1
|
Pérez-Torres A, Hernández-Barreto DF, Bernal V, Giraldo L, Moreno-Piraján JC, da Silva EA, Alves MDCM, Morais J, Hernandez Y, Cortés MT, Macías MA. Sulfur-Doped g-C 3N 4 Heterojunctions for Efficient Visible Light Degradation of Methylene Blue. ACS Omega 2023; 8:47821-47834. [PMID: 38144128 PMCID: PMC10734029 DOI: 10.1021/acsomega.3c06320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 10/25/2023] [Accepted: 11/20/2023] [Indexed: 12/26/2023]
Abstract
The discharge of synthetic dyes from different industrial sources has become a global issue of concern. Enormous amounts are released into wastewater each year, causing concerns due to the high toxic consequences. Photocatalytic semiconductors appear as a green and sustainable form of remediation. Among them, graphitic carbon nitride (g-C3N4) has been widely studied due to its low cost and ease of fabrication. In this work, the synthesis, characterization, and photocatalytic study over methylene blue of undoped, B/S-doped, and exfoliated heterojunctions of g-C3N4 are presented. The evaluation of the photocatalytic performance showed that exfoliated undoped/S-doped heterojunctions with 25, 50, and 75 mass % of S-doped (g-C3N4) present enhanced activity with an apparent reaction rate constant (kapp) of 1.92 × 10-2 min-1 for the 75% sample. These results are supported by photoluminescence (PL) experiments showing that this heterojunction presents the less probable electron-hole recombination. UV-vis diffuse reflectance and valence band-X-ray photoelectron spectroscopy (VB-XPS) allowed the calculation of the band-gap and the valence band positions, suggesting a band structure diagram describing a type I heterojunction. The photocatalytic activities calculated demonstrate that this property is related to the surface area and porosity of the samples, the semiconductor nature of the g-C3N4 structure, and, in this case, the heterojunction that modifies the band structure. These results are of great importance considering that scarce reports are found concerning exfoliated B/S-doped heterojunctions.
Collapse
Affiliation(s)
- Andrés
F. Pérez-Torres
- Crystallography
and Chemistry of Materials, CrisQuimMat, Department of Chemistry, Universidad de los Andes, Bogotá D.C. 111711, Colombia
| | - Diego F. Hernández-Barreto
- Facultad
de Ciencias, Departamento de Química, Grupo de Investigación
en Sólidos Porosos y Calorimetría, Universidad de los Andes, Bogotá
D.C. 111711, Colombia
| | - Valentina Bernal
- Facultad
de Ciencias, Departamento de Química, Grupo de Investigación
en Sólidos Porosos y Calorimetría, Universidad de los Andes, Bogotá
D.C. 111711, Colombia
| | - Liliana Giraldo
- Facultad
de Ciencias, Departamento de Química, Grupo de Calorimetría, Universidad Nacional de Colombia, Sede Bogotá 01, Bogotá D.C. 111321, Colombia
| | - Juan Carlos Moreno-Piraján
- Facultad
de Ciencias, Departamento de Química, Grupo de Investigación
en Sólidos Porosos y Calorimetría, Universidad de los Andes, Bogotá
D.C. 111711, Colombia
| | - Edjan Alves da Silva
- Electron
Spectroscopy Lab (LEe-), Instituto de Física, Universidade Federal do Rio Grande do Sul (UFRGS), Avenida Bento Gonçalves, 9500, 91501-970 Porto Alegre, RS, Brazil
| | - Maria do Carmo Martins Alves
- Instituto
de Química, Universidade Federal
do Rio Grande do Sul (UFRGS), Avenida Bento Gonçalves, 9500, 91501-970 Porto Alegre, RS, Brazil
| | - Jonder Morais
- Electron
Spectroscopy Lab (LEe-), Instituto de Física, Universidade Federal do Rio Grande do Sul (UFRGS), Avenida Bento Gonçalves, 9500, 91501-970 Porto Alegre, RS, Brazil
| | - Yenny Hernandez
- Department
of Physics, Universidad de los Andes, Bogotá D.C. 111711, Colombia
| | - María T. Cortés
- Departamento
de Química, Universidad de los Andes, Bogotá D.C. 111711, Colombia
| | - Mario A. Macías
- Crystallography
and Chemistry of Materials, CrisQuimMat, Department of Chemistry, Universidad de los Andes, Bogotá D.C. 111711, Colombia
| |
Collapse
|