Novel method proposed to design high-efficiency guest components for ternary organic solar cells

A analysis group led by Prof. Ge Ziyi on the Ningbo Institute of Supplies Expertise and Engineering of the Chinese language Academy of Sciences has proposed a key technique for optimizing visitor parts to attenuate non-radiative voltage losses and thus obtain high-efficiency ternary natural photo voltaic cells (OSCs).

This work was published in Superior Supplies.

OSCs have attracted appreciable consideration within the discipline of natural digital gadgets resulting from their gentle weight, good mechanical flexibility and transparency. The ternary technique, by which a visitor component is launched into a bunch binary systemis taken into account to be one of the vital efficient and facile methods to attain OSCs with glorious energy conversion efficiencies (PCEs).

Numerous environment friendly visitor parts have been developed for binary host programs, however there’s nonetheless no efficient method to predict the effectiveness of visitor parts in bettering gadget effectivity.

Utilizing density useful idea calculations, the researchers designed and synthesized three asymmetrical non-fullerene acceptors (ANFs) with totally different electrostatic potential (ESP) distributions, specifically ANF-1, ANF-2, and ANF-3.

These three ANFs have been used as visitor acceptors within the well-known host system of D18:N3. Then the consequences of the introduction of the visitor part on the photovoltaic properties have been rigorously investigated.

The experimental outcomes confirmed that a big ESP distinction between the visitor acceptor and the host system results in robust intermolecular interactions and a excessive miscibility of the 2 molecules, which improves the luminescent effectivity of the mix movie and the electroluminescence quantum yield (EQE_HE) of the gadget, thus decreasing the voltage lack of ternary OSCs.

In contrast with ANF-1 and ANF-2-based ternary movies, the ANF-3-based ternary movie exhibited a bigger ESP distinction between the visitor acceptor and the host acceptor, thus exhibiting increased and extra balanced mobility, and smaller part separation dimension, contributing to a more practical cost transport.

Because of this, the D18:N3:ANF-3 ternary OSC achieved the best PCE of 18.93% with a low voltage lack of 0.236 eV.

This work gives an necessary guideline for designing high-efficiency visitor acceptors to additional enhance the open-circuit voltage within the ternary OSCs: enhance the ESP distinction between the visitor acceptor and the host acceptor.

Moreover, this rule has been verified in different reported high-efficiency ternary OSCs, demonstrating its glorious generality.

This research could make clear the design and improvement of single-junction OSCs with PCE above 20%.