Nano-materials & Chemistry Key Laboratory, Institute of New Materials and Industrial Technologies, Wenzhou University, Wenzhou, 325035, P. R. China.
Department of Chemistry and Biochemistry, University of Windsor, Windsor, ON, N9B3P4, Canada.
Small. 2020 Apr;16(17):e1906584. doi: 10.1002/smll.201906584. Epub 2020 Apr 2.
Heteroatom-doped carbon materials are intensively studied in supercapacitors and fuel cells, because of their great potential for sustainably bearing on the energy crisis and environmental pollution. Although enormous efforts are put in material perfection with a hierarchically porous microstructure, the simultaneous optimization of both porous structures and surface functionalities is hard to achieve due to inevitable concurrent dopant leaching effect and structural collapse under required high pyrolysis temperature. In this study, an in situ dehalogenation polymerization and activation protocol is introduced to synthesize nitrogen- and sulfur-codoped carbon materials (NS-PCMs) with hierarchical pore distribution and abundant surface doping, which endows them with good conductivity, abundant accessible active sites, and efficient mass transport. As a result, the as-prepared carbon materials (NS-a-PCM-1000) show an excellent mass specific capacitance of 461.5 F g at a current density of 0.1 A g , long cycle life (>23 k, 10 A g ), and high device energy and power density (17.3 Wh kg , 250 W kg ). Significantly, NS-a-PCM-1000 also exhibits one of the highest oxygen reduction reaction activities (onset potential of 1.0 V vs reversible hydrogen electrode) in alkaline media among all reported metal-free catalysts.
杂原子掺杂碳材料在超级电容器和燃料电池中得到了深入研究，因为它们在可持续解决能源危机和环境污染方面具有巨大的潜力。尽管在具有分级多孔微观结构的材料完善方面付出了巨大的努力，但由于不可避免的共掺杂剂浸出效应和所需的高热解温度下的结构坍塌，同时优化多孔结构和表面功能仍然难以实现。在本研究中，引入了一种原位脱卤聚合和活化方案，以合成具有分级孔分布和丰富表面掺杂的氮和硫共掺杂碳材料（NS-PCMs），这赋予了它们良好的导电性、丰富的可及活性位和有效的质量传输。结果，所制备的碳材料（NS-a-PCM-1000）在 0.1 A g 的电流密度下表现出优异的质量比电容为 461.5 F g ，长循环寿命（>23 k，10 A g ），以及高器件能量和功率密度（17.3 Wh kg ，250 W kg ）。值得注意的是，在所有报道的无金属催化剂中，NS-a-PCM-1000 在碱性介质中还表现出最高的氧还原反应活性之一（相对于可逆氢电极的起始电位为 1.0 V）。
