Enhanced Capture of Broadband Solar-Blind UV Light via Introducing Alkali-Metal Ions (Li+, Na+, and K+) into DC Spectral Converter

作者：Jia, Hong; Li, Xue^*; An, Ximei; Chang, Shasha; Liu, Zhongli; Peng, Feng; Liu, Xiaofeng; Gao, Linhui; Zhou, Shifeng^*; Qiu, Jianrong

来源：Advanced Optical Materials, 2021, 9(6): 2001703.

DOI：10.1002/adom.202001703

• down&#8208
• conversion spectral converter
• organic&#8211
• inorganic composite films
• solar&#8208
• blind ultraviolet detection
• Y2O3
• Eu3+ phosphors

Rare earth doped down-conversion (DC) materials, due to their unique spectral conversion characteristics, are promising candidates for narrow band solar-blind ultraviolet (UV) light detection devices. Herein, an enhanced capture device for broadband solar-blind UV light is constructed by combining an ordinary semiconductor with a DC spectrum converter, the essence of which is to introduce the appropriate alkali-metal ions (Li+, Na+, and K+) into DC layer. Europium-doped organic-inorganic composite films are used as spectral converters because of their excellent DC characteristic, which can convert broadband solar-blind UV incident illumination into visible light suitable for capture by light dependent resistor (LDR). Interestingly, the spectral conversion efficiency is positively correlated with the capture ability of broadband solar-blind UV photons. The introduction of alkali-metal ions in the DC layer enhances the photon detection efficiency with an increase rate of around 200%, which is attributed to alkali-metal ions changing the local crystal field symmetry around the Eu3+ emitter and distorting the matrix crystal of Y2O3, thus increasing the probability of intra-4f electron transition. These results signify that the present rare-earth doped DC luminescent materials are promising building blocks for assembly of high-performance broadband solar-blind UV detector.

• 单位
  Zhejiang University