Insights into enhancing photocatalytic reduction of CO2: Substitutional defect strategy of modified g-C3N4 by experimental and theoretical calculation approaches
| Autor: | Nur Umisyuhada Mohd. Nor, Elham Mazalan, Nor Aishah Saidina Amin |
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| Rok vydání: | 2021 |
| Předmět: |
Materials science
Dopant Band gap Mechanical Engineering Doping Metals and Alloys chemistry.chemical_element 02 engineering and technology Electronic structure 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences chemistry Mechanics of Materials Chemical physics Materials Chemistry Photocatalysis Density functional theory 0210 nano-technology Carbon Electrochemical reduction of carbon dioxide |
| Zdroj: | Journal of Alloys and Compounds. 871:159464 |
| ISSN: | 0925-8388 |
| DOI: | 10.1016/j.jallcom.2021.159464 |
| Popis: | The defects in g-C3N4 by material substitution have been proven to enhance photocatalytic reaction. Even so, accurate position substitution of carbon doping for defects in g-C3N4 structure remains a significant challenge. Herein, we investigate the effects of C/doping on the optical and electronic structure of g-C3N4 by combining experiments and density functional theory (DFT). The results reveal that substitution of C atom with N site by 12.7% defect concentration confer efficient separation of electron-hole pairs and photocatalytic activity in comparison with the pristine g-C3N4. The defect constructed at CN1 site position exhibits expanded light absorption edge of g-C3N4, and indicates a small bandgap while maintaining a negative value of CB potential for CO2 reduction to methanol. During performance testing, the highest methanol yield of 651.7 µmol gcat−1 h−1 and AQY = 0.019 with ca. 40% improvement are reported over 0.2C/g-C3N4 compared to pristine g-C3N4. First principle calculations attest the defect position of g-C3N4 structure, introduced by carbon dopant, is beneficial as a tuneable energy band gap that increases light harvesting. This work highlights defect engineering of g-C3N4 structure by carbon doping is a promising way to enhance the performance of photocatalytic carbon dioxide reduction to methanol. |
| Databáze: | OpenAIRE |
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