高效、廉价、稳定性和选择性好的氧还原电催化剂的研发是燃料电池大规模应用的关键.以廉价生物质——胖大海为碳源,亚甲基蓝为氮源和硫源,通过一步高温热解法,制备了氮硫共掺杂多孔碳纳米片.用X射线衍射(XRD)、扫描电镜(SEM)、能谱分析(EDS)、全自动气体吸附(BET)等表征了催化剂的物相、形貌、组成、比表面积和孔径分布,用多种电化学方法考察了材料在碱性介质中电催化氧气还原反应(ORR)的活性、稳定性和甲醇选择性.结果表明,一步热解成功制备了大比表面积的氮硫共掺杂多孔碳纳米片,该材料具有与商品Pt/C相当的电催化ORR活性,且其稳定性和甲醇选择性明显优于商品Pt/C.%It is crucial for the application of fuel cell to develop oxygen reduction catalysts with high activity,affordable cost,long-term stability and good selectivity. Nitrogen and sulfur co-doped porous carbon nanosheets were fabricated by annealing the homoge-neous mixture of sterculia lychnophora and methylene blue,where sterculia lychnophora was employed as carbon precursor and methylene blue as nitrogen and sulfur source. The phase,morphology,composition,specific surface area and pore size distribution of the prepared samples were characterized by X-ray powder diffraction(XRD),scanning electron microscope(SEM),energy disperse spectroscopy(EDS)and surface area and porosimetry system(BET). The results showed that the nitrogen and sulfur co-doped por-ous carbon nanosheets with large specific surface area were synthesized successfully by one-step pyrolysis. The material displays high catalytic activity comparable to commercial Pt/C,superior methanol crossover resistance and excellent catalytic stability for ox-ygen reduction reaction(ORR),which is much better than commercial Pt/C.
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