Synthetic Route of CdSe Nanocrystalline Films Fabricated by Substrate Vibration Assisted Drop Casting Method

Herein, we report a greener, non-toxic, cost effective and a modest scheme for the fabrication of excellent CdSe nanocrystals (NCs). Precursors for the present reaction are synthesized by the treatment of cadmium chloride (CdCl2) with 2-pyridyl selenolate (NaSeC5H4N) resulting a complex of the formula [(C5H4NSe)2Cd]. The complex is characterized by NMR (1H and 13C) and IR spectroscopies. The complex, [(C5H4NSe)2Cd] is found to be polymeric in nature, as indicated by its insolubility in solvents, and is further customized as a single-source pioneers for the preparation of colloidal CdSe NCs. Thermolysis of [(C5H4NSe)2 Cd] has been successfully carried out by hotinjection method using low-cost and harmless oleic acid (OA) as the coordinating solvent, thereby rejecting the need of air-sensitive and toxic solvents. Based upon dynamic light scattering (DLS) technique, the average size of colloidal CdSe NCs are determined using particle size analyzer. The average size of colloidal NCs comes out to be 6.3 nm. Thin films of colloidal CdSe NCs are deposited on glass substrate using drop-casting (DC) and ultrasonic substrate vibration assisted drop casting (SVADC) methods to study their use as workable materials for engineering devices. The films are characterized by ultraviolet-visible spectroscopy (UV-vis), photoluminescence (PL) studies, X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques.

Grain engineering by ultrasonic substrate vibration post-treatment of wet perovskite films for annealing-free, high performance, and stable perovskite solar cells

The ultrasonic substrate vibration post-treatment (SVPT) of wet perovskite films can eliminate the annealing process.