Thin Film Tandem Solar Cells

Tandem solar cells combine multiple photovoltaic junctions to produce greater power output from applications with a limited area.
Current tandem technology is centred around crystalline silicon meaning modules produced are rigid modules.
Project will develop new low <0.9eV bandgap solar cell materials to act as tandem partner layers to industrially established CdTe or emerging Sb2Se3 solar cells.
This will enable development of novel all thin-film tandem solar cells capable of being directly integrated into glass facades, producing higher power densities for applications such as building integrated photovoltaics (BIPV) or automotive photovoltaics.
Project will initially focus on development of Sb2(SexTe1-x)3 anisotropic semiconductor material with tuneable bandgap dependent on the Se/Te ratio.
Efficacy of low band gap solar cells will be demonstrated in isolation before formation of CdTe/ Sb2(SexTe1-x)3 tandem test cells using established CdTe process in SIRE.
Student will develop skills in numerous thin film fabrication techniques; RF/DC sputtering, close space sublimation, thermal evaporation and solution processing.
Student will become an expert in solar cell production and device level performance analysis as well as underlying materials characterisation with a particular focus on defects and interfaces.
The key aims of the project will be i) identify appropriate fabrication route for low bandgap Sb2(SexTe1-x)3, ii) demonstrate single junction solar cell based on novel Sb2(SexTe1-x)3 absorber, iii) produce test all thin film tandem solar cell, iv) identify performance limitations and routes to improve performance.

Project will take place in the University of Liverpool’s Stephenson Institute for Renewable Energy (SIRE) a multidisciplinary research centre focussed on renewable energy.

SIRE PV lab has established world class solar cell fabrication and characterisation facilities in which the project will be run

Student will become part of the PV devices research team and link with ongoing research in SIRE focussing on PV materials and devices working closely with other students focussed on solar cell fabrication.