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[Display omitted] • A novel hierarchical UN/CDS/CAS hybrid material is prepared by a low temperature reflux route. • The heterostructure exhibited sulfur vacancy and strong interfacial contact. • Photo-electrochemical analysis confirmed fast channelization of photo-excited charge carriers. • The hybrid material displayed superior ASM degradation (0.02 min−1) and H 2 evolution (493-1 µmol g-1h−1) activity. • A dual S-scheme charge migration mechanism accounted for the improved activity. The in-situ fabrication of dual S-scheme ternary heterostructure is a promising approach to isolate photo-induced electron-hole and boost the efficiency of a semiconductor photocatalyst. However, the dual S-scheme heterostructure based on MOFs are rarely narrated. Herein, a S-vacancy rich hierarchical UiO-66(–NH 2)/CdIn 2 S 4 /CaIn 2 S 4 ternary hybrid material is successfully fabricated by in-situ preferential growth of ultrathin CaIn 2 S 4 nanosheets and CdIn 2 S 4 nanorods in presence of UiO-66(–NH 2) (UN) spherical nanoparticles by using a simple reflux route. The physiochemical characteristics and optoelectronic features of the developed materials are illustrated in detail. The efficacy of UiO-66(–NH 2)/CdIn 2 S 4 /CaIn 2 S 4 ternary hybrid material is explored for photocatalytic H 2 evolution reaction and decontamination of asulam (ASM) herbicide. The development of S-vacancy facilitates interfacial charge carrier migration and reduces the recombination rate. The enhanced photocatalytic H 2 production and ASM degradation could be ascribed to staggered band alignment between UiO-66(–NH 2) (UN), CdIn 2 S 4 (CDS) and CaIn 2 S 4 (CAS), which support S-scheme charge channelization in the heterojunction. Due to its physio-chemical advantages, the optimal 15UN/CDS/CAS30 hybrid photocatalyst exhibits highest photocatalytic H 2 evolution rate of 4931 μmol g−1h−1 with apparent conversion efficiency of 31.5% and ASM degradation > 93% (k = 0.02 min−1) under irradiation of visible light. This work furnishes a new perceptive into the in-situ construction of dual S-scheme photocatalytic systems for renewable energy production and decontamination of organic pollutants. In addition, this study for the first time illustrates mineralization of Asulam using a heterogeneous photocatalytic route. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bi- self doped Bi 2 MoO 6 with nanoplate morphology prepared by reflux route. • Bi self-doping induces part reduction of Mo6+ to Mo5+ and creation of Mo vacancy. • CaFe 2 O 4 /Bi 2 MoO 6 0D-2D p-n heterojunction fabricated by integrating CaFe 2 O 4 QDs. • Improved activity for bisphenol A (k app = 0.0132 min−1) degradation and Cr(VI) (k app = 0.15 min−1) reduction. • Reaction rates for p-n heterojunction 5–9 times higher than pure semiconductors. In this study, a mild reflux route was developed for facile synthesis of Bi-self doped Bi 2 MoO 6 (BMOR) with nanoplate morphology. Microstructural study revealed substitution of Bi5+ ions in the molybdate layer which resulted in partial reduction of Mo6+ to Mo5+ ions and creation of Mo vacancy. The defect engineered BMOR material exhibited improved optical and photoelectrochemical properties compared to its undoped analogue. The BMOR material was subsequently employed as host lattice for construction of CaFe 2 O 4 /Bi 2 MoO 6 0D-2D p-n heterojunctions by using an in situ preparative strategy. Well dispersed CaFe 2 O 4 quantum dots over BMOR nanoplates provide a strong interfacial contact conducive for fast charge mobilization. Comprehensive characterization of the composites revealed extended UV–vis response, improved charge carrier separation, prolonged excited state life time and robust radical generation efficiency compared to pure components. The CaFe 2 O 4 /Bi 2 MoO 6 composites displayed improved photocatalytic performance for bisphenol A (BPA) degradation (k app = 0.0132 min−1) and Cr(VI) reduction (k app = 0.15 min−1) with reaction rates 5–9 times higher than pure components. The involvement of •OH and •O 2 − radicals in the photodegradation of BPA was confirmed from radical trapping study. The formation of an interfacial p-n heterojunction and a double charge migration mechanism accounted for the improved photocatalytic efficacy of the composite. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bi 2 O 3 /CuBi 2 O 4 and CuO/CuBi 2 O 4 materials synthesized by one step combustion method. • Plasmonic Ag nanoparticles photo-deposited over binary Bi 2 O 3 /CuBi 2 O 4 material. • Enhanced photocatalytic activity observed for 17α-ethynylestradiol degradation and Cr(VI) reduction. • Significant increase in photoelectrochemical and charge carrier separation property. • Improved activity is due to step scheme junction and surface Plasmon Ag cocatalyst. In this study, we have developed a facile and less time consuming one pot solution combustion method to prepare Bi 2 O 3 /CuBi 2 O 4 (BO/CBO) and CuO/CuBi 2 O 4 (CO/CBO) heterojunction materials by optimizing the Cu/Bi/urea molar ratio. The as prepared optimal Bi 2 O 3 /CuBi 2 O 4 binary material was further modified by plasmonic Ag nanoparticles to construct Bi 2 O 3 /CuBi 2 O 4 /Ag (BO/CBO/Ag) ternary composite material. Comprehensive characterization of the ternary composite using a variety of techniques confirmed fast electron channelization, improved charge carrier separation and prolonged life time of the excited state. The ternary composite exhibited excellent photocatalytic activity for 17-α Ethinylestradiol (EE2) degradation (94.6%) and Cr(VI) reduction (96.9%) under visible light irradiation with an apparent rate constant value of 0.0185 min−1 and 0.1147 min−1 , respectively. The hydroxyl (•OH) and superoxide (•O 2 −) radicals were identified as the major active species responsible for photocatalytic action. The electron transfer mechanism in BO/CBO/Ag material is probed using photoelectrochemical characterization and spectroscopic method (PL, UV–Vis and ESR) employing different molecular probes. The substantially staggered band alignment between the BO and CBO semiconductors and formation of an internal electric field at the interfacial region ensures smooth passage of electron from the CB of BO to the VB of CBO forming a step (S) scheme heterojunction. The Ag metal acts as an electron reservoir as well as surface Plasmon which help in achieving higher charge carrier separation and improved photocatalytic activity. [ABSTRACT FROM AUTHOR]

• A novel UiO-66/CdIn 2 S 4 heterostructure material is devised by integrating CdIn 2 S 4 nanosheets with UiO-66 nanoparticles. • Hierarchical 3D- microflower structure with high surface area, large interfacial contact and improved optical absorption. • A constructive band alignment facilitates easy migration of electrons from CB of CIS to UiO-66. • Photoelectrochemical study confirms better channelization of charge carriers and high resistance to recombination. • UiO-66/CIS nanocomposites exhibit efficient TCS degradation (0.0094 min−1) and H 2 production (2950 μmol g-1 h-1) activity. Construction of porous heterostructure photocatalyst material with improved surface and optoelectrical properties is a practical and effective strategy for mineralization of toxic organic pollutants and water splitting reaction under visible light irradiation. Herein, we have developed a facile hydrothermal route to prepare a series of novel UiO-66/CdIn 2 S 4 heterojunction nanocomposite materials containing finely dispersed UiO-66 spherical nanoparticles (20−40 nm) anchored over high aspect ratio CdIn 2 S 4 nanosheets. Comprehensive characterization of the UiO-66/CdIn 2 S 4 nanocomposites revealed a hierarchical 3D microflower structure with enhanced surface reactive sites, better channelization of charge carriers, high resistance to charge recombination and a favorable band alignment between the two semiconductor components. The optimal photocatalyst (30UiO-66/CdIn 2 S 4) showed improved photocatalytic efficiency towards triclosan degradation with rate constant (0.0094 min−1) twelve times higher than the pure CdIn 2 S 4 (0.0007 min−1). The 30UiO-66/CdIn 2 S 4 photocatalyst also exhibited higher H 2 evolution rate (2.95 mmolg−1 h−1) with apparent conversion efficiency of 20.8 %. [ABSTRACT FROM AUTHOR]

• A simple one pot hydrothermal method is designed for synthesis of CdS/BiOBr/Bi 2 O 2 CO 3 heterostructure photocatalyst. • A double z-scheme electron transfer process leads to enhanced separation and migration of charge carriers. • Improved optical and photoelectrochemical properties and prolonged life time due to high interfacial contact. • The ternary heterostructre show excellent photocatalytic activity for mineralization of atrazine herbicide. • MTT assay study confirms the non-cytotoxic nature of the treated aqueous solution of atrazine. In this study, a simple one-step hydrothermal method was developed for morphology controlled synthesis of CdS/BiOBr/Bi 2 O 2 CO 3 ternary heterostructure materials. The ternary system contained well dispersed CdS nanoparticles (50–80 nm) anchored over ultrathin BiOBr and Bi 2 O 2 CO 3 nanoplates with high interfacial contact. A significant enhancement in visible light absorption, prolonged life time decay and improved charge carrier separation and migration property accounted for the excellent photocatalytic activity towards atrazine herbicide degradation (>95% in 30 min). A double Z-scheme electron transfer mechanism was proposed to explain the dramatic increase in photocatalytic activity which was deduced from photoelectrochemical measurements, scavenger and radical (OH and O 2 ‾) trapping experiments. MTT assay study revealed that the photo-catalytically treated atrazine solution showed significant reduction in cytotoxicity. This study provides an effective strategy for facile synthesis of bismuth based ternary heterostructures with potential applications in the field of environmental remediation. [ABSTRACT FROM AUTHOR]