Cytotoxicity and First-principles Calculations of ZnS:6.25%Br Quantum Dots and Their Effect on the Growth of Aspergillus oryzae

ZnS:6.25%Br quantum dots (QDs) were fabricated by a low temperature solid phase way. The impacts of zinc vacancies ([Formula: see text]) and Br on the energetic and electronic properties of ZnS QDs were discussed by the first-principles calculations combined with the experimental results. Moreover, the cytotoxicity of ZnS:Br QDs and their influences on the growth of Aspergillus oryzae (A. oryzae) were researched. The theoretical results showed that ZnS:6.25%Br and ZnS:3.125%[Formula: see text] were n-type and p-type semiconductor, respectively, while ZnS:6.25%Br,3.125%[Formula: see text] was a neutral semiconductor. It was found that ZnS:6.25%Br QDs were not only nontoxic for HeLa cells but also promoted the growth of A. oryzae. This work will provide a new method for improving the growth of A. oryzae.