Institute of Energy and Material Innovations, College of Physics, Optoelectronics and Energy, Soochow University, Suzhou, 215006 China
Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies, Soochow University, Suzhou, 215006 China These authors contributed equally to this work.;2. International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, 518060 China These authors contributed equally to this work.;3. Soochow Institute of Energy and Material Innovations, College of Physics, Optoelectronics and Energy, Soochow University, Suzhou, 215006 China Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies, Soochow University, Suzhou, 215006 China;4. National Synchrotron Radiation Laboratory, CAS Center for Excellence in Nanoscience, University of Science and Technology of China, Hefei, Anhui, 230029 China;5. Wuhan National High Magnetic Field Center & School of Physics, Huazhong University of Science and Technology, Wuhan, 430074 P. R. China;6. Analysis and Testing Center, Soochow University, Suzhou, 215123 China;7. Soochow Institute of Energy and Material Innovations, College of Physics, Optoelectronics and Energy, Soochow University, Suzhou, 215006 China |
| Abstract: | Reversible oxygen conversion is important for various green energy technologies. Herein we synthesize a series of bimetallic coordination polymers by varying the Ni/Co ratio and using HITP (HITP=2,3,6,7,10,11-hexaiminotriphenylene) as the ligand, to interrogate the role of metal centres in modulating the activity of the oxygen reduction reaction (ORR). Co3HITP2 and Ni3HITP2 are compared. Unpaired 3d electrons in Co3HITP2 result in less coplanarity but more radical character. Thus, despite of a reduced crystallinity and conductivity, the best ORR activity, comparable to 20 % Pt/C, is obtained for Co3HITP2, showing the 3d orbital configuration of the metal centre promotes ORR. Experimental and DFT studies show a transition of ORR pathway from four-electron for Co3HITP2 to two-electron for Ni3HITP2. Rechargeable zinc–air batteries using Co3HITP2 as the air cathode catalyst demonstrate excellent energy efficiency and stability. |
| Keywords: | 3d-Orbital-Konfiguration Flexible Elektronik Koordinationspolymere Sauerstoffreduktionsreaktion (ORR) Zink-Luft-Batterien |