Jing Wang1, Riwei Xu1, Chengzhong Wang1, Jinping Xiong1,2. 1. Beijing Key Laboratory of Electrochemical Process and Technology for Materials, Beijing University of Chemical Technology, Beijing 100029, China. 2. Fujian Provincial Key Laboratory of Ecological Industry Green Technology, Wuyi University, Wuyishan 354399, China.
Abstract
We report on the preparation and characterization of a novel lamellar polypyrrole using an attapulgite-sulfur composite as a hard template. Pretreated attapulgite was utilized as the carrier of elemental sulfur and the attapulgite-sulfur-polypyrrole (AT @400 °C-S-PPy) composite with 50 wt.% sulfur was obtained. The structure and morphology of the composite were characterized with infrared spectroscopy (IR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). An AT @400 °C-S-PPy composite was further utilized as the cathode material for lithium-sulfur batteries. The first discharge specific capacity of this kind of battery reached 1175 mAh/g at a 0.1 C current rate and remained at 518 mAh/g after 100 cycles with capacity retention close to 44%. In the rate test, compared with the polypyrrole-sulfur (PPy-S) cathode material, the AT @400 °C-S-PPy cathode material showed lower capacity at a high current density, but it showed higher capacity when the current came back to a low current density, which was attributed to the "recycling" of pores and channels of attapulgite. Therefore, the lamellar composite with special pore structure has great value in improving the performance of lithium-sulfur batteries.
We report on the preparation and characterization of a novel lamellar polypyrrole un class="Chemical">sing an attapulgite-sulfur composite as a hard template. Pretreated attapulgite was utilized as the carrier of elemental sulfur and the attapulgite-sulfur-polypyrrole (AT @400 °C-S-PPy) composite with 50 wt.% sulfur was obtained. The structure and morphology of the composite were characterized with infrared spectroscopy (IR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). An AT @400 °C-S-PPy composite was further utilized as the cathode material for lithium-sulfur batteries. The first discharge specific capacity of this kind of battery reached 1175 mAh/g at a 0.1 C current rate and remained at 518 mAh/g after 100 cycles with capacity retention close to 44%. In the rate test, compared with the polypyrrole-sulfur (PPy-S) cathode material, the AT @400 °C-S-PPy cathode material showed lower capacity at a high current density, but it showed higher capacity when the current came back to a low current density, which was attributed to the "recycling" of pores and channels of attapulgite. Therefore, the lamellar composite with special pore structure has great value in improving the performance of lithium-sulfur batteries.