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通过在低氧分压和真空中热处理ZnO粉末,获得了ZnO荧光粉．ZnO荧光粉有两个发射谱带,分别位于380 nm(紫外)和510 nm(绿色)．紫外谱带对应于ZnO中的激子发射,是一个单中心发光过程;绿色谱带是一个复合发光过程,与ZnO中的本征缺陷相关,如氧空位、锌空位等．实验表明,高密度的激发条件有利于紫外发射,而低氧分压下的热处理有利于提高绿色发射谱带的强度．研究结果还表明,与紫外发射相联系的激子可向与本征缺陷相联系的绿色发光中心传递能量,这种传递可能是通过激子扩散实现的．
The ZnO phosphor was obtained by heat treatment of ZnO powder under partial pressure of oxygen and vacuum. The ZnO phosphor has two emission bands, located at 380 nm (ultraviolet) and 510 nm (green) respectively. The UV band corresponds to exciton emission in ZnO and is a single-center luminescence. The green band is a complex luminescence process that is related to intrinsic defects in ZnO such as oxygen vacancies and zinc vacancies. Experiments show that the high-density excitation conditions are favorable for UV emission, and the heat treatment under low oxygen partial pressure is beneficial to increase the intensity of the green emission band. The results also show that excitons associated with UV emission can transfer energy to green luminescent centers associated with intrinsic defects, possibly through exciton diffusion.