Jump to main content
Jump to site search

Issue 20, 2018
Previous Article Next Article

Three-dimensional bandgap-tuned Ag2S quantum dots/reduced graphene oxide composites with enhanced adsorption and photocatalysis under visible light

Author affiliations

Abstract

The pursuit of photodegrading environmental pollutants while efficiently utilizing solar energy remains a pivotal endeavor. Herein, Ag2S quantum dots (QDs)/reduced graphene oxide (rGO) composites with Ag2S QDs dispersed on porous stereoscopic rGO-based network were synthesized through a facile hydrothermal process without the addition of any other reducing agent or cross-linker. The as-obtained composites exhibited enhanced adsorption and photocatalysis performance under visible light because of the individual and synergistic effects. The hierarchically stereoscopic structure led to outstanding adsorption ability due to large specific surface area and spongy nature, which facilitated connection between the contaminants and the photocatalytic sites. The incorporation of rGO also suppressed the recombination of electron–hole pairs in the semiconductor and favored the separation from wastewater. Ag2S QDs, whose properties were influenced by quantum size effect, displayed a widened bandgap of 1.82 eV rather than initial 0.92 eV, attributing to stronger redox potential to degrade organic pollutants while efficiently absorbing the visible portion of solar light. With methyl orange as the model pollutant, the comprehensively optimized sample obtained at 150 °C exhibited adsorption capacity of 260 mg g−1 at 25 °C and photodegradation rate 7.8 times that of commercial TiO2 nanoparticles under visible light. Phenol was also analyzed to remove the influence of photosensitization of dyes. Our investigation gives a new insight into the design and fabrication of narrow band semiconductor/rGO composites with enhanced adsorption and photocatalysis.

Graphical abstract: Three-dimensional bandgap-tuned Ag2S quantum dots/reduced graphene oxide composites with enhanced adsorption and photocatalysis under visible light

Back to tab navigation

Supplementary files

Publication details

The article was received on 24 Jul 2018, accepted on 24 Aug 2018 and first published on 28 Aug 2018


Article type: Paper
DOI: 10.1039/C8CY01522H
Citation: Catal. Sci. Technol., 2018,8, 5225-5235
  •   Request permissions

    Three-dimensional bandgap-tuned Ag2S quantum dots/reduced graphene oxide composites with enhanced adsorption and photocatalysis under visible light

    Q. Wu, M. Zhou, Y. Gong, Q. Li, M. Yang, Q. Yang and Z. Zhang, Catal. Sci. Technol., 2018, 8, 5225
    DOI: 10.1039/C8CY01522H

Search articles by author

Spotlight

Advertisements