n-doping of organic semiconductors catalysed by organometallic complexes.

Gámez-Valenzuela, Sergio; Li, Jianfeng; Feng, Kui; Liu, Bin; Ma, Suxiang; Li, Yongchun; Lu, Yani; Zhang, Xiage et al. · Nat Commun · 2025

basic_science · Level V

Where this comes from

Abstract

Molecular doping is essential for optimizing carrier concentration, charge mobility, and energy levels of organic semiconductors (OSCs), thereby enhancing device performance. However, efficient n(electron)-type doping remains challenging, as conventional techniques often fail to achieve high doping efficiency with minimal counterion-induced disorder under mild conditions. Here, we present a catalysed n-doping strategy for OSCs using air-stable, cost-effective, and commercially available soluble organometallic complexes, such as Pt(COD)Cl<sub>2</sub>, which enable rapid n-dopant activation with just 10 s of annealing at 120 <sup>o</sup>C. This approach demonstrates excellent generality across diverse OSCs, dopants and catalysts, achieving electrical conductivities exceeding 230 S cm<sup>-1</sup> with up to 10-fold improvements over existing catalyst-assisted n-doping methods. Importantly, it mitigates counterion-induced structural disorder in doped OSCs, leading to a high power factor of 175 µW m<sup>-1</sup> K<sup>-2</sup> and thermoelectric figure of merit (ZT) of 0.43 at room temperature for catalytically N-DMBI-doped polymer films. This strategy addresses long-standing challenges in n-doping while unlocking new avenues for next-generation organic electronics.