Enhancing Free Cyanide Photocatalytic Oxidation by rGO/TiO<sub>2</sub> P25 Composites
Graphene-TiO<sub>2</sub> composites have been investigated in various photocatalytic reactions showing successful synergy compared to pristine TiO<sub>2</sub>. In the present work, graphene oxide (GO) was synthesized by the Hummers method and then reduced graphene oxide-TiO&l...
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MDPI AG
2022-07-01
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| Online Access: | https://www.mdpi.com/1996-1944/15/15/5284 |
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| author | Elim Albiter Jose M. Barrera-Andrade Lina A. Calzada Jesús García-Valdés Miguel A. Valenzuela Elizabeth Rojas-García |
| author_facet | Elim Albiter Jose M. Barrera-Andrade Lina A. Calzada Jesús García-Valdés Miguel A. Valenzuela Elizabeth Rojas-García |
| author_sort | Elim Albiter |
| collection | DOAJ |
| description | Graphene-TiO<sub>2</sub> composites have been investigated in various photocatalytic reactions showing successful synergy compared to pristine TiO<sub>2</sub>. In the present work, graphene oxide (GO) was synthesized by the Hummers method and then reduced graphene oxide-TiO<sub>2</sub> composites (rGO/TiO<sub>2</sub>) were obtained by an in situ GO photoreduction route. X-ray diffraction, FTIR, Raman, UV–vis DRS, and photoluminescence were the main characterization techniques. The obtained composites containing 1 and 3 wt.% rGO were evaluated in the cyanide (50 mg/L) oxidation and Au-cyanide complex (300 mg/L) degradation under UV-A light. The composites showed higher photocatalytic activity than TiO<sub>2</sub>, mainly with the 1% rGO content. Cyanate and gold nanoparticles, deposited on the photocatalyst’s surface, were the main byproducts during the photocatalyst assessment. The improved photocatalytic activity of the composites was attributed to a higher rate of electron transfer and a lower rate of charge recombination due to the chemical interaction of rGO with TiO<sub>2</sub>. |
| first_indexed | 2024-03-09T05:16:02Z |
| format | Article |
| id | doaj.art-79e145e0386146cb80c424574de0ae79 |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-09T05:16:02Z |
| publishDate | 2022-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Materials |
| spelling | doaj.art-79e145e0386146cb80c424574de0ae792023-12-03T12:45:46ZengMDPI AGMaterials1996-19442022-07-011515528410.3390/ma15155284Enhancing Free Cyanide Photocatalytic Oxidation by rGO/TiO<sub>2</sub> P25 CompositesElim Albiter0Jose M. Barrera-Andrade1Lina A. Calzada2Jesús García-Valdés3Miguel A. Valenzuela4Elizabeth Rojas-García5Laboratorio de Catálisis y Materiales, ESIQIE-Instituto Politécnico Nacional, Zacatenco, Ciudad de México 07738, MexicoLaboratorio de Catálisis y Materiales, ESIQIE-Instituto Politécnico Nacional, Zacatenco, Ciudad de México 07738, MexicoLaboratorio de Catálisis y Materiales, ESIQIE-Instituto Politécnico Nacional, Zacatenco, Ciudad de México 07738, MexicoDepartamento de Química Analítica, Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, Ciudad de México 04510, MexicoLaboratorio de Catálisis y Materiales, ESIQIE-Instituto Politécnico Nacional, Zacatenco, Ciudad de México 07738, MexicoÁrea de Ingeniería Química, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, Iztapalapa, Ciudad de México 09340, MexicoGraphene-TiO<sub>2</sub> composites have been investigated in various photocatalytic reactions showing successful synergy compared to pristine TiO<sub>2</sub>. In the present work, graphene oxide (GO) was synthesized by the Hummers method and then reduced graphene oxide-TiO<sub>2</sub> composites (rGO/TiO<sub>2</sub>) were obtained by an in situ GO photoreduction route. X-ray diffraction, FTIR, Raman, UV–vis DRS, and photoluminescence were the main characterization techniques. The obtained composites containing 1 and 3 wt.% rGO were evaluated in the cyanide (50 mg/L) oxidation and Au-cyanide complex (300 mg/L) degradation under UV-A light. The composites showed higher photocatalytic activity than TiO<sub>2</sub>, mainly with the 1% rGO content. Cyanate and gold nanoparticles, deposited on the photocatalyst’s surface, were the main byproducts during the photocatalyst assessment. The improved photocatalytic activity of the composites was attributed to a higher rate of electron transfer and a lower rate of charge recombination due to the chemical interaction of rGO with TiO<sub>2</sub>.https://www.mdpi.com/1996-1944/15/15/5284free cyanidephotocatalytic oxidationAu–cyanide complexgraphene-TiO<sub>2</sub> compositesRamanFTIR |
| spellingShingle | Elim Albiter Jose M. Barrera-Andrade Lina A. Calzada Jesús García-Valdés Miguel A. Valenzuela Elizabeth Rojas-García Enhancing Free Cyanide Photocatalytic Oxidation by rGO/TiO<sub>2</sub> P25 Composites Materials free cyanide photocatalytic oxidation Au–cyanide complex graphene-TiO<sub>2</sub> composites Raman FTIR |
| title | Enhancing Free Cyanide Photocatalytic Oxidation by rGO/TiO<sub>2</sub> P25 Composites |
| title_full | Enhancing Free Cyanide Photocatalytic Oxidation by rGO/TiO<sub>2</sub> P25 Composites |
| title_fullStr | Enhancing Free Cyanide Photocatalytic Oxidation by rGO/TiO<sub>2</sub> P25 Composites |
| title_full_unstemmed | Enhancing Free Cyanide Photocatalytic Oxidation by rGO/TiO<sub>2</sub> P25 Composites |
| title_short | Enhancing Free Cyanide Photocatalytic Oxidation by rGO/TiO<sub>2</sub> P25 Composites |
| title_sort | enhancing free cyanide photocatalytic oxidation by rgo tio sub 2 sub p25 composites |
| topic | free cyanide photocatalytic oxidation Au–cyanide complex graphene-TiO<sub>2</sub> composites Raman FTIR |
| url | https://www.mdpi.com/1996-1944/15/15/5284 |
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