Contacts:
Brian Seger, Department of Physics, CINF-DTU, 4525-3113 (brse@fysik.dtu.dk)
Peter Vesborg, Department of Physics, CINF-DTU, 4525-3113 (vesborg@fysik.dtu.dk)
Official supervisor: Ib Chorkendorff, Department of Physics, CINF-DTU, 4525-3170 (ibchork@fysik.dtu.dk)
Figure 1: a) Diagram of a typical perovskite solar cell. b) Solar cell efficiencies of different types of materials as a function of time. Efficiency graph taken from Hodes, Science, 2013, Vol. 342, pg. 317-318
Perovskite solar cells consisting of H2NCH3NH3PbX3 (X= halide) have been arguably the greatest solar cell breakthrough in the last couple of decades. 6 years ago they had an efficiency of 3% and now (2015) the record efficiency is 20%. Furthermore they are cheap and need relatively simple methods to create them. Figure 1 shows their general design as well as how their efficiencies has improved over time.
Currently the majority of this research is for the purposes of making a single solar cell material. However another approach is to use the perovskite solar cell in combination with a silicon solar cell to form a 2-photon cell. The general concept is that the perovskite will absorb all the high energy photons and leave the low energy photons to be used for the Si. By splitting the solar spectrum between 2 photoabsorbers, we can better utilize the sunlight, and thus greatly increase our solar cell efficiency.
In this project you will look to create perovskite based solar cells that are efficient at absorbing high energy photons for use in a 2-photon device. Wet chemical techniques (spin coating, dropcasting, etc.) will primarily be used to produce the perovskite solar cells. You will use UV-Vis spectroscopy to analyze light absorption properties. The devices will then be characterized by illuminating the samples and measuring voltage vs. current graphs. Maximum power points will be found to determine cell efficiencies.