Advancing the n → π* electron transition of carbon nitride nanotubes for H2photosynthesis

Guigang Zhang,Markus Antonietti,Lina Li,Yubao Zhao,Aleksandr Savateev

doi:10.1039/c7ta03777e

Abstract

Carbon nitride nanotubes with enhanced optical absorption and advanced charge carrier behavior stimulate photocatalytic hydrogen production.

Highlights

The development of efficient visible light photocatalysts, namely being cost-acceptable, environmentally benign, and stable, has long been pursued as the key issue to convert abundant solar energy into storable and sustainable chemical fuels.[1,2,3,4] Conjugated polymers, which are commonly composed of C, N, O, and H, i.e. light non-metal elements, can be optimized by varying the composition, structure and properties of building blocks and are considered by many researchers as the most promising candidates for visible light photocatalytic H2 evolution to meet the future energy demand.[5,6,7,8,9,10,11,12,13,14,15,16]As a prototypical conjugated polymer, melon-based carbon nitride has drawn particular research interest due to its advantages such as suitable HOMO and LUMO positions, robust stability, and accessible fabrication
The band gap energies estimated from the Tauc plot of pure changes from 56 (CN) is calculated to be 2.75 eV (Table S1†), whereas that of CN-OA-x is narrowed from 2.64 to 2.21 eV, supplying sufficient light absorption needed for photocatalytic H2 evolution with blue and green light
Promising carbon nitride nanotubes were synthesized by selfassembly polymerization of oxamide and urea

Summary

Introduction

The development of efficient visible light photocatalysts, namely being cost-acceptable, environmentally benign, and stable, has long been pursued as the key issue to convert abundant solar energy into storable and sustainable chemical fuels.[1,2,3,4] Conjugated polymers, which are commonly composed of C, N, O, and H, i.e. light non-metal elements, can be optimized by varying the composition, structure and properties of building blocks and are considered by many researchers as the most promising candidates for visible light photocatalytic H2 evolution to meet the future energy demand.[5,6,7,8,9,10,11,12,13,14,15,16]As a prototypical conjugated polymer, melon-based carbon nitride has drawn particular research interest due to its advantages such as suitable HOMO and LUMO positions, robust stability, and accessible fabrication. Similar to most polymers, pristine carbon nitride without modi cation only shows moderate activity due to the insufficient optical absorption and rapid charge carrier recombination.

Results

Conclusion