Preparation and Electrochemical Properties of Gadolinium Oxide –doped Carbon Aerogels/Sulfur Composites

A carbon aerogel (CA) was successfully synthesized by a sol-gel method combined with freeze-drying, followed by solution permeation impregnation and high-temperature carbonization to obtain a gadolinium oxide (Gd 2 O 3 )–doped CA composite (CA@Gd 2 O 3 ). Then, CA@Gd 2 O 3 was incorporated with sulfur by the melt-diffusion method to obtain CA@Gd 2 O 3 @S composites, which exhibited a superior electrochemical performance. The initial discharge specific capacity of the composite reached 1168.4 mAh/g at 0.1 C and maintained a reversible specific capacity of 814.4 mAh/g after 100 cycles. The outstanding electrochemical properties were mainly attributed to the strong polar adsorption of polysulfides by the abundant O 2- ions on the surface of Gd 2 O 3 , which inhibited the shuttle effect of polysulfides. Moreover, the CA doped with Gd 2 O 3 maintained a high specific surface area and large pore capacity to alleviate the poor electrical conductivity and volume expansion effect of sulfur cathode materials.