Role of Morphology of Surfactant-Free Nanoparticles in Organic Photovoltaics

• DOI: 10.1007/s11664-020-08144-4
• Publication Date: 2020-04-10T19:02:35Z
• Authors: Darmawati Darwis; Elisa Sesa; Syahrul Ulum; Natalie P. Holmes; Krishna Feron; Mahir Thameel; Riku Chowdhury; Dedy Farhamsah; Levi Tegg; Xiaojing Zhou; Paul C. Dastoor; Warwick J. Belcher
• Keywords: nanoparticle; Sustainable Development Goals; ink stability; precipitation; 01 natural sciences; 7. Clean energy; surfactant-free; 620; 0104 chemical sciences; SDG 7; nanoparticle morphology; organic photovoltaic cells

Nanoparticulate (NP) films and organic photovoltaic devices have been fabricated from poly(3-hexylthiophene):phenyl C61 butyric acid methyl ester (P3HT:PC61BM) NP aqueous dispersions prepared by the precipitation method. The NP inks were stable for more than 4 days, and nanoparticle organic photovoltaic (NP-OPV) devices with efficiency (η) of 1% were fabricated. Detailed analysis of the morphology and performance of the precipitated NP-OPV devices indicated that an optimal blend is responsible for the photocurrent and efficiency observed. These results were confirmed by grazing-incidence x-ray diffraction (GIXRD) analysis, which revealed that the precipitated NPs were resistant to thermal phase segregation, allowing thermal conditioning of the NP films. These results show that precipitated NPs provide a pathway to thermally stable NP-OPV devices with higher photocurrents and efficiencies, approaching those of optimal bulk heterojunction (BHJ) OPV devices.