Defect-induced optical absorption in the visible range in ZnO nanowires
نویسندگان
چکیده
The optical properties of ZnO nanowires containing defects are investigated using first-principles densityfunctional theory incorporating the LDA+U formalism. Calculations include defects in the form of substitutional N, Zn, and O vacancies as well as +1 charged O vacancy. Our calculations reveal that the presence of vacancies contribute strongly to optical absorption in the visible. Furthermore, the presence of +1 charged O vacancy is found to result in a blueshift of the absorption peaks, reducing the number of wavelengths that can be absorbed in the visible. These findings can be a useful tool for the design of new generation of materials with improved solar radiation absorption.
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