Chalcogenide Perovskites for Efficient, Stable, and non-toxic Solar Cells

Chalcogenide Perovskites (CPs) have an enormous potential for Photovoltaics (PV).

They have a high absorption coefficient and direct, tunable bandgap range of 1.45 - 2.2eV, complementing Si solar cells.

Moreover, CPs are composed of earth-abundant and nontoxic elements and have high thermal stability when exposed to air and humidity.

However, no working CP-based solar cells have been reported due to their very high synthesis temperatures in a sulfur-reach environment.

Realizing the potential of efficient and nontoxic CP-based solar cells currently faces two main challenges: the high synthesis temperature and the lack of control over doping.

The overall goal of my project is to make CPs into photovoltaic absorbers by developing synthetic routes that provide highly crystalline thin films below temperatures of 500 C and controlling their doping levels.To address these two missions, I will use a one-of-a-kind suite of thin-film deposition systems at my host institution (DTU Denmark).

The system is dedicated to high throughput synthesis of sulfides with air-free transfer between three film processing tools.

I will use combinatorial methods to systematically study the effect of changing elemental composition, chemical potentials, and process parameters on the crystallization temperature.

After depositing high-quality thin film at lower temperatures, I will use the unique possibilities to control the charge carriers concentration in the CPs thin films at the host lab by incorporating various extrinsic dopants.The wide use of combinatorial synthesis and high throughput characterization in this research will bring substantial, high-quality data for machine learning (ML) and deep learning (DL) purposes.

Depositing CPs on TCOs can pave the way for a new kind of stable and nontoxic solar cells with moderate production costs.