Combined DFT-D3 Computational and Experimental Studies on g-C<sub>3</sub>N<sub>4</sub>: New Insight into Structure, Optical, and Vibrational Properties
Graphitic carbon nitride (g-C<sub>3</sub>N<sub>4</sub>) has emerged as one of the most promising solar-light-activated polymeric metal-free semiconductor photocatalysts due to its thermal physicochemical stability but also its characteristics of environmentally friendly and s...
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MDPI AG
2023-05-01
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| Online Access: | https://www.mdpi.com/1996-1944/16/10/3644 |
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| author | Paolo Negro Federico Cesano Silvia Casassa Domenica Scarano |
| author_facet | Paolo Negro Federico Cesano Silvia Casassa Domenica Scarano |
| author_sort | Paolo Negro |
| collection | DOAJ |
| description | Graphitic carbon nitride (g-C<sub>3</sub>N<sub>4</sub>) has emerged as one of the most promising solar-light-activated polymeric metal-free semiconductor photocatalysts due to its thermal physicochemical stability but also its characteristics of environmentally friendly and sustainable material. Despite the challenging properties of g-C<sub>3</sub>N<sub>4</sub>, its photocatalytic performance is still limited by the low surface area, together with the fast charge recombination phenomena. Hence, many efforts have been focused on overcoming these drawbacks by controlling and improving the synthesis methods. With regard to this, many structures including strands of linearly condensed melamine monomers, which are interconnected by hydrogen bonds, or highly condensed systems, have been proposed. Nevertheless, complete and consistent knowledge of the pristine material has not yet been achieved. Thus, to shed light on the nature of polymerised carbon nitride structures, which are obtained from the well-known direct heating of melamine under mild conditions, we combined the results obtained from XRD analysis, SEM and AFM microscopies, and UV-visible and FTIR spectroscopies with the data from the Density Functional Theory method (DFT). An indirect band gap and the vibrational peaks have been calculated without uncertainty, thus highlighting a mixture of highly condensed g-C<sub>3</sub>N<sub>4</sub> domains embedded in a less condensed “melon-like” framework. |
| first_indexed | 2024-03-11T03:32:35Z |
| format | Article |
| id | doaj.art-b6398fe009a14aa5a2ead10412fadda4 |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-11T03:32:35Z |
| publishDate | 2023-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Materials |
| spelling | doaj.art-b6398fe009a14aa5a2ead10412fadda42023-11-18T02:14:02ZengMDPI AGMaterials1996-19442023-05-011610364410.3390/ma16103644Combined DFT-D3 Computational and Experimental Studies on g-C<sub>3</sub>N<sub>4</sub>: New Insight into Structure, Optical, and Vibrational PropertiesPaolo Negro0Federico Cesano1Silvia Casassa2Domenica Scarano3Department of Chemistry and NIS (Nanostructured Interfaces and Surfaces) Interdepartmental Centre, University of Torino & INSTM-UdR Torino, Via P. Giuria 7, 10125 Torino, ItalyDepartment of Chemistry and NIS (Nanostructured Interfaces and Surfaces) Interdepartmental Centre, University of Torino & INSTM-UdR Torino, Via P. Giuria 7, 10125 Torino, ItalyDepartment of Chemistry and NIS (Nanostructured Interfaces and Surfaces) Interdepartmental Centre, University of Torino & INSTM-UdR Torino, Via P. Giuria 7, 10125 Torino, ItalyDepartment of Chemistry and NIS (Nanostructured Interfaces and Surfaces) Interdepartmental Centre, University of Torino & INSTM-UdR Torino, Via P. Giuria 7, 10125 Torino, ItalyGraphitic carbon nitride (g-C<sub>3</sub>N<sub>4</sub>) has emerged as one of the most promising solar-light-activated polymeric metal-free semiconductor photocatalysts due to its thermal physicochemical stability but also its characteristics of environmentally friendly and sustainable material. Despite the challenging properties of g-C<sub>3</sub>N<sub>4</sub>, its photocatalytic performance is still limited by the low surface area, together with the fast charge recombination phenomena. Hence, many efforts have been focused on overcoming these drawbacks by controlling and improving the synthesis methods. With regard to this, many structures including strands of linearly condensed melamine monomers, which are interconnected by hydrogen bonds, or highly condensed systems, have been proposed. Nevertheless, complete and consistent knowledge of the pristine material has not yet been achieved. Thus, to shed light on the nature of polymerised carbon nitride structures, which are obtained from the well-known direct heating of melamine under mild conditions, we combined the results obtained from XRD analysis, SEM and AFM microscopies, and UV-visible and FTIR spectroscopies with the data from the Density Functional Theory method (DFT). An indirect band gap and the vibrational peaks have been calculated without uncertainty, thus highlighting a mixture of highly condensed g-C<sub>3</sub>N<sub>4</sub> domains embedded in a less condensed “melon-like” framework.https://www.mdpi.com/1996-1944/16/10/3644graphitic carbon nitridesmelon polymorph structureDFT-D3 computationstructure and morphological propertiesoptical propertiesvibrational properties |
| spellingShingle | Paolo Negro Federico Cesano Silvia Casassa Domenica Scarano Combined DFT-D3 Computational and Experimental Studies on g-C<sub>3</sub>N<sub>4</sub>: New Insight into Structure, Optical, and Vibrational Properties Materials graphitic carbon nitrides melon polymorph structure DFT-D3 computation structure and morphological properties optical properties vibrational properties |
| title | Combined DFT-D3 Computational and Experimental Studies on g-C<sub>3</sub>N<sub>4</sub>: New Insight into Structure, Optical, and Vibrational Properties |
| title_full | Combined DFT-D3 Computational and Experimental Studies on g-C<sub>3</sub>N<sub>4</sub>: New Insight into Structure, Optical, and Vibrational Properties |
| title_fullStr | Combined DFT-D3 Computational and Experimental Studies on g-C<sub>3</sub>N<sub>4</sub>: New Insight into Structure, Optical, and Vibrational Properties |
| title_full_unstemmed | Combined DFT-D3 Computational and Experimental Studies on g-C<sub>3</sub>N<sub>4</sub>: New Insight into Structure, Optical, and Vibrational Properties |
| title_short | Combined DFT-D3 Computational and Experimental Studies on g-C<sub>3</sub>N<sub>4</sub>: New Insight into Structure, Optical, and Vibrational Properties |
| title_sort | combined dft d3 computational and experimental studies on g c sub 3 sub n sub 4 sub new insight into structure optical and vibrational properties |
| topic | graphitic carbon nitrides melon polymorph structure DFT-D3 computation structure and morphological properties optical properties vibrational properties |
| url | https://www.mdpi.com/1996-1944/16/10/3644 |
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