SBA-15 assisted preparation of mesoporous g-C3N4 for photocatalytic H2 production and Au3+ fluorescence sensing

• Published in: Applied surface science 2019-09, Vol.488, p.205-212
• Main Authors: Obregón, S., Vázquez, A., Ruíz-Gómez, M.A., Rodríguez-González, V.
• Format: Article
• Language: English
• Subjects: Fluorescence quenching; Hydrogen; Mpg-C3N4; SBA-15; Sensor
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2019.05.231

In the present work, we report the preparation of mesoporous graphitic-like carbon nitride (mpg-C3N4) using SBA-15 as hard template agent. The mpg-C3N4 exhibited a hypsochromic shift in the UV–vis absorption profile probably due to a lower degree of condensation of the tris-s-triazine units in its conjugate aromatic system. In addition, the mesoporous material demonstrated enhanced textural properties with a surface area estimated in 49.8 m2/g, which is one order of magnitude higher than the surface area of the bulk g-C3N4 sample. In this sense, the mpg-C3N4 shows a higher photocatalytic performance in the production of H2 through the water splitting process. Furthermore, the mpg-C3N4 was also used as fluorescent probe for the sensitive detection of Au3+ ions in aqueous solution. The fluorescence quenching was quantitatively analyzed by the Stern-Volmer equation using the evolution of the photoluminescence (PL) emission at 371 nm (λexc = 250 nm). The limit of detection (LOD) was estimated at 1.1 μM, which was lower than the estimated LOD using the bulk g-C3N4 sample (2.1 μM). To the best of our knowledge, this work reports for the first time the detection of Au3+ ions through fluorescence quenching using g-C3N4 samples with different textural properties. [Display omitted] •Mesoporous g-C3N4 was prepared using SBA-15 as hard template agent.•The mesoporous material showed a high photocatalytic hydrogen production.•Mpg-C3N4 was used as a fluorescent probe for the sensitive detection of Au3+ ions.•This work reports for the first time the detection of Au3+ ions using g-C3N4.