Morphological and photophysical study in hybrid ternary organic nanoparticles blends

• Published in: Chemical physics 2019-09, Vol.525, p.110388, Article 110388
• Main Authors: Raghav, Anubhav, Kumar Chini, Mrinmoy, Bheemaraju, Amarnath, Paul, Rajashik, Satapathi, Soumitra
• Format: Article
• Language: English
• ISSN: 0301-0104
• DOI: 10.1016/j.chemphys.2019.05.015

[Display omitted] •Organic small molecules based ternary heterotriad with different morphological features are fabricated.•Steady state and time resolved spectroscopy reveals interesting photophysics about these nanostructures.•The morphological and photophysical studies confirm that intratriad nanostructure (nano equivalent of bulk heterojunction morphology) is better than intertriad nanostructure (nano equivalent of bulk mixed trilayer geometry) in terms of its performance characteristics needed to make organic nano optolectronics devices. The electron donor-acceptor based hybrid ternary nanostructures remains a frontier area of research in designing novel light harvesting devices. Here we report the morphological and photophysical study in Intra-triad and Inter-triad nanoparticles by using electron donating donor-acceptor-donor (D-A-D) type Diketopyrrolopyrrole (DPP) molecule which imparts the advantages of both polymers and small molecules and non fullerene electron acceptor, Naphthalene diimide (NDI) and fullerene based acceptor, Phenyl-C61-butyric acid methyl ester (PCBM). Both these nanostructures were fabricated by modified mini-emulsion technique. The Intra-triad nanostructure contains DPP, NDI and PCBM molecules inside the same matrix and in case of Inter-triad nanostructure, individual nanoparticles are attached together by electrostatic force. The morphological optimizations in hybrid nanostructures are performed with the help of AFM studies. We have further studied the structure mediated charge transfer phenomena and lifetime decay profiles by time resolved photoluminescence and steady state spectroscopy measurements. Due to the favorable energy levels, DPP molecules have been employed here as donor molecule for cascade energy transfer in ternary heterotriad geometric system. We have further studied the structure mediated charge transfer phenomena and lifetime decay profiles by time resolved photoluminescence and steady state spectroscopy measurements. Due to the favorable energy levels, DPP molecules have been employed here as donor molecule for cascade energy transfer in ternary heterotriad geometric system. The steady state and time resolved spectroscopy reveal interesting photophysics about the ternary heterostructures. The Intra-triad system has shown improved charge transfer properties compared to Inter-triad system and could be a futuristic material for opto-electronic applications.