Strategy for boosting Co-Nx content for oxygen reduction reaction in aqueous metal-air batteries

2022 ◽  
Vol 520 ◽  
pp. 230891
Author(s):  
Xiangsi Wu ◽  
Chunlei Tan ◽  
Caimei He ◽  
Tong Zhao ◽  
Xianwen Wu ◽  
...  
2020 ◽  
Vol 16 (4) ◽  
pp. 625-638
Author(s):  
Leila Samiee ◽  
Sedigheh Sadegh Hassani

Background: Porous carbon materials are promising candidate supports for various applications. In a number of these applications, doping of the carbon framework with heteroatoms provides a facile route to readily tune the carbon properties. The oxygen reduction reaction (ORR), where the reaction can be catalyzed without precious metals is one of the common applications for the heteroatom-doped carbons. Therefore, heteroatom doped catalysts might have a promising potential as a cathode in Microbial fuel cells (MFCs). MFCs have a good potential to produce electricity from biological oxidization of wastes at the anode and chemical reduction at the cathode. To the best of our knowledge, no studies have been yet reported on utilizing Sulfur trioxide pyridine (STP) and CMK-3 for the preparation of (N and S) doped ordered porous carbon materials. The presence of highly ordered mesostructured and the synergistic effect of N and S atoms with specific structures enhance the oxygen adsorption due to improving the electrocatalytic activity. So the optimal catalyst, with significant stability and excellent tolerance of methanol crossover can be a promising candidate for even other storage and conversion devices. Methods: The physico-chemical properties of the prepared samples were determined by Small Angle X-ray Diffraction (SAXRD), N2 sorption-desorption, Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FESEM) and X-ray Photoelectron Spectroscopy (XPS). The prepared samples were further applied for oxygen reduction reaction (ORR) and the optimal cathode was tested with the Microbial Fuel Cell (MFC) system. Furthermore, according to structural analysis, The HRTEM, and SAXRD results confirmed the formation of well-ordered hexagonal (p6mm) arrays of mesopores in the direction of (100). The EDS and XPS approved that N and S were successfully doped into the CMK-3 carbon framework. Results: Among all the studied CMK-3 based catalysts, the catalyst prepared by STP precursor and pyrolysis at 900°C exhibited the highest ORR activity with the onset potential of 1.02 V vs. RHE and 4 electron transfer number per oxygen molecule in 0.1 M KOH. The high catalyst durability and fuel-crossover tolerance led to stable performance of the optimal cathode after 5000 s operation, while the Pt/C cathode-based was considerably degraded. Finally, the MFC system with the optimal cathode displayed 43.9 mW·m-2 peak power density showing even reasonable performance in comparison to a Pt/C 20 wt.%.cathode. Conclusions: The results revealed that the synergistic effect of nitrogen and sulfur co-doped on the carbon substrate structure leads to improvement in catalytic activity. Also, it was clearly observed that the porous structure and order level of the carbon substrate could considerably change the ORR performance.


2021 ◽  
Vol 154 (3) ◽  
pp. 034705
Author(s):  
Minchan Li ◽  
Ning Qin ◽  
Zongwei Ji ◽  
Qingmeng Gan ◽  
Zhenyu Wang ◽  
...  

Author(s):  
Dingding Li ◽  
Zheng Han ◽  
Kunyue Leng ◽  
Shenghua Ma ◽  
Yi Wang ◽  
...  

Author(s):  
Mauro C dos Santos ◽  
Lanna Lucchetti ◽  
James Almeida ◽  
Pedro Alves da Silva Autreto

The 2-electron pathway of the oxygen reduction reaction is an unwanted process in the development of fuel cells. In contrast, it has gained the scientific community’s attention due to its...


2021 ◽  
Vol 32 (8) ◽  
pp. 10349-10358
Author(s):  
Weixiang Yang ◽  
Shuihua Tang ◽  
Qiankuan Huang ◽  
Qian Zhang ◽  
Zhen Tang ◽  
...  

2021 ◽  
Vol 42 (5) ◽  
pp. 753-761
Author(s):  
Jun-Sheng Jiang ◽  
He-Lei Wei ◽  
Ai-Dong Tan ◽  
Rui Si ◽  
Wei-De Zhang ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document