Lead-Free Solar Cells Achieve Breakthrough 33% Efficiency

• Lead-free perovskite solar cells achieve 33.68% efficiency, showcasing groundbreaking potential in sustainable energy with optimized material design and temperature resilience.

Researchers from India, Japan, and Taiwan have analyzed a lead-free perovskite solar cell design with a structure of FTO/TiO2-SnO2/CsSnCl3/Cu2O/Au, achieving a power conversion efficiency of 33.68%. The study focused on optimizing the thickness and doping of the electron transport surface (TiO2-SnO2), light-absorbing layer (CsSnCl3), and hole transport surface (Cu2O), with the optimized thicknesses being 0.2, 1.8, and 0.02 μm, respectively.

The device demonstrated an open circuit voltage of 1.46 V, short circuit current density of 27.53 mA/cm², and a fill factor of 83.58%. It also showed strong temperature resilience between 290-310 K. This research underscores the potential of lead-free perovskites in advancing solar cell technology through strategic material selection and optimization.

How does the new lead-free perovskite solar cell achieve 33.68% efficiency?

• Utilization of a lead-free perovskite material, CsSnCl3, which offers a suitable bandgap for efficient light absorption.
• Optimization of the electron transport layer (TiO2-SnO2) to enhance electron mobility and reduce recombination losses.
• Precise control of the thickness of each layer to maximize light absorption and charge carrier transport.
• Doping strategies to improve the conductivity and charge carrier mobility in the electron and hole transport layers.
• Use of Cu2O as a hole transport layer, which provides good energy level alignment and efficient hole extraction.
• High open circuit voltage achieved through effective energy level alignment and reduced recombination.
• Strong temperature resilience, maintaining performance across a range of operating temperatures.
• High fill factor indicating low series resistance and efficient charge extraction.
• Strategic material selection to avoid toxic lead, making the solar cells more environmentally friendly.