Insights into Atomic Level π‐Electron Modulations in Supramolecular Carbon Nitride Nanoarchitectonics for Sustainable Green Hydrogen Production

• Published in: Advanced energy materials 2024-08, Vol.14 (29), p.n/a
• Main Authors: Panangattu Dharmarajan, Nithinraj, Fawaz, Mohammed, Sathish, CI, Talapaneni, Siddulu Naidu, Ramadass, Kavitha, Sadanandan, Aathira M., Ta, Xuan Minh Chau, Huš, Matej, Perumalsamy, Vibin, Tricoli, Antonio, Likozar, Blaž, Jeon, Chung‐Hwan, Yang, Jae‐Hun, Vinu, Ajayan
• Format: Article
• Language: English
• Subjects: Amorphous materials; Carbon; carbon doping; Carbon nitride; Carrier recombination; Charge efficiency; Charge materials; Charge transfer; Coupling (molecular); Current carriers; Doping; Electron density; Electron paramagnetic resonance; Electronic structure; Fine structure; First principles; Green hydrogen; Hydrogen production; Hydrogen-based energy; Molecular structure; Photocatalysis; Photocatalysts; Photoelectrons; Spectroscopic analysis; Spectrum analysis; supramolecular self‐assembly; Trimesic acid; Water splitting
• ISSN: 1614-6832; 1614-6840
• DOI: 10.1002/aenm.202400686

Carbon nitrides, metal‐free semiconducting materials, have unique molecular structure and semiconducting properties which have inspired researchers to utilize them as photocatalysts for the sustainable production of hydrogen. However, they suffer from a few drawbacks including fast charge‐carrier recombination rate and low charge transfer efficiency owing to their amorphous and less conducting wall structure which remain as significant challenge for achieving breakthrough in photocatalytic water splitting. Herein, the study reports a supramolecular approach of coupling thiourea and trimesic acid for designing highly efficient C‐doped carbon nitride photocatalysts in which the π‐electron density is precisely manipulated. The developed C‐doped carbon nitride demonstrates the fine‐tuned band positions, the mitigated electron–hole recombination, and enhanced conductivity, resulting in the facilitation of significantly enhanced hydrogen generation through the photocatalytic water splitting under the solar‐simulated light. The position and distribution of C‐doping in the carbon nitride framework are characterized by using advanced analytical techniques such as X‐ray photoelectron spectroscopy, near‐edge X‐ray absorption fine structure spectroscopy, and electron paramagnetic resonance spectroscopy together with the first‐principles studies of the electronic structure and energetics of doping. The remarkable increase in photocatalytic hydrogen generation by using developed C‐doped carbon nitride brings one step closer to achieving a green hydrogen economy. Presenting a state‐of‐the‐art supramolecular approach, this research combines thiourea and trimesic acid to design highly efficient C‐doped carbon nitride photocatalysts. In this approach, π‐electron density manipulation is validated through experimental and computational studies. The catalyst demonstrates fine‐tuned band positions, mitigates electron‐hole recombination, and enhances conductivity, facilitating significantly enhanced visible light assisted hydrogen generation.