Zhu Shuyan, Tian Hao, Wang Nan, Chen Bin, Mai Yiyong, Feng Xinliang
School of Chemistry and Chemical Engineering, Shanghai Key Laboratory of Electrical Insulation and Thermal Ageing, Shanghai Jiao Tong University, 800 Dongchuan RD, Shanghai, 200240, P. R. China.
School of Materials Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan RD, Shanghai, 200240, P. R. China.
Small. 2018 Mar;14(9). doi: 10.1002/smll.201702755. Epub 2018 Jan 11.
This study develops a novel strategy, based on block copolymer self-assembly in solution, for preparing two-dimensional (2D) graphene-based mesoporous nanohybrids with well-defined large pores of tunable sizes, by employing polystyrene-block-poly(ethylene oxide) (PS-b-PEO) spherical micelles as the pore-creating template. The resultant 2D nanohybrids possess a sandwich-like structure with Fe O nanoparticle-embedded mesoporous polypyrrole (PPy) monolayers grown on both sides of reduced graphene oxide (rGO) nanosheets (denoted as mPPy-Fe O @rGO). Serving as supercapacitor electrode materials, the 2D ternary nanohybrids exhibit controllable capacitive performance depending on the pore size, with high capacitance (up to 1006 F/g at 1 A/g), good rate performance (750 F/g at 20 A/g) and excellent cycling stability. Furthermore, the pyrolysis of mPPy-Fe O @rGO at 800 °C yields 2D sandwich-like mesoporous nitrogen-doped carbon/Fe O /rGO (mNC-Fe O @rGO). The mNC-Fe O @rGO nanohybrids with a mean pore size of 12 nm show excellent electrocatalytic activity as an oxygen reduction reaction (ORR) catalyst with a four-electron transfer nature, a high half-wave-potential of +0.84 V and a limiting current density of 5.7 mA/cm , which are well comparable with those of the best commercial Pt/C catalyst. This study takes advantage of block copolymer self-assembly for the synthesis of 2D multifunctional mesoporous nanohybrids, and helps to understand the control of their structures and electrochemical performance.
本研究基于溶液中的嵌段共聚物自组装，开发了一种新策略，通过使用聚苯乙烯-嵌段-聚环氧乙烷（PS-b-PEO）球形胶束作为造孔模板，制备具有尺寸可调的明确大孔的二维（2D）石墨烯基介孔纳米杂化物。所得的二维纳米杂化物具有类似三明治的结构，在还原氧化石墨烯（rGO）纳米片的两侧生长有嵌入FeO纳米颗粒的介孔聚吡咯（PPy）单层（表示为mPPy-FeO@rGO）。作为超级电容器电极材料，二维三元纳米杂化物根据孔径表现出可控的电容性能，具有高电容（在1 A/g时高达1006 F/g）、良好的倍率性能（在20 A/g时为750 F/g）和出色的循环稳定性。此外，mPPy-FeO@rGO在800℃下热解产生二维类似三明治的介孔氮掺杂碳/FeO/rGO（mNC-FeO@rGO）。平均孔径为12 nm的mNC-FeO@rGO纳米杂化物作为具有四电子转移性质的氧还原反应（ORR）催化剂表现出优异的电催化活性，半波电位高达+0.84 V，极限电流密度为5.7 mA/cm，与最佳商业Pt/C催化剂相当。本研究利用嵌段共聚物自组装合成二维多功能介孔纳米杂化物，有助于理解其结构和电化学性能的调控。
