Preparation,structure And Optical Properties Of Several Glass/glass Ceramics For LCD Backlight Display/fluorescence Pb²⁺ Detecting Applications

With the continuous progress of science and technology,more and more glass ceramic materials have been developed to apply in the field of photoelectricity,which has brought convenience to human beings.In this work,two kinds of novel glass/glass-ceramic materials have been developed for the applications of liquid-crystal display（LCD）and fluorescence Pb²⁺detection as follows,respectively:（1）Nd F₃Glass Ceramic:An Efficient Bandpass Color Filter for wide color gamut LCD backlight displayTo pursue wider color gamut,LED backlight uses narrowband emission Pb/Cd based red/green quantum dots as fluorescent conversion materials,which exist many problems such as high toxicity,poor thermal/chemical stability,complex packaging process and high cost.To this end,the researchers proposed the bandpass filter technique——based on the construction of w LED by"blue light chip+YAG:Ce³⁺+CASN:Eu²⁺",and introduced Nd³⁺for filtering,so that the green light and red light regions in the electric spectrum of white light LED become narrow and separate each other.This technology has significant advantages in cost-effectiveness and is easy to be accepted by industry.Developing bandpass filters with excellent optical properties and stable physicochemical properties is the key to realize this technology. commercial Nd F₃ powder,YAGG:Ce³⁺green powder,CASN:Eu²⁺red powder and Sn-P-F-O low melting temperature glass powder were mingled and sintered via low temperature co-sintering technology.The results show that the glass melting did not impact the microstructure of YAGG:Ce³⁺green powder and CASN:Eu²⁺red powder,while the thermal erosion effect on Nd F₃powder is obvious.Spectral analysis shows the spectral peak shape can be modulated effectively due to the hypersensitive transition absorption of Nd³⁺in the orange-yellow and cyan-blue regions——the green and red emission bands are separated,so the LED color gamut is raised from 70.5%NTSC to74.9%NTSC.（2）Novel lead sensitive borate glass powder and its’application in the fluorescent colorimetric solid phase lead detectionLead detection is essential for protecting the ecological environment and human’s life and health.Conventional Pb²⁺detection technology requires sophisticated instrument and can only be carried out by a trained person in the lab,which is costly,time-consuming and complex to operate.In recent years,with the development of microspectrometer,smart phone and other technologies,fluorescent lead detection technology has begun to attract human attention,which can realize on-site and real-time lead detection.The development of high performance lead-sensitive materials is the key to realize this technology.In this work,we developed a new type of glass doped Eu³⁺lead-sensitive material and corresponding fluorescent colorimetric solid-phase lead detection technology.The Cs Pb Br₃perovskite NCs were precipitated on the surface of glass powder after the material is grinded with the Pb²⁺source.The reaction mechanism is mechanically-drivien glass crystallization.The green emission of Cs Pb Br₃depended on Pb²⁺concentration can be as indicator signal and the red emission of Eu³⁺independed on Pb²⁺concentration can be as reference signal.The Pb²⁺content can be judged qualitatively by the naked eye or quantitatively detected by a fluorescence spectrometer.The LOD of Pb²⁺is 70 ppm with highly selective.Moreover,we have preliminarily verified the feasibility of quantitative/semi-quantitative Pb²⁺detection via CCD cameras of smartphones.