Wageningen University & Research: Method to stabilise promising material for cheaper next-gen solar cells

Halide perovskites are a promising candidate for the next generation of clean-energy producing photovoltaic (PV) technologies. Technologies that converse electricity into light. Halide perovskites are low in cost, have facile fabrication and outstanding semiconductor properties. However, the efficiency of photovoltaic devices made by perovskites are still below practical limits and partial long-term stability hinder their practical application.

Nanoscale performance
Dr. Ruggeri from Wageningen University & Research, within the Chairs of Organic Chemistry and Physical Chemistry, in collaboration with Dr. Sam Stranks at the University of Cambridge, has contributed to understand how halide organic cations aka positively-charged ions, such as methylammonium (MA) and formamidinium (FA), affects the performances of perovskites materials at the nanoscale. While at the macroscopic scale these materials appear stable, a heterogeneous distribution of the organic cations at the microscopic scale causes instability. This limitation in performances can only be characterised by nanoscale approaches.

Advanced Chemical Analysis
In particular, in this study, Dr. Ruggeri has applied an advanced technique called infrared nanospectroscopy (AFM-IR) to map within a thin layer of perovskite material, down to 10 nm spatial resolution, the chemical distribution of the organic cations of FA and MA that fundamentally modify and affect the performances of this promising materials. Overall, the contribution of Dr. Ruggeri and Wageningen University & Research, paves the way for the future and more in detail nanoscale chemical characterisation of perovskites and new materials for clean-energy production.

New Materials for Energy Harvesting
Finally, the scientists in Cambridge have engineered a new class of FA- and MA-free perovskites, based on surface-bound ethylenediaminetetraacetic acid, that was extremely stable against thermal, environmental, and light stressors.