Amine-Based Interfacial Engineering in Solution-Processed Organic and Perovskite Solar Cells

Area of Science:

• Materials Science
• Energy Science
• Photovoltaics

Background:

• Organic solar cells (OSCs) and hybrid perovskite solar cells (PvSCs) require optimized interfaces for efficient electron extraction and reduced recombination.
• Transparent electrodes with low work functions are crucial for improving performance in these devices.
• Interfacial modifiers play a key role in achieving suitable energy-level alignment and charge carrier selectivity.

Purpose of the Study:

• To investigate amine-based interfacial modifiers (ABIMs) for enhancing electron transport in OSCs and PvSCs.
• To perform energy-level mapping between transparent electrodes and photoactive layers using ABIMs.
• To improve the power conversion efficiencies (PCEs) of solution-processed solar cells.

Main Methods:

• Synthesis and application of amine-based interfacial modifiers (ABIMs), specifically polyethylenimine ethoxylated (PEIE).
• Fabrication of inverted OSCs and planar n-i-p PvSCs incorporating PEIE.
• Characterization of energy-level alignment and device performance, including power conversion efficiencies (PCEs).

Main Results:

• PEIE incorporation in inverted OSCs dramatically increased PCE from 0.32% to 9.83% due to enhanced interfacial dipole moments and energy-level alignment.
• PEIE demonstrated versatility across different photoactive layers, including fullerene derivatives and nonfullerene acceptors.
• Inverted nonfullerene OSCs and planar n-i-p PvSCs with PEIE achieved outstanding PCEs of 11.88% and 17.15%, respectively.

Conclusions:

• Amine-based interfacial modifiers, particularly PEIE, are highly effective in optimizing interfacial energy levels for improved electron transport in OSCs and PvSCs.
• PEIE offers a versatile solution for boosting the performance of various types of solution-processed solar cells.
• The study highlights the significant potential of PEIE for advancing the efficiency of next-generation photovoltaic technologies.