Studies of Graphdiyne-ZnO Nanocomposite Material and Application in Polymer Solar Cells

Graphdiyne-ZnO (GDZO) composite material is prepared via a simple method and studied in detail for the first time. The transmission electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) analyses confirm the formation of an adduct between GD and ZnO. Then the interaction between ZnO and GD is further investigated by first-principles calculations. It is found that the Zn and O atom can coordinate bonding with GD, thus forming the C-Zn bond and C-O bond, respectively. Polymer solar cells are fabricated based on the nanocomposites for the first time and an enhanced power conversion efficiency of 11.2%, compared with the devices with ZnO-only (10%), is obtained. Simultaneously, the resultant devices show better stability, whether in glove box or in atmosphere, with humidity of 90%. The investigation of exciton generation rate, ideal current-voltage model, and impedance spectra verify that the introduction of GDZO not only accelerates electron transfer but also reduces charge recombination occurring at the interface. The results indicate that GDZO is a promising electron transport material to enhance solar cell performance and presents a large potential for optoelectronic applications as well.