n-ZnO nanorod/p-si hetrojunction diode is synthesized using a simple chemical solution method on p-type silicon substrates for light emitting diode applications. The grown ZnO nanorods showed highly textured hexagonal crystallographic phase along c-axis. An intense band to band photoluminescence peak is observed at 377 nm in conjunction with the weak deep-level emissions in visible region centred at 500 nm. The current–voltage measurements show diode-like characteristics. The work will also discuss the emission response with bias field for these solution processed n-ZnO/p-Si heterostructures under dark and UV conditions in the context of possible UV photo-response and light emitting diode applications. © Springer Nature Switzerland AG 2019.