Control of electrical and optoelectronic properties via defined crystallisation from solution

Supervised by Markus Antonietti, Dieter Neher and Marcus Bär

 

In the last years, the rapid progress in prevoskites (ABX3) solar cells truly makes these materials as a strong candidate for the replacement of other first generation inorganics within commercial light harvesting devices. The most efficient metal halide perovskites solar cells are composed on base of the very toxic Lead (Pb) as the metal center. Although there were several studies to replace the toxic metal with safe metals (Sn and Cs), the solar cell efficiency and stability was strongly decreased. Beside the absorber in the cell, also the electron acceptor layer and the mesoporous scaffold appear to be important in the charge separation process and in the enhancement of the solar cell performance.

 

The aim of the PhD thesis is to synthesis new types of perovskites with different metal centers and alternative organic ligands. Beside synthesis of composition, especially nanostructure and superparticle architecture are subject to synthesis. The careful design of the synthesis will allow us to control the photophysical and the chemical properties of the material. In addition, we aim to replace the electrons acceptor layer and the mesoporous scaffold with carbon nitride-like materials. The use of modified carbon nitrides can lead to the increase of the solar cell parameters due to the possibly to carefully design electrons cascade via heterojuction formation within the carbon nitride-like materials. Moreover, the optical properties (energy levels position along with the absorption spectra) of the carbon nitride materials can be easily tuned and might lead to higher performance of the solar cell via photovoltage and photocurrent enhancement.