Bi2S3 holds immense potential to be promoted as an anode material for lithium-ion batteries (LIBs), owing to the high theoretical gravimetric and volumetric capacities. However, the poor electrical conductivity and volume expansion during cycling hinder the practical applications of Bi2S3. Therefore, through subsequent heat treatment, the nitrogen-doped carbon film was successfully loaded on the nanosphere Bi2S3, which we call nitrogen-rich carbon layer-coated Bi2S3 (NC@Bi2S3). Hence, the nanosphere Bi2S3 uniformly covered by a nitrogen-rich carbon layer was successfully coated on the Bi2S3 surface (NC@Bi2S3) through post-treatment. Due to the effective interaction between glutathione and inorganic materials, dopamine hydrochloride molecules are introduced and polymerized on the surface of the spherical Bi2S3 structure and then converted into a nitrogen-rich carbon layer with an average thickness of 10.0 nm. The electrochemical tests reveal that the discharge specific capacities of Bi2S3 and NC@Bi2S3 reach 340.99 and 645.13 mAh/g after 300 cycles at 100 mA/g, respectively. Kinetic analysis shows that the contribution of pseudocapacitance behavior increases by about 10% after the nitrogen-rich carbon layer is coated. These results suggest the potential of NC@Bi2S3 as a high-performance anode material for LIBs; the stability can be enhanced by core–shell structures.
Lulu Ma,Jie Wu,Shilei Wang,Hao Yang,Donghui Liang,Zhong Lu
In this paper, Bi 2 S 3 nanospheres with size of 212 nm were prepared by a simple hydrothermal process. The selectively enhanced antibacterial effects of Bi 2 S 3 nanospheres with three classes of ineffective antibiotics, β-lactam (cefuroxime, CXM; cefotaxime , CTX and piperacillin , PIP), quinolone (ciprofloxacin, CIP) and aminoglycoside (gentamicin, GEN) against clinical isolated methicillin-resistant Staphylococcus aureus (MRSA) were investigated for the first time. GEN shows significantly synergistic growth inhibition against MRSA when combined with Bi 2 S 3 nanospheres, while CXM, CTX, PIP and CIP do not. Raman spectroscopy and Z potential studies reveal that Bi 2 S 3 could interact with GEN and the combination showed small electronegativity , which probably induced the increase of GEN content in cytoplasm of bacteria. Furthermore, the combination of Bi 2 S 3 nanospheres and GEN can destroy the bacterial membrane function and induce more bactericidal reactive oxygen generation than that of Bi 2 S 3 or GEN alone. The cytotoxicity test indicates that the combination of Bi 2 S 3 and GEN presented low toxicity to human normal hepatocyte L02. This work shows that Bi 2 S 3 nanospheres can be used to enhance the action of ineffective antibiotic GEN against MRSA, thus strengthening the antibiotic capacity for fighting MRSA infections.