N-doped porous carbon nanosheets as pH-universal ORR electrocatalyst in various fuel cell devices

N-doped porous carbon nanosheets possess three dimensional (3D) hierarchical porous structures with a high surface area were prepared as high-activity ORR electrocatalysts in pH-universal electrolyte, three types of home-made fuel cells running in alkaline, acidic and neutral medium, i.e., Zn-air fuel cell, direct methanol fuel cell, and microbial fuel cell, were set up and show decent performance, demonstrating its potential to replace the high-cost Pt-based electrocatalysts for practical applications.358