SBIR Phase II: Quantum Confined Atom Based Nanophosphors for Future Efficient Lighting

这个小型企业创新研究（SBIR）第二阶段项目将涉及将单个原子量子限制在2至5纳米尺寸的三元半导体中，从中开发出新型高效的纳米荧光粉。纳米荧光粉的带隙工程允许在发光特性，如吸收和发射光谱，半宽度，效率，寿命等的改善。事实上，传统的激活剂（稀土和过渡金属杂质）在纳米荧光粉的作用可以重新评估不同的应用。具体地，三元宽带隙半导体如具有掺杂剂如Ag、Cu、Mn的ZnCdS提供非常有效的宽带可见光谱，其接近于白色光。在三元半导体纳米晶体中进行带隙工程的可能性，类似于从III-V族半导体中弹射出光电器件的可能性，为设计与LED和紧凑型荧光灯的激发光谱匹配良好的新型纳米荧光粉打开了大门。这一发展将在第二阶段项目中产生一类新的白色光源。 通过开发可以由蓝色/UV LED激发的不同纳米荧光粉，成功地证明了纳米荧光粉不仅可以显著增强白色LED的性能，而且可以改善紧凑型荧光灯和弧光灯的性能。在商业上，当与电流高效灯一起使用时，纳米荧光粉工程的这一技术突破预计将分别将LED的效率提高40%和灯的效率提高15%。这些灯的整体功率效率的提高将大大降低能源使用成本，预计到2025年将有助于节省相当于250亿美元的能源成本。

This Small Business Innovation Research (SBIR) Phase II project will involve quantum confining a single atom in 2 to 5 nm size nanocrystal of ternary semiconductor, from which new and efficient nanophosphors will be developed. The band-gap engineering of nanophosphors allows improvement in the luminescence characteristics such as absorption and emission spectra, half-width, efficiency, life-time, etc. Indeed the role of conventional activators (rare-earths and transition metal impurities) in nanophosphors can be re-evaluated for different applications. Specifically, ternary wide band gap semiconductors such as ZnCdS with dopants like Ag, Cu, Mn offer very efficient broad-band visible spectra that is close to white light. The possibility of band-gap engineering in nanocrystals of ternary semiconductors, similar to that catapulted the optoelectronic devices from III-V semiconductors, opens the door to design of new nanophosphors that match well with the excitation spectra of LED's and compact fluorescent lamps. This development would lead to a new class of white light sources in this Phase II project. By developing different nanophosphors that can be excited by blue/UV LEDs, it successfully demonstrates that nanophosphors can significantly enhance the performance of not only white LEDs but also can improve the performance of compact fluorescent and arc lamps. Commercially this technological breakthrough of engineering of nanophosphors when used with current efficient lamps, is expected to enhance the efficiency of LED's by 40% and lamps by 15%, respectively. These improvements in overall power efficiency of these lamps, will significantly lower the cost of energy used and it is projected will help to save energy costs equivalent to $25 billion by 2025.