Physical vapor deposition of graphitic carbon nitride (g-C3N4) films on biomass substrate: optoelectronic performance evaluation and life cycle assessment

Physical vapor deposition (PVD) is a simple and fast method for preparing uniform graphitic carbon nitride (g-CN) films. However, current vapor deposition methods require temperatures above 500 °C, which greatly limits the application of biomass substrates. Here, a facile low-temperature PVD technology for the deposition of g-CN films on biomass substrates is reported. The method was applied using conductive wood as the substrate, and the resulting samples were comprehensively characterized and compared with conventional g-CN films on indium tin oxide (ITO) glass. Photoelectrochemical experiments showed that the g-CN film has the same light response performance on conductive wood as on ITO glass, while life cycle assessment showed that the biomass substrate has a much smaller environmental impact than ITO glass. The results from this study are expected to pave the way for the widespread application of biomass-based materials in the field of semiconductor optoelectronics.Graphical abstractA low-temperature PVD technology for deposition of g-CN film on high-temperature intolerant biomass substrates and its life cycle assessment