Grant: Research Tools and Instruments - Category 1 (<$150,000)

Consumers and industry are seeking safe, durable, energy-efficient alternatives to traditional incandescent light bulbs. Although compact fluorescent lamps (CFLs) are comparatively efficient, they contain mercury, which requires special handling for disposal and in the case of bulb breakage. Light emitting diodes (LEDs) are a safer, more efficient and longer lasting alternative to CFLs. However, manufacturing efficient white LEDs is complicated and expensive. The fabrication of quasi-white LEDs is currently based on combining LEDs of different colours, or using a mixture of different phosphors (often containing expensive rare-earth elements). We designed and prepared low-cost high-efficiency organic-nanocrystal hybrid material whose illumination can tuned to any colour in the visible range, including pure white light, and which can be processed into light emitting structures and devices from liquid (i.e. solution) or solid (i.e. powder). The obtained hybrid nanomaterial acts as a single illumination entity, rather than a mixture, and provides a homogeneous and uniform white light emission. Understanding the electronic coupling mechanism of nanocrystals and molecular adsorbates is the key to controlling the photophysical properties of this type of hybrid materials and the optimization of their efficiency and performance. Time-resolved photoluminescence measurements are an indispensable tool for studying the dynamics of charge and energy transfer processes.The requested equipment for time-dependent photoluminescence measurements will enable us to directly probe charge and energy transfer processes with high temporal resolution. In conjunction with other spectroscopic studies the obtained results will help understand the properties of nanocrystal surface-bound molecules and the electronic interactions between the molecular adsorbates and colloidal nanocrystals. The obtained results are expected to lead to a rational design of new energy-efficient illumination sources. Commercialization of this technology will help promote Canada as a leader in energy-efficient technologies and provide the training and employment opportunities for HQP.