Rapid thermal vapor condensation towards crystalline carbon nitride film with improved photoelectrochemical activity

Abstract

Graphitic carbon nitride (g-CN), as an orderly structured polymer derivative, has been widely concerned for its photocatalytic ability due to its metal-free nature and unique properties. However, the photoelectrochemical (PEC) application of g-CN is still hindered by the difficulty of forming high-quality films with good uniformity and crystallinity. Herein, we report the use of a rapid thermal vapor condensation (RTVC) method for growing g-CN films with improved PEC activity. The polycondensation reactions of precursor melamine molecules under the optimized temperature 600 °C and condensation time 20 min resulted in better crystallinity of g-CN films. Remarkably, the growth of g-CN film based on the coalescence of unambiguous hexagonal nanosheets was observed, as corroborated by scanning electron microscopy and transmission electron microscopy. This RTVC method offers a fast and easy strategy for improving the crystallinity of g-CN films through controlling the thermal dynamics and kinetics of film growth from temperature and time.

Recent progress of graphitic carbon nitride films and their application in photoelectrochemical water splitting

“…[89][90][91][92][93] Shortening the thermal vapor deposition time in a preheated furnace (600 °C for 20 min) was found to increase the crystallinity of the CN lms. 94 The photophysical properties of the CN lm can be modulated by changing the monomer composition. 90,93 Giusto et al deposited a CN lm on various substrates by the CVD method, regardless of the shape and surface topology of the substrates.…”