Enhanced UV detection of ZnSnO3 hollow spheres: Dark current inhibition from excitons and homostructures based on excitation of oxygen vacancies.

With the presence of triethanolamine (TEOA) and N,N-Dimethylformamide (DMF) as organic functional reagents, ZnSn(OH) 6 precursors composed of hollow-sphere particles were synthesized by co-precipitation method. Microstructure characterization shows that the crystallization growth of ZnSn(OH) 6 precursor can be affected by DMF, and that its particle size and average grain size are changed with the mass ratio (x) of DMF to TEOA. Each ZnSnO 3 sample (ZSO- x) from its ZnSn(OH) 6 counterpart (ZSOH- x) is amorphous structure due to the generation of oxygen vacancy defects. When x is 0.75, the resulting ZSO-0.75 sample has a higher photo-to-dark-current ratio (10,976 at 3 V) than other samples under 365 nm illumination. Further comparison indicates that although ZSO-0.75 sample has more oxygen vacancies than ZSO-0 sample, the dark current of the former is less than that of the latter at the same voltage, which may be related to the formation of tight-binding excitons and homostructures based on the thermal excitation of oxygen vacancies. [ABSTRACT FROM AUTHOR]