Si-incorporated ABX₃ perovskites for next-generation solar cells

Area of Science:

• Materials Science
• Solid State Physics
• Renewable Energy

Background:

• Developing lead-free perovskite materials is crucial for sustainable photovoltaic technologies.
• Existing perovskites often contain toxic lead, hindering environmental compatibility.
• There is a need for efficient and non-toxic alternatives for solar energy conversion.

Purpose of the Study:

• To investigate the potential of methylammonium silicon iodide (MASiI3) and methylammonium silicon germanium iodide (MASi-GeI3) as lead-free photoabsorbers.
• To evaluate their structural stability, electronic, optical, and photovoltaic properties using first-principles calculations.
• To assess their viability for next-generation environmentally benign solar cells.

Main Methods:

• First-principles calculations were employed to study the structural, electronic, and optical properties.
• Calculations included formation enthalpy, Goldschmidt tolerance factor, and octahedral factor for structural stability.
• Electronic band structure, density of states, dielectric functions, and absorption coefficients were analyzed.

Main Results:

• MASiI3 and MASi-GeI3 exhibit robust three-dimensional perovskite structures.
• Direct band gaps and low effective carrier masses indicate efficient charge transport and strong absorption.
• Promising theoretical power conversion efficiencies of 19.56% for MASiI3 and 18.03% for MASi-GeI3 were predicted.

Conclusions:

• The studied silicon-based hybrid perovskites are stable and possess favorable electronic and optical properties.
• These lead-free materials demonstrate significant potential for efficient solar energy conversion.
• MASiI3 and MASi-GeI3 are viable candidates for developing next-generation, non-toxic photovoltaic devices.