High Efficiency Inverted Planar Perovskite Solar Cells with Solution-Processed NiO_x Hole Contact

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Nickel oxide (NiO_x) is a viable hole-transporting material for perovskite solar cells (PSCs).
• Its high hole mobility, stability, and processability make it attractive for PSC applications.

Purpose of the Study:

• To optimize NiO_x films as hole-transporting layers in PSCs.
• To investigate the effect of perovskite layer thickness on device performance.
• To achieve high power conversion efficiency (PCE) in PSCs using solution-processed NiO_x.

Main Methods:

• Fabrication of PSCs using solution-processed NiO_x as the hole-transporting layer.
• Systematic variation of perovskite layer thickness and precursor concentration.
• Optimization of NiO_x and PCBM electron selective layer thicknesses.
• Characterization using UV-vis, photoluminescence, and electrochemical impedance spectroscopy.

Main Results:

• An optimal perovskite thickness of 334.2 nm was identified at a precursor concentration of 1.35 M.
• Optimized device fabrication yielded a best PCE of 15.71% with a J_sc of 20.51 mA·cm^-2, V_oc of 988 mV, and FF of 77.51%.
• The optimized PSC exhibited stable efficiency of 15.10% and minimal hysteresis.

Conclusions:

• Solution-processed NiO_x is a highly effective hole-transporting material for high-efficiency PSCs.
• Thickness optimization of both perovskite and NiO_x layers is crucial for maximizing device performance.
• This approach offers a promising pathway for developing efficient and stable inorganic hole-transporting material-based PSCs.