摘要
The past decade has witnessed a rapid surge of interest in the research and development of non-precious metal-based electrocatalysts for the oxygen reduction reaction （ORR）. Until now, the best catalysts in acidic electrolytes have exclusively been Fe-N-C-type materials from high-temperature pyrolysis. Despite the ORR activities of metal phthalocyanine or porphyrin macrocydes having long been known, their durability remains poor. In this work, we use these macrocycles as a basis to develop a novel organic-carbon hybrid material from in-situ polymerization of iron phthalocyanine on conductive multiwalled carbon nanotube scaffolds using a low-temperature microwave heating method. At an optimal polymer- to-carbon ratio, the hybrid electrocatalyst exhibits excellent ORR activity with a positive half-wave potential （0.80 V）, large mass activity （up to 18.0 A/g at 0.80 V）, and a low peroxide yield （〈3%）. In addition, strong electronic coupling between the polymer and carbon nanotubes is believed to suppress demetallization of the macrocycles, significantly improving cycling stability in acids. Our study represents a rare example of non-precious metal-based electrocatalysts prepared without high-temperature pyrolysis, while having ORR activity in acidic media with potential for practical applications.
The past decade has witnessed a rapid surge of interest in the research and development of non-precious metal-based electrocatalysts for the oxygen reduction reaction （ORR）. Until now, the best catalysts in acidic electrolytes have exclusively been Fe-N-C-type materials from high-temperature pyrolysis. Despite the ORR activities of metal phthalocyanine or porphyrin macrocydes having long been known, their durability remains poor. In this work, we use these macrocycles as a basis to develop a novel organic-carbon hybrid material from in-situ polymerization of iron phthalocyanine on conductive multiwalled carbon nanotube scaffolds using a low-temperature microwave heating method. At an optimal polymer- to-carbon ratio, the hybrid electrocatalyst exhibits excellent ORR activity with a positive half-wave potential （0.80 V）, large mass activity （up to 18.0 A/g at 0.80 V）, and a low peroxide yield （〈3%）. In addition, strong electronic coupling between the polymer and carbon nanotubes is believed to suppress demetallization of the macrocycles, significantly improving cycling stability in acids. Our study represents a rare example of non-precious metal-based electrocatalysts prepared without high-temperature pyrolysis, while having ORR activity in acidic media with potential for practical applications.
基金
Acknowledgements We acknowledge supports from the National Natural Science Foundation of China （Nos. 51472173, 51522208 and 21472135）, the Natural Science Foundation of Jiangsu Province （Nos. BK20140302 and SBK2015010320）, the Priority Academic Program Development of Jiangsu Higher Education Institutions and Collaborative Innovation Center of Suzhou Nano Science and Technology
