Synthesis, characterization and electrochemical performance of Bi2S3/rice husk-based activated carbon composites as lithium ion battery anodes

This study investigates the impact of hydrothermal duration on bismuth sulfide/activated carbon composites (Bi2S3/AC) by varying the duration to 8, 24, and 48 h. The primary aim is to delineate the composite characteristics and electrochemical performance of Bi2S3/AC composites, aiming to produce anodes for lithium-ion batteries with high capacity, excellent cyclic stability, and minimal volume expansion. Activated carbon derived from rice husks was synthesized via a carbonization process and chemical activation using H3PO4 as an activator. Subsequently, the synthesis of Bi2S3/AC composites used bismuth nitrate pentahydrate and thiourea precursors through the hydrothermal method that involved three variations of hydrothermal duration: 8, 24, and 48 h, denoted as BC8, BC24, and BC48, respectively. The FTIR test indicates the presence of Bi-S, C=C, and C-O groups in the three composite products, signifying the existence of bismuth sulfide and activated carbon. The XRD result reveals orthorhombic crystal forms in the composites, while the SEM-EDX mapping illustrates particle morphologies resembling flower-like shapes. These compositions comprise Bi 74.16 %, S 11.37 %, and C 10.43 %. The GSA test suggests a mesoporous pore size in these composites. In final result, BC24 exhibits the highest electrical and ionic conductivity, measuring 2.12 x 10-3 S.cm- 1 and 2.057 x 10-4 S.cm- 1, respectively. The CV data of the BC24 composite indicates two reduction and oxidation peaks in the first cycle. Charge-discharge test on the BC24 composite exhibits a specific charge capacity of 445.51 mA.h.g-1 and a discharge capacity of 364.24 mA.h.g-1.