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Promoting the separation of photogenerated electron–hole pairs and enhancing the charge carrier transfer are critical in photocatalysis. In our work, a ball-flower-like NiS/Zn3In2S6/g-C3N4 photocatalyst fabricated by a hydrothermal method exhibited superior performance for photocatalytic water splitting. The optimized 2.0% NiS/Zn3In2S6/g-C3N4 rivaled noble metal based Pt/g-C3N4 and showed an apparent quantum efficiency (AQE) of 24.3% at 420 nm, with a H2 yield of 4.135 mmol g−1 h−1, which was 30.4 and 9.51 times that of pure g-C3N4 and binary Zn3In2S6/g-C3N4 composites, respectively. The experimental and characterization results suggested that the heterojunction formed between Zn3In2S6/g-C3N4 and the decorating NiS co-catalyst cooperatively suppressed the electron–hole recombination and facilitated the charge carrier transfer, thus resulting in significant improvement of the H2 evolution performance. Moreover, the increased specific surface area and the enhanced visible-light absorption also contributed to superior water splitting performance. The prepared ternary catalytic system with the heterojunction and non-noble metal co-catalyst has great potential as an alternative to noble metals for achieving cost-efficient water splitting systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • NH 2 -UiO-66/CdIn 2 S 4 composite exhibited superior CO 2 photoreduction activity. • NH 2 -UiO-66/CdIn 2 S 4 could achieve the rapid separation of photoexcited e−/h+ pairs. • High CO 2 molecules adsorption activity of NH 2 -UiO-66/CdIn 2 S 4 composite. Solar-driven carbon dioxide (CO 2) photoreduction has been considered as an environmentally friendly and promising strategy to utilize solar energy and mitigate the impact of greenhouse effect. Designing novel cost-effective photocatalytic system with high CO 2 molecules adsorption activity is an efficient avenue to enhance CO 2 photoreduction performance. Herein, a series of NH 2 -UiO-66/CdIn 2 S 4 (NU66/CIS) photocatalysts with different NU66 contents were constructed via facile in-situ hydrothermal route and displayed graceful morphology. According to a series of characterization results, porous octahedron NU66 were deeply anchored on flowerlike 3D-microspheres CIS, and a part of the small-sized CIS were evenly dispersed on the surface of NU66. Without any sacrificial agent, the optimized 8% NU66/CIS heterojunctions still exhibited the satisfactory photocatalytic efficiency for CO 2 conversion, whose CO and CH 4 yields reached up to 11.24 μ mol g−1 h−1 and 2.92 μ mol g−1 h−1, respectively, which were 2.87 and 3.31 folds higher than that of pristine CIS. The remarkably boosted activity of NU66/CIS was originated from the high specific surface area and the formation of heterostructure between the well-dispersed NU66 and CIS, which could promote the electron transfer during CO 2 photocatalytic reduction. [ABSTRACT FROM AUTHOR]

Facilitating the separation of photoexcited electron-hole pairs and enhancing the migration of photogenerated carriers are essential in photocatalytic reaction. CoS/g-C 3 N 4 /NiS ternary photocatalyst was prepared by hydrothermal and physical stirring methods. The optimized ternary composite achieved a hydrogen yield of 1.93 mmol g−1 h−1, 12.8 times that of bare g-C 3 N 4 , with an AQE of 16.4% at 420 nm. The enhanced photocatalytic activity of CoS/g-C 3 N 4 /NiS was mainly ascribed to the synergistic interaction between the Z-scheme heterojunction constructed by CoS and g-C 3 N 4 and the NiS co-catalyst featuring a large amount of hydrogen precipitation sites, which realized the efficient separation and migration of photogenerated carriers. In addition, the CoS/g-C 3 N 4 /NiS heterojunction-co-catalyst system exhibited excellent photocatalytic stability and recyclability. • CoS/g-C 3 N 4 /NiS ternary photocatalyst was prepared by hydrothermal and physical stirring methods. • A large amount of hydrogen precipitation sites are available on CoS/g-C 3 N 4 /NiS ternary photocatalyst. • The Z-scheme heterojunction combined with the co-catalyst promoted the separation and migration of photogenerated carriers. [ABSTRACT FROM AUTHOR]

• Novel flower spherical-like Bi-Bi 7 O 9 I 3 /Ag-AgI S-scheme heterojunction was synthesized. • Dual plasmons (Bi, Ag) enhance the visible light absorption and photothermal effect. • The synergistic role of S-scheme heterojunction, SPR effect and photothermal effect contributed to the excellent phenol photodegradation and removal activity. • Theoretical calculation expressed Fermi energy levels and work function. The flower spherical-like S-scheme Bi 7 O 9 I 3 /AgI heterostructure was successfully fabricated through hydrothermal as well as calcination reduction method. The Ag and Bi nanoparticles generated during calcination reduction process are tightly fixed on surface of Bi 7 O 9 I 3 and AgI, severally, which was distinctly beneficial to the charge transfer. On account of the enhanced light absorption and surface plasma resonance of Ag and Bi, Bi-Bi 7 O 9 I 3 /Ag-AgI possessed conspicuous photothermal effect. The results show that Bi-Bi 7 O 9 I 3 /Ag-AgI possessesed the optimal photodegradation efficiency and TOC removal rate of phenol, which are 100% and 95.38% within 80 min and 120 min. The light-induced carriers could be efficaciously separated by establishing an S-scheme photocatalytic system. A possible photocatalytic degradation mechanism of the as-constructed samples was investigated by free radical capture experiment as well as EPR technique. In addition, the photocatalyst exhibited the high stability. This work will supply a new perspective with the synthesis of novel S-scheme heterostructure. [ABSTRACT FROM AUTHOR]

The development of photocatalytic technology can not only reduce CO 2 emissions, but also realize the effective utilization of solar energy, thus alleviating the global energy crisis. In this work, BiOIO 3 /g-C 3 N 4 Z-scheme heterojunction modified by Ti 3 C 2 nanosheets was designed and fabricated through hydrothermal method and electrostatic self-assembly strategy. The g-C 3 N 4 /BiOIO 3 /Ti 3 C 2 (4 wt%) photocatalytic system exhibited the optimal photocatalytic efficiency, reaching 5.88 and 1.55 μ mol/g/h for CO and CH 4 , respectively, and the CO production rate was 6.6 folds as high as that of bare g-C 3 N 4. Various characterization techniques were utilized to research the physicochemical properties of as-prepared photocatalysts. Z-scheme heterojunction formed between g-C 3 N 4 and BiOIO 3 and the decorating of 2D Ti 3 C 2 co-catalyst were responsible for the boosted photocatalytic behavior. Z-scheme heterojunction could prevent the recombination of charge carriers, the co-catalyst Ti 3 C 2 acted as electron sink could achieve quick shift of photo-induced electrons and supply numerous active sites for photocatalytic reaction. [Display omitted] [ABSTRACT FROM AUTHOR]

S-scheme heterostructure can facilitate the separation of carriers while maintain outstanding redox capacity. A series of ternary Bi 7 O 9 I 3 /g-C 3 N 4 /Bi 3 O 4 Cl photocatalytic system was triumphantly synthesized via oil bath method in this work and used in photocatalytic degradation of phenol. The optimal TOC removal rate reached up to 93.57% under illumination for 160 min, which was slightly lower than phenol photodegradation (about 100%, 100 min). Correspondingly, the apparent rate constants for the decay of phenol are determined to be 0.0211 min−1. The experiment of free radical capture indicated that ·OH and ·O 2 − were the major oxidizing substances to degrade phenol. The products of phenol photodegradation were identified by high performance liquid chromatography (HPLC) and a possible degradation pathway was proposed. The characterization analysis and density functional theory (DFT) calculations demonstrated that dual S-scheme charge migration was generated at the interface of Bi 7 O 9 I 3 , g-C 3 N 4 and Bi 3 O 4 Cl, contributing to an efficient separation of light-excited carriers. In the field of environmental remediation, the discovery of this work could open up promising vistas for designing bismuth-based ternary heterostructures with application potentiality. [Display omitted] • Flower spherical-like Bi 7 O 9 I 3 /g-C 3 N 4 /Bi 3 O 4 Cl was synthesized by oil bath method. • Bi 7 O 9 I 3 /g-C 3 N 4 /Bi 3 O 4 Cl heterojunction with enhanced phenol degradation activity. • ·OH and ·O 2 − were the major oxidizing substances to degrade phenol. • Bi 7 O 9 I 3 /g-C 3 N 4 /Bi 3 O 4 Cl composite followed dual S-scheme heterojunction photocatalytic mechanism. • Dual S-scheme Bi 7 O 9 I 3 /g-C 3 N 4 /Bi 3 O 4 Cl heterojunction contribute to an efficient separation of light-excited carriers. [ABSTRACT FROM AUTHOR]