Research progress on p-type ZnO synthesized by solution method

ZnO is a II-VI group semiconductor material with the wide direct band gap, and is expected to be widely used in the optical display, optical storage, photoelectric conversion, ultraviolet detection and other fields. However, how to achieve a stable p-type ZnO is one of challenges for its application and development. Among the existing methods for the preparation of the p-type ZnO, a solution method has its own advantages such as low cost, simple operation and environment-friendly although there are a few reports about p-type ZnO prepared by the solution method. The paper reviews the development of the p-type ZnO synthesized by the solution method (i.e., non-doping, I group elements doping, V group elements doping, donor-acceptor co-doping) and optoelectronic devices research. The advantages and disadvantages of the p-type ZnO synthesized by the solution method were discussed.