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Updated: Apr 21, 2026
08:12
Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
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Shifting Defect Self-Regulation via Disordered Vacancies in Hollow Tin Perovskites
Autumn N Peters1, Persephone A Jordano1, Jennifer A Taylor1
1Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States.
Chemistry of Materials : a Publication of the American Chemical Society
|April 20, 2026
Summary
Researchers minimized self-doping in tin halide perovskites by substituting ethylenediammonium for methylammonium cations. This strategy enhances control over carrier density and mobility, advancing dopable hybrid semiconductor development.
Area of Science:
- Materials Science
- Solid-State Chemistry
Background:
- Tin-(II)-based hybrid halide perovskites exhibit self-doping due to Sn-(II) oxidation to Sn-(IV).
- This leads to high carrier densities and metallic conductivity, limiting their applications.
Purpose of the Study:
- To minimize self-doping in tin halide perovskites.
- To explore the effect of ethylenediammonium substitution on perovskite properties.
- To establish a defect-driven control strategy for carrier concentration.
Main Methods:
- Solvent-free mechanochemical synthesis of MA1-x en x Sn1-0.7x I3-0.4x perovskites.
- Characterization using dark and time-resolved microwave conductivity measurements.
- Analysis of composition and defect chemistry as a function of ethylenediammonium (en) substitution.
Main Results:
- Substitution of ethylenediammonium (en) effectively minimized intrinsic self-doping.
- Two conductivity suppression regimes were observed based on 'x' (en incorporation).
- Carrier density decreased by an order of magnitude at low 'x' via defect-mediated compensation; carrier mobility was reduced at higher 'x'.
Conclusions:
- Ethylenediammonium substitution offers a strategy to control carrier concentration in tin halide perovskites.
- Mechanochemical synthesis circumvents oxidative side reactions, enabling precise control.
- Findings advance the rational discovery of dopable hybrid semiconductors.
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