Transparent Conducting Oxide Nanocrystals: Synthesis, Challenges, and Future Prospects for Optoelectronic Devices

Flexible transparent electrodes are prerequisites of next-generation electronic devices. Most of the synthesis process of conventional transparent conducting oxides (TCOs) require high vacuum and high temperature, which hinder its application in flexible devices. Colloidal TCO nanocrystals (NCs) can be potential candidates in this regard. But till date, the electrical performances are not promising for commercial applications. Therefore, a detailed understanding of synthesis, electrical transport, and challenges is required for further development of colloidal NC-based transparent electrode. Herein, notable works with emphasis on synthesis, postsynthesis modification, along with film deposition techniques are summarized. The comparative studies of electrical performance of promising TCO materials with its thin-film counterpart are presented to draw future prospects of TCO NCs as commercial transparent electrodes.