In situ preparation of g-C3N4/polyaniline hybrid composites with enhanced visible-light photocatalytic performance
Graphical abstract
Introduction
The environment pollution and energy shortage are considered as two of the major issues that threaten the survival of humans (Dong et al., 2017; Ren et al., 2019; Yu et al., 2018). In this context, photocatalysis as an effective and clean technology has been treated as the most promising strategy for healing environmental issues, such as purification of organic wastewater, inactivation of microorganism, hydrogen evolution and so on (Tang et al., 2019). In the past decades, many semiconductor such as metal-organic-frameworks (MOFs), TiO2, SnS2 and graphic carbon nitride (g-C3N4) have been reported as useful photocatalysts for both photocatalytic degradation organic pollutions and photocatalytic hydrogen production from water (He et al., 2018; Zhou et al., 2018).
Recently, g-C3N4 has attracted boosting attention because of its low cost, non-toxicity and good stability (Dong et al., 2018; Fan et al., 2017; Guo et al., 2018). Furthermore, it also exhibits the intrinsic features of the suitable band structure and the appropriate optical absorption (Jiang et al., 2016b; Kumar et al., 2017). As a consequence, g-C3N4 has been widely employed in photocatalytic applications for water splitting, environmental pollution purification and initiate carbon dioxide reduction reactions (Qin et al., 2019; Yang et al., 2016). Nevertheless, the high recombination rate of photo-generated charge and the lack of absorption visible light still retard the practical applications of g-C3N4 (Zhang et al., 2014a, 2014b). In this regard, key methods have been carried out to augment the photocatalytic efficiency of g-C3N4, such as doping, morphology tailoring, coupling with other semiconductors and so on (Duan et al., 2018; Luo et al., 2018). Especially, coupling with other semiconductors is considered as a promising solution to reduce the recombination rate of active species (Al Angari et al., 2018; Ćirić-Marjanović, 2013; He et al., 2018). Among various kinds of semiconductors tested so far, polyaniline (PANI) was brought to the forefront due to its low cost, excellent environmental stability and high conductivity. PANI is one of the best conductive polymers with a delocalized π-π conjugated structure, leading to the high absorption coefficient in the visible light and high charge separation efficiency (Li et al., 2016; Reddy et al., 2015; Tao et al., 2018; Zhao et al., 2018). For the past few years, PANI was used to modify some photocatalysts for constructing composites with advanced photocatalytic performances, like PANI@ZnO (Gilja et al., 2018; Zhu et al., 2018), PANI@MgIn2S4 (Xu et al., 2019), PANI@Ag3PO4 (Liu et al., 2017b) and PANI@SnS2 (Dionysiou et al., 2018; Zhang et al., 2017). It can be found that the significantly improvement of photocatalytic performance is attributed to the combination between PANI and other semiconductor photocatalyst, in which PANI can effectively restrain the recombination rate of photo-generated carriers and then promote the photocatalytic activity. Therefore, it is expected that the photocatalytic activity of the g-C3N4/PANI hybrid would be efficiently improved. Ge et al. (2012) found that the prepared g-C3N4/PANI photocatalysts could be effectively used for photocatalytic oxidation of Methylene Blue (MB) due to the synergistic effect between PANI and g-C3N4. Jiang et al. (2016a) fabricated PANI/g-C3N4 composite hydrogel via in situ polymerization for removing MB through adsorption and photocatalysis, which presented a new idea of the construction of three dimensional (3D) hierarchical photocatalysts. However, studies on the synthesis of g-C3N4/PANI catalysts with high photocatalytic activities toward synchronous antibiotic-containing wastewater removal and H2 evolution are rare.
Herein, we report an innovative g-C3N4/PANI photocatalysts with enhanced photocatalytic properties prepared by a facile in-situ polymerization process. The photocatalytic activity of the composites was evaluated by the degradation of antibiotic-containing wastewater under simulated-sunlight irradiation. The results show that the PANI loading greatly improved the photocatalytic activities of g-C3N4. In addition, the hydrogen production performance of g-C3N4/PANI is also explored in this study. Such a g-C3N4/PANI hybrid composites can be assumed to possess great potentials in practical wastewater treatment and photocatalytic hydrogen evolution.
Section snippets
1. Materials and methods
Details of this section can be found in Appendix A. Supplementary data. The g-C3N4/PANI hybrid with different weight ratios of PANI (3, 5, 7 and 10 wt.%) based on the total weight of g-C3N4 and aniline is denoted as X%PANI, and X stands for the content of polyaniline.
2. Results and discussion
The catalytic activities of the as-prepared catalysts were evaluated by degradation of oxytetracycline (OTC) under simulated-sunlight illumination (350 W Xenon lamp, Beijing China Education Au-light Co., Ltd, China) for 100 min. As shown in Fig. 1a, the photocatalytic efficiency of pure g-C3N4 and PANI are 16.7% and 14.3%, respectively. The photocatalytic performance is significantly enhanced by employing g-C3N4/PANI hybrid (3%PANI - 10%PANI), where almost 88.1% OTC could be photodegraded in
3. Conclusions
In this work, the g-C3N4/PANI was synthesized by a simple In-situ polymerization process. From these results, it was found that the degradation efficiency of OTC using 5%PANI is significantly higher than that of pure g-C3N4 under simulated-sunlight irradiation. The enhancement has been investigated in relation to the augmented visible light absorption and fast separation of photo-generated carriers, which is ultimately due to the forming of the heterojunction interface between g-C3N4 and PANI.
Acknowledgments
This work was supported by the NSFC (Nos. 21677047 and U1604137), the Innovation Scientists and Technicians Troop Construction Projects, the Research Start-up Foundation (No. 5101219170107), the Youth Science Foundation (No. 2015QK29) of Henan Normal University for the PhD, the Key Scientific and Technological Projects in Henan Province (No. 132102210129), research fund from Henan Normal University (Nos. 5101039170157 and 5101039170304) and Postdoctoral Science Foundation of Henan Province (No.
References (41)
Recent advances in polyaniline research: polymerization mechanisms, structural aspects, properties and applications
Synth. Met.
(2013)- et al.
Crystal structure and photocatalytic properties of perovskite MSn(OH)6 (M = Cu and Zn) composites with d10-d10 configuration
Appl. Surf. Sci.
(2019) - et al.
Self-assembled hollow sphere shaped Bi2WO6/RGO composites for efficient sunlight-driven photocatalytic degradation of organic pollutants
Chem. Eng. J.
(2017) - et al.
A simple fabrication for sulfur doped graphitic carbon nitride porous rods with excellent photocatalytic activity degrading RhB dye
Appl. Surf. Sci.
(2017) - et al.
Photocatalytic activity and photoelectric performance enhancement for ZnWO4 by fluorine substitution
J. Mol. Catal. A Chem.
(2011) - et al.
Enhancement of catalytic activity and oxidative ability for graphitic carbon nitride
J. Photoch. Photobio. C
(2016) - et al.
Microwave-assisted molten-salt rapid synthesis of isotype triazine-/heptazine based g-C3N4 heterojunctions with highly enhanced photocatalytic hydrogen evolution performance
Appl. Catal. B Environ.
(2017) - et al.
A stable Ag3PO4@PANI core@shell hybrid: enrichment photocatalytic degradation with π-π conjugation
Appl. Catal. B Environ.
(2017) - et al.
Rational and green synthesis of novel two-dimensional WS2/MoS2 heterojunction via direct exfoliation in ethanol-water targeting advanced visible-light-responsive photocatalytic performance
J. Colloid Interface Sci.
(2018) - et al.
In-situ oxidative polymerization of aniline on hydrothermally synthesized MoSe2 for enhanced photocatalytic degradation of organic dyes
J. Saudi Chem. Soc.
(2019)
Hybrid nanostructures based on titanium dioxide for enhanced photocatalysis
Appl. Catal. A Gen.
Synergistic effect of adsorption and photocatalysis of 3D g-C3N4-agar hybrid aerogels
Appl. Surf. Sci.
Noble metal-free ternary MoS2/Zn0.5Cd0.5S/g-C3N4 heterojunction composite for highly efficient photocatalytic H2 production
Mater. Res. Bull.
Facile fabrication of acidified g-C3N4/g-C3N4 hybrids with enhanced photocatalysis performance under visible light irradiation
Appl. Catal. B Environ.
Molecular engineering of polymeric carbon nitride for highly efficient photocatalytic oxytetracycline degradation and H2O2 production
Appl. Catal. B Environ.
Boron nitride quantum dots decorated ultrathin porous g-C3N4: intensified exciton dissociation and charge transfer for promoting visible-light-driven molecular oxygen activation
Appl. Catal. B Environ.
One-pot fabrication of beta-Bi2O3@Bi2S3 hierarchical hollow spheres with advanced sunlight photocatalytic RhB oxidation and Cr(VI) reduction activities
Appl. Surf. Sci.
Polyaniline modified SnS2 as a novel efficient visible-light-driven photocatalyst
Mater. Lett.
Design of a direct Z-scheme photocatalyst: preparation and characterization of Bi2O3/g-C3N4 with high visible light activity
J. Hazard. Mater.
In situ preparation of highly stable polyaniline/W18O49 hybrid nanocomposite as efficient visible light photocatalyst for aqueous Cr(VI) reduction
J. Hazard. Mater.
Cited by (41)
Highly efficient photocatalytic degradation of methyl orange dye under solar light using Polyaniline@Iron phosphate nanocomposite
2024, Materials Science and Engineering: BApplication of polyaniline-based photocatalyst in photocatalytic degradation of micropollutants in water: A review
2024, Journal of Water Process EngineeringConstruction of novel tandem reaction system coupling H<inf>2</inf>O<inf>2</inf> production with in situ bleaching over Au/TiO<inf>2</inf> photocatalyst with different metal-support interactions
2024, Process Safety and Environmental Protection