A Water-Splitting Carbon Nitride Photoelectrochemical Cell with Efficient Charge Separation and Remarkably Low Onset Potential

"This is the peer reviewed version of the following article: Peng, Guiming, Josep Albero, Hermenegildo Garcia, and Menny Shalom. 2018. A Water-Splitting Carbon Nitride Photoelectrochemical Cell with Efficient Charge Separation and Remarkably Low Onset Potential. Angewandte Chemie International Edition 57 (48). Wiley: 15807 11. doi:10.1002/anie.201810225, which has been published in final form at https://doi.org/10.1002/anie.201810225. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving."
[EN] A simple method to grow a closely packed carbon nitride (CN) film by the crystallization of CN monomers on a conductive substrate followed by a thermal condensation is reported. The as-synthesized CN exhibits excellent performance as photoanode material in a photoelectrochemical Detailed (photo)electrochemical and transient absorption measurements indicate excellent charge separation properties, high hole-extraction efficiency (up to 50%), a long electron lifetime, and low amount of defect slates below the CN conduction band. Consequently, the CN photoanode exhibits a markedly low overpotential of 0.25 V versus reversible hydrogen electrode (RHE), which is comparable with the state-of-the-art metal-based photoanodes, an impressive photocurrent density of 116 mu A cm(-2) at 1.23 V versus RHE in an alkaline solution without sacrificial agent, as well as excellent stability over a wide pH range (0-13).