Fabrication of electrospun polymer nanofibers modified with all-inorganic perovskite nanocrystals for flexible optoelectronic devices

• Published in: Applied nanoscience Vol. 12; no. 10; pp. 2961 - 2977
• Main Authors: Bkkar, Muhammad Ahmad, Olekhnovich, Roman Olegovich, Kremleva, Arina Valerievna, Kovach, Yakov Nikolaevich, Kalanchina, Victoria, Uspenskaya, Mayya Valerievna
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.10.2022; Springer Nature B.V
• Subjects: Annealing; Cesium; Chemistry and Materials Science; Electrical resistivity; Electromagnetic absorption; Electrospinning; Feed rate; Grain size; Materials Science; Membrane Biology; Nanochemistry; Nanocrystals; Nanofibers; Nanomaterials; Nanotechnology; Nanotechnology and Microengineering; Nucleation; Optoelectronic devices; Original Article; Perovskites; Photoluminescence; Polymers; Polyvinylpyrrolidone; Prepolymers; Surface tension; Perovskite; Complexation; Polymer; Stability; Crystallinity; Nanofibers
• ISSN: 2190-5509; 2190-5517
• DOI: 10.1007/s13204-022-02603-6

Polymer–perovskite nanofibers are considered promising active nanomaterials for flexible optoelectronic devices. Herein, polyvinylpyrrolidone (PVP) nanofibers modified with black-phase cesium lead iodide (CsPbI 3 ) nanocrystals (NCs) have been prepared by a one-stage electrospinning method followed by an annealing process. The average diameter of drop-free nanofibers has been varied in the range of 81–579 nm by manipulating the concentration of the entire material from 47.39% to 41.39%; the concentration of perovskite from 33.33% to 46.67%; the concentration of PVP from 7.5% to 15%; the needle diameter from 0.42 mm to 0.72 mm; the feed rate from 0.1 ml/h to 0.3 ml/h; the electrical voltage from 17 to 23 kV; and the working distance from 120 to 150 mm. The correlation between properties of solutions (viscosity of 87–2949 mPa s, electrical conductivity of 5.41–8.44 mS/cm, and surface tension of 38.98–42.66 mN/m) and the average diameter has been described. Stable NCs embedded in PVP nanofibers are obtained after 5 min of annealing at 150–200 °C. Light absorption and photoluminescence (PL) properties improve with an increase in the annealing temperature from 150 °C to 200 °C due to the growth in grain size. The optical bandgap has been found to be ~ 1.77 eV and 1.74 eV at 150 °C and 200 °C, respectively. The formation mechanism of stable NCs has been presented. The low annealing temperature can be explained by the formation of ionic clusters and the aggregation of perovskite precursors around the polymer chains in the intermediate phase, promoting the non-classical nucleation. The stability at room conditions is attributed to the small size of crystals and their complexation with PVP, which allows the fabrication of stable nanofibers for 15 days.