标题：Co9S8-Catalyzed Growth of Thin-Walled Graphite Microtubes for Robust, Efficient Overall Water Splitting
作者：Guo, Mingrui; Liu, Yi; Dong, Shun; Jiao, Xiuling; Wang, Ting; Chen, Dairong
作者机构：[Guo, Mingrui; Liu, Yi; Dong, Shun; Jiao, Xiuling; Wang, Ting; Chen, Dairong] Shandong Univ, Sch Chem & Chem Engn, Natl Engn Res Ctr Colloidal Mat, Ji 更多
通讯作者：Wang, Ting;Wang, T;Chen, DR
通讯作者地址：[Wang, T; Chen, DR]Shandong Univ, Sch Chem & Chem Engn, Natl Engn Res Ctr Colloidal Mat, Jinan 250100, Shandong, Peoples R China.
关键词：cobalt sulfide; co-doping; ferromagnetic; carbon nanotubes; water; splitting
摘要：Co9S8 crystals can catalyze the growth of thin-walled graphite microtubes (GMTs) through a catalytic chemical vapor deposition (CCVD) process using thiourea as the precursor. The growth of GMTs follows a tip-growth mechanism with tube diameters up to a few micrometer. The hollow interiors of the GMTs are filled with carbon nanotubes and wrinkled graphene layers, which form a unique nanotube/graphene-in-microtube structure. As-formed GMTs are N,S-codoped with lots of Co9S8 nanoparticles encapsulated in their inner walls. These GMTs are room-temperature ferromagnets and can be loaded on Ni foams to work as binder-free electrocatalysts with low overpotential (310 mV at 50 mA cm(-2) for the oxygen evolution reaction (OER) and 284 mV at 50 mA cm(-2) for the hydrogen evolution reaction (HER)) and long-term durability (continuous work for 120 h without loss in performance). Our research proves that metal sulfides can catalyze the growth of graphite microtubes and as-formed GMTs may potentially be used as functional building blocks to construct new kinds of electrochemical devices for various energy-related applications.