Spin coating was used to prepare TiO2/Si heterojunction photo-detector using anatase TiO2 nanoparticles modified with 1,4-butanediol. The heterojunction was formed between the spin coated TiO2 nanoparticle films (200 nm) and the Si substrates. The heterojuncted structures will facilitate the separation of photogenerated carriers. The large surface-to-volume ratio of TiO2 nanoparticles will improve the lifetime of photo-generated carriers. Our results show that the photocurrent has a linear relationship to the intensity of UV/visible light when negatively biased at -2 V. The quantum efficiency can reach 137% and 190% at 350 nm and 550 nm, respectively. The response/recovery time is very short (t(r) and t(d) <0.05 s), which promising a potential use in rapid detection and multi-band imaging. (c) 2017 Elsevier B.V. All rights reserved.