Photoluminescence and photocatalytic properties of rhombohedral CuGaO2 nanoplates.

Linlin Shi,Bin Zhao,Dongxu Zhao,Dezhen Shen,Yunpeng Wang,Fei Wang,Dengkui Wang,Ligong Zhang

doi:10.1038/srep21135

Abstract

Rhombohedral phase CuGaO2 nanoplates with a diameter of about 10 μm were synthesized via low temperature hydrothermal method. Room temperature and low temperature photoluminescence of the obtained CuGaO2 nanoplates were characterized. CuGaO2 nanoplates exhibited blue emission at room temperature and free exciton emission were appeared at low temperature. The blue emission is originated from defects such as Cu vacancies, which is the possible origin of p-type conductivity. The appearance of free exciton emission can demonstrate the direct bandgap transition behavior of CuGaO2 nanoplates. The as-prepared p-type CuGaO2 nanoplates were further decorated by n-type ZnO nanoparticles via calcination method to fabricate p-n junction nanocomposites. The nanocomposites exhibited enhanced photocatalytic activity which can be ascribed to the effective separation of photogenerated carriers by the internal electrostatic field in the p-n junction region, and the enhanced light absorption properties resulted from sub-bandgap absorption effect of p-n junction. This work has offered a new insight into the design of p-n junction devices using p-type CuGaO2 nanoplates.

Highlights

In this work, CuGaO2 nanoplates were obtained through a simple hydrothermal method[14,15], the obtained CuGaO2 nanoplates showed high crystalline and p-type properties
The blue emission was observed in CuGaO2 nanoplates, and p-type CuGaO2/n-type ZnO nanocomposite heterostructures were realized for applications in photocatalysis
The morphology and structure of CuGaO2 nanoplates were investigated by using the field-emission scanning electron microscopy (FESEM) and the transmission electron microscopy (TEM)

Summary

Introduction

CuGaO2 nanoplates were obtained through a simple hydrothermal method[14,15], the obtained CuGaO2 nanoplates showed high crystalline and p-type properties. P-type properties of CuGaO2 nanoplates were examined by photoluminescence and electrical measurements. The blue emission was observed in CuGaO2 nanoplates, and p-type CuGaO2/n-type ZnO nanocomposite heterostructures were realized for applications in photocatalysis. To fabricate such CuGaO2/ZnO composite photocatalysts, we used a simple calcination reaction method in solution which can increase the contact areas between large size CuGaO2 nanoplates and small size ZnO nanoparticles. This work has offered new insight into the application of CuGaO2 materials and p-n junction based p-type CuGaO2 nanoplates

Methods

Results

Conclusion