Abstract
GaOOH/reduced graphene oxide (rGO) composites are investigated for UVC photodetection with a defect-controlled photoresponse. The morphology and crystallinity of GaOOH grown on rGO are strongly influenced by the Ga(NO3)3 concentration. Excess precursor induces GaOOH aggregation, reducing the effective GaOOH/rGO interfacial area and generating trap states in GaOOH. These traps act as recombination centers that shorten the carrier lifetime and suppress the photocurrent. The optimized 10% Ga(NO3)3 device shows the best performance, achieving a responsivity of 63.82 mA/W and an external quantum efficiency of 31%, about four times higher than the 30% sample and ∼220 times higher than previously reported GaOOH-based photodetectors.
Khanh, N., Do, H.-B., Nguyen, T.-H., Ngo, T.-H.-L., Phan-Gia, A.-V., Tran, T.T.V., De Souza, M.M., Le, H.-M., Linh, L., Nawaz, M.H., Chuang, F.-C., Pham, P.V. and Nguyen Dang, N. (2026) ACS Applied Electronic Materials, 8(9), pp. 4336–4342.