Enhancing Solar Energy Conversion Efficiency: A Tunable Dual-Excitation Dual-Emission Phosphors and Time-Dependent Density Functional Theory Study

The concept of dual-excitation dual-emission (DE2) phosphors for the enhancement of solar energy conversion is introduced in this work. Doping alkaline earth cations as an aggregated energy trap within the sulfur host in a controlled manner resulted in the DE2 phosphors with tunable fluorescent emission properties. It had been found the Ca0.6Sr0.4S:0.005Cu+,0.001Eu2+ phosphor is the optimal DE2 composition. We demonstrated by field testing results their potentials in enhancing sunlight harvesting to increase production of agricultural plants. Time-dependent density functional theory calculations provide insights about their excitation and emission mechanisms. These DE2 phosphors can be applied to a variety of fields, as additives to increase production of agricultural crops, as nanosensor and biolabeling materials for ultrasensitive or green-sensitive detection of biological species such as antibodies, DNA and cells, and other places.