Park Gi Dae, Choi Seung Ho, Lee Jung-Kul, Kang Yun Chan
Department of Materials Science and Engineering, Korea University, Anam-Dong, Seongbuk-Gu, Seoul 136-713 (Korea), Fax: (+82) 2-928-3584.
Chemistry. 2014 Sep 15;20(38):12183-9. doi: 10.1002/chem.201403471. Epub 2014 Aug 8.
A facile, one-pot method for synthesizing spherical-like metal sulfide-reduced graphene oxide (RGO) composite powders by spray pyrolysis is reported. The direct sulfidation of ZnO nanocrystals decorated on spherical-like RGO powders resulted in ZnS-RGO composite powders. ZnS nanocrystals with a size below 20 nm were uniformly dispersed on spherical-like RGO balls. The discharge capacities of the ZnS-RGO, ZnO-RGO, bare ZnS, and bare ZnO powders at a current density of 1000 mA g(-1) after 300 cycles were 628, 476, 230, and 168 mA h g(-1), respectively, and the corresponding capacity retentions measured after the first cycles were 93, 70, 40, and 21 %, respectively. The discharge capacity of the ZnS-RGO composite powders at a high current density of 4000 mA g(-1) after 700 cycles was 437 mA h g(-1). The structural stability of the highly conductive ZnS-RGO composite powders with ultrafine crystals during cycling resulted in excellent electrochemical properties.
报道了一种通过喷雾热解合成球形金属硫化物-还原氧化石墨烯（RGO）复合粉末的简便一锅法。球形RGO粉末上装饰的ZnO纳米晶体直接硫化得到ZnS-RGO复合粉末。尺寸小于20 nm的ZnS纳米晶体均匀分散在球形RGO球上。在1000 mA g(-1)的电流密度下循环300次后，ZnS-RGO、ZnO-RGO、裸ZnS和裸ZnO粉末的放电容量分别为628、476、230和168 mA h g(-1)，第一次循环后测量的相应容量保持率分别为93%、70%、40%和21%。在4000 mA g(-1)的高电流密度下循环700次后，ZnS-RGO复合粉末的放电容量为437 mA h g(-1)。具有超细晶体的高导电ZnS-RGO复合粉末在循环过程中的结构稳定性导致了优异的电化学性能。
