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

Abstract

As imple method to growaclosely packed carbon nitride (CN) film by the crystallization of CN monomers on ac onductive substrate followed by at hermal condensation is reported. The as-synthesized CN exhibits excellent performance as photoanode material in aphotoelectrochemical cell. Detailed (photo)electrochemical and transient absorption measurements indicate excellent charge separation properties, high hole-extraction efficiency (up to 50 %), al ong electron lifetime,a nd low amount of defect states belowt he CN conduction band. Consequently,t he CN photoanode exhibits am arkedly lowo verpotential of 0.25 Vv ersus reversible hydrogen electrode (RHE), whichiscomparable with the stateof-the-art metal-based photoanodes,a ni mpressive photocurrent density of 116 mAcm À2 at 1.23 Vv ersus RHE in an alkaline solution without sacrificial agent, as well as excellent stability over aw ide pH range (0-13). Figure 1. a) Illustration of the melaminef ilm fabrication.b )Adigital photograph of the melamine film on FTO. c) Top-view SEM image of the melamine film. d) Cross-sectional SEM image of the melamine film. e) XRD patterns of melamine film on FTO and melamine powder. Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

Current understanding and challenges of solar-driven hydrogen generation using polymeric photocatalysts

“…The presence of shallow and deep trap states can also be inferred from different decay kinetics of photoinduced absorptions in the visible and NIR regions 112,[119][120][121] . The presence of trap states can also be inferred from red-shifted electroluminescence compared to the PL of CN x H y thin films 7 and electrons with millisecond lifetimes have been observed in CN x H y photoelectrodes 122,123 . A successful strategy to prevent charge trapping into inactive states has been demonstrated by introducing additional components such as red phosphorous crystals 124 , boron 28 , or TiO 2 mesocrystals 125 , thus enabling rapid charge extraction that effectively competes with charge trapping.…”

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Highly Efficient Polymeric Carbon Nitride Photoanode with Excellent Electron Diffusion Length and Hole Extraction Properties

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