Molecular‐Level Design of Hierarchically Porous Carbons Codoped with Nitrogen and Phosphorus Capable of In Situ Self‐Activation for Sustainable Energy Systems

• DOI: 10.1002/smll.201602010
• Publication Date: 2016-12-14T12:06:02Z
• Authors: Wei Ai; Xuewan Wang; Chenji Zou; Zhuzhu Du; Zhanxi Fan; Hua Zhang; Peng Chen; Ting Yu; Wei Huang
• Keywords: Carbon fibers

Hierarchically porous carbons are attracting tremendous attention in sustainable energy systems, such as lithium ion battery (LIB) and fuel cell, due to their excellent transport properties that arise from the high surface area rich porosity. The state‐of‐the‐art approaches for synthesizing hierarchically normally require chemical‐ and/or template‐assisted activation techniques, which is complicate, time consuming, not feasible large scale production. Here, a molecular‐level design principle toward large‐scale synthesis of nitrogen phosphorus codoped carbon (NPHPC) through an situ self‐activation process proposed. material fabricated based on direct pyrolysis well‐designed polymer, melamine polyphosphate, capable generate specific (1479 m 2 g −1 ) hierarchical pores final NPHPC. As anode LIB, NPHPC delivers reversible capacity 1073 mAh cyclic stability 300 cycles with negligible decay. peculiar structural synergistic effect N P codopants also enable promising electrocatalyst oxygen reduction reaction, key cathodic reaction many conversion devices (for example, cells metal air batteries). Electrochemical measurements show comparable electrocatalytic performance commercial Pt/C catalyst (onset potential 0.88 V vs hydrogen electrode alkaline medium) (89.8% retention after 20 000 s continuous operation) superior methanol tolerance.