Designing New Inverted Colloidal Quantum Dot Solar Cells for Flexible Applications
Team: NanoEnergy Lab
Lead sulfide (PbS) colloidal quantum dots (CQD) are promising materials for solar cell applications due to their solution processibility and bandgap tunability. The performance of CQD solar cells is currently limited by the quality of the hole transport layer (HTL). 2D tungsten diselenide is a promising material to replace the current HTL because it is p-type and is predicted to have ideal energy band alignment with the current absorbing layer. However, previous work in the Thon group has found that spin-casting 2D tungsten diselenide on top of the absorbing layer led to poor film quality, so we set out to optimize the performance of an inverted CQD solar cell. An inverted CQD solar cell enables us to deposit the 2D tungsten diselenide HTL directly onto the glass substrate, which enables a wider range of processing conditions. Here, we present multiple routes to improve the performance of our inverted CQD solar cells to prepare for the incorporation of 2D tungsten diselenide as the HTL.