Preparation of radial ZnSe-CdS nano-heterojunctions through atomic layer deposition method and their optoelectronic applications

Radial 1-D nano-heterojunctions have distinct optoelectronic properties. However, their complex fabrication process is still the bottleneck of device applications. Herein, a facile atomic layer deposition (ALD) method was used to coat a polycrystalline CdS thin film with high uniformity and controllable thickness on the surface of the as-synthesized p-type ZnSe nanowires, for fabricating radial 1-D ZnSe-CdS nano-heterojunctions. The nano-heterojunctions exhibited excellent optoelectronic properties. Under blue/violet light, the nano-heterojunctions obtained a response radio of ∼5 × 10 3 , a responsitivity of ∼1.43 A/W, a gain of ∼3.78 and a detectivity of ∼0.57 × 10 12 cmHz 1/2 W −1  at zero bias. Furthermore, the nano-heterojunction also showed obvious photovoltaic characteristic with a power conversion efficiency of ∼0.96%. This method is expected to play an important role in nano-heterojunction construction and their device applications.