Wu Xiaozhong, Yang Xinping, Feng Wei, Wang Xin, Miao Zhichao, Zhou Pengfei, Zhao Jinping, Zhou Jin, Zhuo Shuping
School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo 255049, China.
Shandong Qilu Keli Chemical Institute Co., Ltd., Zibo 255086, China.
Nanomaterials (Basel). 2021 Oct 25;11(11):2838. doi: 10.3390/nano11112838.
Phosphorus-doped hierarchically porous carbon (HPC) is prepared with the assistance of freeze-drying using colloid silica and phytic acid dipotassium salt as a hard template and phosphorus source, respectively. Intensive material characterizations show that the freeze-drying process can effectively promote the porosity of HPC. The specific surface area and P content for HPC can reach up to 892 m g and 2.78 at%, respectively. Electrochemical measurements in aqueous KOH and HSO electrolytes reveal that K of a smaller size can more easily penetrate the inner pores compared with SO, while the developed microporosity in HPC is conducive to the penetration of SO. Moreover, P-doping leads to a high operation potential of 1.5 V for an HPC-based symmetric supercapacitor, resulting in an enhanced energy density of 16.4 Wh kg. Our work provides a feasible strategy to prepare P-doped HPC with a low dosage of phosphorus source and a guide to construct a pore structure suitable for aqueous HSO electrolyte.
以胶体二氧化硅和植酸二钾盐分别作为硬模板和磷源，通过冷冻干燥辅助制备了磷掺杂分级多孔碳（HPC）。大量的材料表征表明，冷冻干燥过程能够有效促进HPC的孔隙率。HPC的比表面积和磷含量分别可达892 m²/g和2.78 at%。在KOH水溶液和H₂SO₄电解质中的电化学测量表明，与SO₄²⁻相比，较小尺寸的K⁺更容易穿透内部孔隙，而HPC中发达的微孔有利于SO₄²⁻的渗透。此外，磷掺杂使基于HPC的对称超级电容器具有1.5 V的高工作电位，从而使能量密度提高到16.4 Wh/kg。我们的工作提供了一种用低剂量磷源制备磷掺杂HPC的可行策略，并为构建适合H₂SO₄水溶液电解质的孔结构提供了指导。
