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Novel Z-scheme rGO/Bi 12 O 15 Cl 6 /InVO 4 ternary heterojunction photocatalyst was successfully prepared using reduced graphene oxide (rGO) as the electronic medium. The optimum sample 0.3% rGO/Bi 12 O 15 Cl 6 /InVO 4 can degrade 99.1% Rhodamine B (RhB) and 77.48% tetracycline (TC) in 75 min, and can inactivate Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) within 30 min under the LED light. The crystal structure, morphology, composition, specific surface area, photoelectric chemical properties, and photodegradation properties were studied. Compared with binary Bi 12 O 15 Cl 6 /InVO 4 and single photocatalyst, rGO/Bi 12 O 15 Cl 6 /InVO 4 ternary heterojunction photocatalyst presented the best degradation and antibacterial performance, which is mainly due to the introduction of rGO, which can enhance the absorption of photons, and the separation and migration efficiency of photoexcited carriers. The capture experiment of active substances showed that both h+ and •O 2 − were the main active substances in the photocatalytic process. The probable photocatalytic degradation pathway of TC was proposed by mass spectrometry (MS) determination of the intermediate. The experimental results show that Z-scheme rGO/Bi 12 O 15 Cl 6 /InVO 4 is a promising photocatalyst. [ABSTRACT FROM AUTHOR]

A novel S-scheme photocatalyst InVO 4 /Bi 5 O 7 I with a compact heterojunction structure was prepared by hydrothermal combined calcination method, which exhibited excellent photocatalytic performance at low dose and low energy consumption. The antimicrobial and degradation properties of the photocatalysts were evaluated by inactivating E. coli and S. aureus and degrading pollutants (TC and BPA) under LED light irradiation. The best sample was able to completely inactivate E. coli and S. aureus in 30 min, and the degradation rate of TC reached 76.0% in 60 min and that of BPA reached 93.0% in 90 min, and the active species produced in this process were e−, h+, O 2 − and OH. The synergistic effect of S-scheme heterojunction makes it possess excellent photocatalytic activity. [Display omitted] The low efficiency of charge carrier separation is a major limitation hindering the application of photocatalytic technology. Constructing S-scheme heterojunction photocatalysts not only effectively promotes the separation of charge carriers, but also maximizes the oxidative and reductive capabilities of the two monomers. In this study S-scheme heterogeneous InVO 4 /Bi 5 O 7 I photocatalyst was synthesized by hydrothermal method combined with calcination. The optimal sample 20 % InVO 4 /Bi 5 O 7 I can completely deactivate Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) in 30 min, remove 20 mg/L TC 76.0 % in 60 min and 20 mg/L BPA 93.0 % in 90 min. Intermediate products of TC and BPA degradation were detected using LC-MS, and possible degradation pathways were proposed. The photocurrent and electrochemical impedance spectroscopy (EIS) tests confirm that InVO 4 /Bi 5 O 7 I exhibits excellent photocurrent intensity and photocarrier migration ability, which are crucial reasons for the enhancement of the photocatalytic performance of the InVO 4 /Bi 5 O 7 I composite. Capture experiments indicate that OH, O 2 −, h+ and e−are reactive species. EPR further confirms the generation of OH and O 2 −. Combined with Kelvin probe force microscopy (KPFM) and band structure analysis, it is proposed that InVO 4 /Bi 5 O 7 I has an S-scheme charge transfer mechanism. [ABSTRACT FROM AUTHOR]

An efficient In3+ doped Bi 4 O 5 I 2 /In 2 O 3 photocatalyst was synthesized by simple solvothermal and calcination routes. Rhodamine B (RhB), tetracycline (TC) and Escherichia coli (E. coli) were evaluated as model pollutants for the photocatalytic measurement. Under LED light, the optimum sample BIN-2 can kill E. coli in 30 min, 78% of tetracycline (TC) in 75 min, and degrade 100% of RhB in 75 min. The trapping test proved that the superoxide anion radicals (•O 2 -) and holes (h+) played an important role in the photocatalytic process. The intermediates were revealed by mass spectrometry analysis (MS), and the proposed pathway of TC degradation was given. By trapping experiment and related characterizations, a tight Z-scheme was produced, in which In3+ doped Bi 4 O 5 I 2 /In 2 O 3 hybrid structure is realized with a more negative conduction band and a more positive valence band, facilitating the production of active substances and photocatalytic redox reaction. The enhanced photocatalytic activities could be attributed to the well visible light absorption, tight hybrid interface, and efficient separation of photo-generated charges. • A novel In3+ doped Bi 4 O 5 I 2 /In 2 O 3 photocatalyst was prepared. • In3+ doped Bi 4 O 5 I 2 /In 2 O 3 can effectively remove RhB, E. coli , and TC in LED light. • h+and •O 2 - played an important role in the degradation of photocatalytic process. • Tight heterojunction formed between In3+-doped Bi 4 O 5 I 2 porous nanosheets and In 2 O 3 nanoflowers. • A Z-scheme route promoted the separation and transition of charges. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C 3 N 4) is a promising photocatalyst for photocatalytic field, but how to construct an efficient g-C 3 N 4 nanosheet-based heterostructure is still a challenge by one-step method. In this study, we prepared WO 3-x /2D g-C 3 N 4 heterostructure by one-step calcination approach, which simultaneously produced g-C 3 N 4 nanosheet, heterostructure and oxygen vacancy. The photoactivity of WO 3-x /2D g-C 3 N 4 heterostructure was tested by removing Rhodamine B (RhB), tetracycline (TC) and S. aureus under LED light illumination. The enhanced photoactivity is attributed to the promoted transfer of charge carriers, the broadened light absorption and the increased surface area of composite, which arose from heterostructure, oxygen vacancy and g-C 3 N 4 nanosheet, respectively. This study offers insights into one-step preparation for new photocatalysts in environmental field. • WO 3-x /2D g-C 3 N 4 heterostructure was prepared by one-step calcination. • WO 3-x /2D g-C 3 N 4 can remove RhB, TC and S. aureus under a LED light. • Oxygen vacancy, 2D g-C 3 N 4 and heterostructure are beneficial for the photoactivity. • Oxygen vacancy assisted Z-scheme mechanism was presented. [ABSTRACT FROM AUTHOR]

Photocatalysis has been intensively used for wastewater remediation, but suffers from unsatisfactory efficiency for treating complex wastewater system, which includes antibiotic, organic dye and bacteria. Herein, we prepared novel SnO2−x/g-C3N4 photocatalysts and introduced oxygen vacancy by partial oxidation of Sn2+ under solvothermal condition. The oxygen vacancy was demonstrated by the X-ray photoelectron and electron spin resonance spectra. Compared with pure SnO2−x, g-C3N4 and stoichiometric SnO2/g-C3N4 composite, the optimum SnO2−x/g-C3N4 composite exhibited higher photoactivity for removing antibiotic (tetracycline hydrochloride) and organic dye (rhodamine B) under light-emitting diode (LED) track light irradiation. Furthermore, the optimum SnO2−x/g-C3N4 composite could completely inactivate Escherichia coli within 30 min. The remarkable performance of SnO2−x/g-C3N4 was mainly ascribed to oxygen vacancy: (i) enhanced the separation efficiency of photo-induced charge carriers between SnO2−x and g-C3N4; (ii) broadened light absorption range due to the formation of SnO2−x with narrow band gap. This work provides a new idea for designing g-C3N4-based photocatalyst with oxygen vacancy toward wastewater remediation. [ABSTRACT FROM AUTHOR]

It is still a great challenge to design efficient and stable photocatalysts to effectively remove organic pollution in water. A new type Bi 12 O 15 Cl 6 /SnO 2−x Z-scheme heterojunction was successfully constructed. The best sample 30% Bi 12 O 15 Cl 6 /SnO 2−x can degrade 86.7% TC within 90 min and 99.7% RhB within 75 min under LED light. The morphology, structure, optical and electrochemical properties of the photocatalyst were characterized by using different testing techniques. Efficient photoinduced charge transfer and separation efficiency was confirmed by photocurrent and electrochemical impedance spectra (EIS) in Bi 12 O 15 Cl 6 /SnO 2−x structure. The active substances, intermediate product and photodegradation pathway in degradation process were revealed by capture test and mass spectrometry (MS) measurement. In photocatalytic process, h+, •O 2 − and •OH are the main active species, and h+ is the most important active substance. In addition, the photocatalytic mechanism of charge separation is also proposed, which provides a new opportunity for the construction of photocatalysts and the degradation of organic pollutants in the water environment. • A novel Z-scheme Bi 12 O 15 Cl 6 /SnO 2−x heterojunction containing oxygen vacancy was prepared. • Degradation activity of Bi 12 O 15 Cl 6 /SnO 2−x on TC and RhB was significantly increased in LED light. • h+, •O 2 - and •OH are active species in photocatalytic process, and h+ is the main active substance. • The introduction of SnO 2−x enhances the transition of electrons and the absorption of light. • Z-scheme system promote the charge transfer and redox ability of Bi 12 O 15 Cl 6 /SnO 2−x. [ABSTRACT FROM AUTHOR]

The construction of heterojunction structure has been widely proved to be a general strategy for photocatalytic removal of pollutants. In this paper, a novel point and plane embedded SnO 2−x /Bi 4 O 5 I 2 heterojunction containing oxygen vacancy was synthesized by simple thermal decomposition of SnO 2−x /BiOI composite in a semi-closed crucible. The structure of SnO 2−x /Bi 4 O 5 I 2 was proved by TEM, HRTEM, BET, XPS and ESR. The SnO 2−x /Bi 4 O 5 I 2 catalyst successfully improved the photocatalytic performance in removing Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and tetracycline (TC), in contrast with individual SnO 2−x and Bi 4 O 5 I 2. Photocurrent and EIS results confirmed the high separation efficiency of electron and hole in composite. The active substance was identified by capture experiment, and combined with the energy band structure of the prepared photocatalyst, it was deduced that SnO 2−x /Bi 4 O 5 I 2 followed the double transfer mechanism. This study will furnish an efficient strategy to exploit tight heterojunction photocatalytic materials containing oxygen vacancy. Scheme: a novel point and plane embedding SnO 2−x /Bi 4 O 5 I 2 heterojunction containing oxygen vacancy was synthesized by simple thermal decomposition of SnO 2−x /BiOI composite in a semi-closed crucible. The composite showed good performance in removing E. coli , S. aureus and TC. The mechanism reveals that the photocatalytic process follows a double-charge mechanism, which is conducive to charge separation of electrons and holes. h+, e- and •OH are active species in the removing of E.coli , S. aureus and TC under LED light. [Display omitted] • Point and plane embedding SnO 2−x /Bi 4 O 5 I 2 is prepared by calcinating SnO 2−x /BiOI. • SnO 2−x /Bi 4 O 5 I 2 can effectively remove E. coli , S. aureus and TC under LED light. • A double-charge mechanism promoted the separation of photoexcited charges. • h+ is main active species for the photocatalytic process. [ABSTRACT FROM AUTHOR]

• A novel Z-scheme CQDs/g-C 3 N 4 /BiOBr was prepared. • CQDs/g-C 3 N 4 /BiOBr can effectively remove RhB, BPA, TC and E. coli under LED light. • h+, •O 2 - and •OH are all active substances in photocatalytic reactions. • Z-scheme in CQDs/g-C 3 N 4 /BiOBr produces a strong redox ability. • CQDs are favorable for transfer of charge carriers and light absorption ability. The photocatalytic mechanism was shown for Z-scheme CQDS/g-C 3 N 4 /BiOBr composite. h+, •O 2 - and •OH are all active substances in the removing of RhB, BPA, TC and inactivating E. coli under LED light. The addition of CQDs in the Z-scheme structure will promote the transition of electrons, enhance the absorption of light and improve the utilization rate of light absorption of the material. [Display omitted] To improve the photocatalytic performance, it is necessary to reduce the combination of photo-induced charges and improve the absorbance intensity of visible light. Herein, we have reported novel heterojunctions of indirect Z-scheme CQDs/g-C 3 N 4 /BiOBr composites (noted as CN@BOB-CQDs). Various techniques proved the successful preparation of heterojunction structure between CQDs, g-C 3 N 4 and BiOBr. Compared with g-C 3 N 4 and BiOBr, the composites presented excellent performance in removing Rhodamine B (RhB), bisphenol A (BPA) and tetracycline (TC) and E. coli by LED light illumination. The improvement of photocatalytic properties was assigned to its good separation efficiency of generated charges and strong redox ability of its photo-excited electrons (e) and holes (h+), which realized from the Z-type photo-excited charges transition in CN@BOB-CQDs composite. Besides, CQDs could promote the transmission of electrons and enhance the absorbance intensity of visible light. Finally based on the radicals' trapping experiments and the semiconductor energy band position, the photocatalytic mechanism on the degradation of RhB was illustrated. [ABSTRACT FROM AUTHOR]

The synthesized WO 3 /g-C 3 N 4 /BiOI photocatalyst followed a double S-scheme transfer process. The active species in the photocatalytic antibacterial process were h+, e−, OH and O2− under LED light. The double S-scheme structure promotes the separation efficiency of electron-hole pairs and increases the redox capacity of the heterojunction, which further improves the antibacterial performance for E. coli and S. aureus. [Display omitted] • Novel double S-scheme WO 3 /g-C 3 N 4 /BiOI photocatalyst was synthesized. • WO 3 /g-C 3 N 4 /BiOI can remove E. coli in 12 min and S. aureus in 20 min. • The active species are h+, e−, OH and O 2 −. • Double S-scheme promotes the electrons and holes separation. • Double S- scheme increases the redox capacity of the heterojunction. In recent years, the threat to human health from bacteria in wastewater has attracted attention, and photocatalytic technology has emerged as a promising strategy for inactivating bacteria in water. Therefore, it is of great research value to develop a novel high-efficiency photocatalytic system with the visible light response. We successfully designed a double S-scheme heterojunction composite WO 3 /g-C 3 N 4 /BiOI (WCB) in this paper. The preparation of WCB composites was demonstrated by a series of characterizations, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR) and transmission electron microscopy (TEM). The antibacterial effects of photocatalysts against representative Gram-negative strain Escherichia coli (E. coli) and Gram-positive strain Staphylococcus aureus (S. aureus) were tested under LED light irradiation. The novel photocatalyst presented excellent antibacterial properties, inactivating E. coli in 12 min and S. aureus in 20 min. The bacterial cell inactivation process was studied by scanning electron microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM). Active species capture experiments show that the active species present in the WCB composites in the process of inactivating bacteria are h+, e−, OH and O 2 −. In conclusion, the synthesized double S-scheme WCB photocatalyst exhibits remarkable photocatalytic antibacterial activity under LED light and has broad prospects for practical application in water antibacterial treatment. [ABSTRACT FROM AUTHOR]

The photocatalytic mechanism was shown for the novel BiO 2-x /BiOI photocatalyst. h+, •O 2 – and •OH are all active substances in removing RhB, MO, TC, E. coli and S. aureus under LED light. The introduction of oxygen defects and the construction of Z-scheme heterojunction extremely increase the performance of photocatalytic materials. [Display omitted] • Novel BiO 2-x /BiOI hybrid junction was prepared by a stirring route. • BiO 2-x /BiOI can effectively remove RhB, MO, TC, E. coli and S. aureus. • h+, •O 2 – and •OH are active substances in photocatalytic process. • Z-scheme in BiO 2-x /BiOI can induce a strong redox ability of electrons and holes. • The oxygen vacancies in BiO 2-x are conducive to the separation of photoexcited charges. Facing water pollution problems, developing a photocatalyst that can remove multiple pollutants with high redox ability is necessary. In this study, novel BiO 2-x /BiOI with Z-scheme heterojunction and oxygen vacancies was synthesized by room temperature stirring process. A series of techniques including TEM, Raman, XPS and ESR confirmed BiO 2-x /BiOI structure was successfully formed. Photocurrent, EIS impedance indicated the high separation efficiency of photogenerated electrons and holes between two semiconductors. The optimum sample 30% BiO 2-x /BiOI can degrade 96.4% rhodamine B (RhB), 88.7% methyl orange (MO) and 74.5% tetracycline (TC) within 90 min, respectively, and can inactivate 100% E. coli and S. aureus in 15 min and 20 min, respectively. These performance was realized under lower energy consumption light source (LED light), smaller amount of catalyst and shorter reaction time compared with related BiOI-based composites. The excellent photocatalytic performance was mainly attributed to the Z-scheme BiO 2-x /BiOI heterojunction with oxygen vacancy: (i) Z-scheme between BiO 2-x and BiOI can induce a strong redox ability of its photo-induced electrons and holes, (ii) the oxygen vacancies in BiO 2-x are conductive to the separation of photoexcited charges. This work offers a new example in improving the performance of composite semiconductor systems to be high and multiple efficiency photocatalyst. [ABSTRACT FROM AUTHOR]

The photocatalytic mechanism is shown for the novel BiOI/Bi 3 O 4 Cl photocatalyst. h+, •O 2 – and •OH are all active species, and h+ plays an important role in the removing of MO, BPA, TC and E.coli under LED light. The Fermi level reachs new equilibrium between p-type BiOI and n-Bi 3 O 4 Cl, which is favorable for the charge separation and enhancement of photoactivity. • New p-n BiOI/Bi 3 O 4 Cl hybrid junction was prepared by a facile ultrasonic route. • BiOI/Bi 3 O 4 Cl can effectively remove MO, BPA, TC and E.coli under LED light. • h+, •O 2 – and •OH are all active species, and h+ plays an important role. • The Fermi level reachs new equilibrium between p-type BiOI and n-Bi 3 O 4 Cl. • The p-n hybrid structure facilitates the separation of photoexcited charges. It is urgent to design highly efficient and broad-spectrum photocatalysts for wastewater treatment. In this work, a new p-n BiOI/Bi 3 O 4 Cl hybrid junction was prepared by a simple ultrasonication method. The optimal BiOI/Bi 3 O 4 Cl 30% composite could degrade 85.5% methyl orange in 90 min, 92.8% bisphenol A in 120 min and 73.5% antibiotic tetracycline in 180 min and thoroughly disinfect E. coli within 40 min. The results of transmission electron microscopy, photocurrent and electrochemical impedance spectrum confirmed the hybrid structure between BiOI and Bi 3 O 4 Cl, which promoted the separation of photoexcited electrons and holes in the semiconductor. Trapping experiments showed that holes (h+), superoxide anion radicals (•O 2 –) and hydroxyl radicals (•OH) were active species for photocatalytic reaction, and h+ played a more important role compared with •O 2 – and •OH. The mechanism revealed that the Fermi level reached new equilibrium between p-type BiOI and n-Bi 3 O 4 Cl, which is favorable for the charge separation and enhancement of photoactivity. The enlarged surface area of BiOI/Bi 3 O 4 Cl composite and efficient charge separation contributed to the enhanced photocatalytic performance. [ABSTRACT FROM AUTHOR]

Scheme: A novel narrow/wide band gap Bi 4 O 5 I 2 /BiOCl heterojunction was synthesized by a simple precipitation method. The composite showed good performance in removing E. coli , S. aureus and TC under LED light and sunlight. Under LED light, BiOCl as an electron-receiving platform promoted the separation of photoexcited charges. Under sunlight, Bi 4 O 5 I 2 /BiOCl follows a Z-scheme mechanism, •O 2 –, h+, e- and •OH are active species for the photocatalytic process. [Display omitted] • Novel narrow/wide band gap Bi 4 O 5 I 2 /BiOCl composite material was synthesized. • Bi 4 O 5 I 2 /BiOCl can remove E. coli , S. aureus and TC in LED light and sunlight. • In LED light, BiOCl acted as an electron-receiving platform. • In sunlight, Bi 4 O 5 I 2 /BiOCl follows a Z-scheme mechanism. • The performance of Bi 4 O 5 I 2 /BiOCl in sunlight is better than in LED light. It is necessary to construct photocatalytic heterojunctions with high efficiency to remove bacteria and antibiotics from polluted water. To achieve this goal, by selecting Bi 4 O 5 I 2 with narrow band gap and BiOCl with wide band gap, a novel Bi 4 O 5 I 2 /BiOCl heterojunction was constructed by a simple precipitation method. Various characterizations including XRD, TEM and XPS confirmed that the Bi 4 O 5 I 2 /BiOCl heterojunction was successfully synthesized. The optimum sample 30% Bi 4 O 5 I 2 /BiOCl can inactivate Escherichia coli (E. coli) in 30 min, Staphylococcus aureus (S. aureus) in 75 min and degrade 76% tetracycline (TC) in 60 min in LED light. To further study the performance of the photocatalyst, the photocatalyst was tested in sunlight. It was found 30% Bi 4 O 5 I 2 /BiOCl could inactivate E. coli in 6 min, S. aureus in 15 min and degrade 84% TC in 60 min under sunlight, realizing a shorter reaction time and a better degradation efficiency. Photocurrent and electrochemical impedance tests (EIS) results confirmed higher electron hole separation efficiency in composites. The mechanism of removing pollutants under LED light and sunlight was verified by their respective capture experiments. This experiment provides a new possibility for the application of photocatalysts in a variety of light sources. [ABSTRACT FROM AUTHOR]

Scheme: The proposed mechanism was presented for novel n-p type 0D/2D SnO 2−x /BiOI photocatalyst. The 0D SnO 2−x nanocrystals combine with 2D BiOI nanosheet to form a close n-p hybrid junction. Fermi level reached new equilibrium between SnO 2−x and BiOI, which is conductive to the separation of electrons and holes and the improvement of photocatalytic performance. h+, •O 2 − and •OH are active species in the removing of tetracycline, E. coli and S. aureus under LED light. • 0D/2D SnO 2−x /BiOI has high specific surface area. • SnO 2−x /BiOI can effectively remove TC, E. coli and S. aureus under LED light. • n-p hybrid structure facilitates the separation and transfer of photoexcited charges. • h+, •O 2 − and •OH are active species for the photocatalytic process. The construction of efficient and multifunctional photocatalyst with tight hybridization structure is an ideal method to remove pollutants from wastewater. To achieve the goal, a novel n-p type 0D/2D SnO 2−x /BiOI photocatalyst was prepared by using large specific surface area SnO 2− x (203.1 m2/g) combining with BiOI nanosheet through a facile in situ growth route. A series of techniques including TEM, HRTEM and BET confirmed the structure of 0D/2D SnO 2−x /BiOI composite. As expected, the novel SnO 2−x /BiOI photocatalyst can successfully remove tetracycline (TC), Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) under LED light. Photocurrent and EIS verified the enhanced separation efficiency of photo-excited electron-hole pairs. Trapping experiment and mass spectrometry analysis revealed the active species, intermediate product and photodegradation pathway in photocatalytic process. The mechanism reveals that the Fermi levels of n-type SnO 2−x and p-type BiOI have reached a new equilibrium, which is conducive to charge separation of electrons and holes. This work provides an effective example for the preparation of compact heterojunction photocatalytic materials with high efficiency. [ABSTRACT FROM AUTHOR]

Novel carbon quantum dots/1D MoO 3-x hybrid junction (noted as CQDs/MoO 3-x) was obtained by a facile hydrothermal route. The CQDs/MoO 3-x photocatalyst was estimated as an effective photocatalyst for inactivating E. coli and S. aureus under LED light. Compared with pure MoO 3 and MoO 3-x , CQDs/MoO 3-x photocatalyst displayed better performance in inactivating E. coli and S. aureus. The results of UV–visible diffuse reflectance spectrum (UV–vis DRS), transmission electron microscopy (TEM) and electrochemical impedance spectrum (EIS) indicated the enhanced photoactivity is ascribed to: (1) MoO 3-x has good absorption property of visible light; (2) the 1D structure of MoO 3-x prolongs the lifetime of photo-excited charge carriers; (3) CQDs modifying 1D MoO 3-x is not only favorable for absorption of visible light, but also for the fast transport and surface separation of the charge carriers. The capture experiment showed that holes (h+) are main active species in the photocatalytic process. This work presents an efficient photocatalyst for water antibacterial treatment. • Novel carbon quantum dots/1D MoO 3-x photocatalyst was successfully prepared. • The hybrid catalyst can inactivate E.coli and S. aureus under LED light. • Holes are main active species in the photocatalytic processing. • CQDs and 1D MoO 3-x are both favorable for the improved photocatalytic activity. [ABSTRACT FROM AUTHOR]

A novel β-Bi 2 O 3 @BiOBr core/shell photocatalyst was successfully designed by a facile ultrasonication method. The β-Bi 2 O 3 @BiOBr photocatalyst showed better photocatalytic antibacterial activity than pure β-Bi 2 O 3 and BiOBr under LED light. β-Bi 2 O 3 @BiOBr photocatalyst can completely inactivate Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) within 50 min. The enhanced photoactivity is due to a hybrid structure of BiOBr and β-Bi 2 O 3 , which led to an efficient separation of electron (e−) and hole (h+) pairs between the semiconductors. Moreover, the trapping experiment confirmed that h+ played an important role in the photocatalytic process. The present work provided a novel LED light-activated photocatalyst that was promising for water treatment. • Novel β-Bi 2 O 3 @BiOBr core/shell composite was prepared by a facile ultrasonic route. • β-Bi 2 O 3 @BiOBr can effectively inactivate E.coli and S. aureus under LED light. • Holes are main active species in the photocatalytic processing. • Dual charge transfer mechanism was proposed for photocatalytic process. [ABSTRACT FROM AUTHOR]

GO/CN/BiOI composites were obtained by in-situ generation route and investigated in photocatalytic degradation and antibacterial. Detailed analysis of the photocatalyst was presented by XRD, TEM, SEM, XPS, FT-IR, Raman, DRS, photocurrent, EIS and LSCM. The synthesized GO/CN/BiOI composites showed good photocatalytic degradation and excellent antibacterial performance under LED light. The optimal composite could degrade 93% methyl orange (MO) in 60 min and 74% tetracycline (TC) in 100 min. In terms of antibacterial, GO/CN/BiOI composites could completely inactivated E. coli and S. aureus within 30 min. The mechanism of photocatalytic degradation and antibacterial activity was studied by trapping experiments, and h+ played an important role in the system. The improved photo-performance was attributed to the efficient separation of electrons (e−) and holes (h+) in the composite. This work showed the GO/CN/BiOI composite is a potential photocatalyst in pollution removing and water disinfection. • GO/CN/BiOI composites were prepared by one step in-situ generation method. • GO/CN/BiOI composites can remove MO, TC, E. coli , S. aureus under LED light. • The introduction of GO is beneficial to the improvement of photocatalytic performance. • GO-assisted double-charge-transfer mechanism was presented. [ABSTRACT FROM AUTHOR]

Novel Ag/SnO 2-x /Bi 4 O 5 I 2 ternary composites were prepared by introducing Ag nanoparticles in SnO 2-x /Bi 4 O 5 I 2 binary composites. Ag nanoparticles as an electron transport bridge is beneficial to the separation of photocarriers. The noble metal surface plasmon resonance (SPR) effect of Ag nanoparticles can also enhance the visible light absorption performance of the composites. 3% Ag/SnO 2-x /Bi 4 O 5 I 2 can degrade 80% TC in 120 min, inactivate E. coil in 15 min and S. aureus in 20 min. [Display omitted] • A novel Z-scheme Ag/SnO 2-x /Bi 4 O 5 I 2 ternary composite was prepared. • Ag/SnO 2-x /Bi 4 O 5 I 2 can effectively remove E. coli , S. aureus and TC under LED light. • h+, e- and •OH are main active species. • Ag nanoparticles are in favor of the separation of carriers and light absorption. • Z-scheme in the composite promoted the separation of charges and its redox ability. Ag/SnO 2-x /Bi 4 O 5 I 2 ternary composites were prepared to further improve the photocatalytic properties by introducing Ag nanoparticles into SnO 2-x /Bi 4 O 5 I 2 binary composites. X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) proved that the ternary composites were successfully synthesized. Photocurrent and electrochemical impedance tests (EIS) confirmed that the photogenerated carrier separation efficiency of Ag/SnO 2-x /Bi 4 O 5 I 2 was much higher than SnO 2-x and Bi 4 O 5 I 2. Ag/SnO 2-x /Bi 4 O 5 I 2 showed high efficiency in degradation and antibacterial. The optimum sample of 3% Ag/SnO 2-x /Bi 4 O 5 I 2 can degrade 80 % tetracycline (TC) in 120 min, inactivate Escherichia coli (E. coil) in 15 min and Staphylococcus aureus (S. aureus) in 20 min under the LED light. The intermediates of the degradation of TC were identified by mass spectrometry (MS). Scanning electron microscopy (SEM) and confocal laser scanning microscope (CLSM) images intuitively showed the death process of E. coil caused by the photocatalytic reaction. The results of the capture experiment identified the active substance, and the possible photocatalytic degradation pathway was proposed. Ag/SnO 2-x /Bi 4 O 5 I 2 followed the Z-scheme charge transfer mechanism. [ABSTRACT FROM AUTHOR]

To remove multitudinous pollutants from wastewater, the design of a highly efficient and multifunctional photocatalyst is necessary. A novel CQDs/SnO 2-x /BiOI photocatalyst (named CSnBI composite) was prepared by combining carbon quantum dots (CQDs), large specific surface area SnO 2-x nanocrystals and BiOI nanocrystals to obtain a compact hybrid structure. TEM and Raman techniques confirmed the structure of CSnBI composite. The photocurrent and EIS showed that the photoexcited electron-hole pairs separation efficiency was improved. As anticipated, novel CSnBI photocatalyst can successfully remove tetracycline, methyl orange, E. coli (Escherichia coli) and S. aureus under a LED light due to the hybridization contaction among CQDs, SnO 2-x and BiOI. The mechanism showed that the introduction of CQDs promoted visible light absorption and efficient separation of photogenerated carriers of SnO 2-x /BiOI heterojunction. The capture experiment and related measurements showed that h+, •O 2 − and •OH are active species in the photocatalytic process. This study gave a novel case for facile construction of photocatalysts with tight hybrid structure. • Novel CQDs decorated SnO 2-x /BiOI hybrid structure was synthesized. • Under LED light CQDs/SnO 2-x /BiOI successfully remove MO, TC, E. coli and S. aureus. • In photocatalytic reactions, h+,•O 2 − and •OH are active species. • SnO 2-x /BiOI hybrid promoted the separation and transfer of charges effectively. • CQDs are favorable for the transfer of charge carriers and light absorption ability. [ABSTRACT FROM AUTHOR]