Carbon Sensitized Energy Converters
Half the Sun’s power lies in the infrared (IR) beyond 700 nm and more than one third lies beyond 1000 nm. Higher solar cell efficiencies, of over 40%, are thus attainable when supplementing visible harvesting solar cells with multiple junctions having optimally chosen IR bandgaps beyond 1200 nm.
Of all the solution processed materials available, only PbS colloidal quantum dots (CQDs) and semiconducting carbon nanotube are able to absorb sunlight within the 1000 nm to 2000 nm spectral band. The major challenge in infrared active junctions utilizing CNTs or PbS CQDs is the limited diffusion limit of the carriers: thicker junctions are dominated by recombination losses due to the inability to extract photocarriers from deeper in the bulk region. This is a critical problem in the research that is pervasive throughout the general class of solution-processed nanomaterials.
Our primary objective in this direction is to study the interfacial design and carrier dynamics of the IR junctions as well as exploring advanced single junction hybrid quantum dots/CNT architectures to enhance extraction efficiency. This includes experimental as well as computational component analyzing the carrier exchange between the sorting polymers, quantum dots and CNTs to engineer efficient energy converters with synergetic hybridized systems.