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In the study, AgBr nano-cakes decorated Ti 3+ self-doped TiO 2 nanorods/nanosheets (AgBr-Ti 3+ /TiO 2 NRs/NSs) photoelectrode with enhanced visible light driven photocatalytic (PC) and photoelectrochemical (PECH) performance has been successfully fabricated by hydrothermal reaction, followed by sodium borohydride reduction and then successive ionic layer adsorption and reaction (SILAR) treatment. Afterwards, series of characterizations were conducted to study the physicochemical properties of AgBr-Ti 3+ /TiO 2 NRs/NSs photoelectrode. Results indicated that AgBr nano-cakes with sizes varying from 110 to 180 nm were uniformly decorated on the surface of Ti 3+ /TiO 2 NRs/NSs to form AgBr-Ti 3+ /TiO 2 NRs/NSs photoelectrode. Moreover, PC activity of AgBr-Ti 3+ /TiO 2 NRs/NSs photoelectrode was measured by degradation of methylene blue (MB). It was found that AgBr-Ti 3+ /TiO 2 NRs/NSs photoelectrode exhibited higher PC activity (98.7%) than that of other samples within 150 min visible light illumination, owing to the enhancement of visible light harvesting and effective separation of photoproduced charges. Thus, AgBr nano-cakes and Ti 3+ exerted a huge influence on the PC and PECH properties of AgBr-Ti 3+ /TiO 2 NRs/NSs photoelectrode. Furthermore, the possible enhanced visible light driven PC mechanism of AgBr-Ti 3+ /TiO 2 NRs/NSs was proposed and confirmed. [ABSTRACT FROM AUTHOR]

In the research, reduced TiO 2 nano-tube arrays (denoted as R-TiO 2 NTAs) photoelectrode was successfully fabricated by potassium borohydride (PBH) reduction treatment. Afterwards, the as-fabricated photoelectrode was characterized by scanning electron microscope, X-ray diffraction, Raman spectra and electron spin resonance. Meanwhile, the optical and photoelectrochemical properties of R-TiO 2 NTAs photoelectrode were also studied through ultraviolet-visible diffuse reflectance spectroscopy and transient photocurrent response, respectively. The photocatalytic (PC) activity of R-TiO 2 NTAs photoelectrode was measured by degradation of trichlorophenol (TCP). Moreover, the change of toxic intermediates in the process of degradation TCP was further evaluated by photobacterium inhibition tests. Results suggested that an impurity level can be induced in the TiO 2 NTAs band gap by solution reduction treatment due to the generation of Ti 3+ and oxygen vacancies (Ov). Furthermore, R-TiO 2 NTAs photoelectrode exhibited higher PC activities than that of pristine TiO 2 NTAs owing to the enhancement of visible light harvesting between 450 and 800 nm and separation efficiency of photogenerated electrons-holes (e/h + ) pairs. The possible pathway for TCP degradation and photocatalytic mechanism were also proposed and confirmed. Furthermore, R-TiO 2 NTAs photoelectrode displayed good stability and reusability. [ABSTRACT FROM AUTHOR]

In the study, visible-light active Ti 3+ doped TiO 2 nanorods/nanosheets (Ti 3+ /TiO 2 NRs/NSs) photoelectrode was successfully fabricated by hydrothermal reaction, followed by sodium borohydride reduction treatment. Moreover, physicochemical properties of the resulting samples were studied by series of techniques. Also, photocatalytic (PC) activity of Ti 3+ /TiO 2 NRs/NSs photoelectrode was measured by degradation of methylene blue (MB). Results suggested that Ti 3+ and oxygen vacancies (Ov) were simultaneously formed and induce the formation of impurity energy level in the TiO 2 NRs/NSs band gap by solution reduction treatment, which exerted a huge influence on the photocatalytic and photoelectrochemical properties of Ti 3+ /TiO 2 NRs/NSs photoelectrode in the mean time. Furthermore, Ti 3+ /TiO 2 NRs/NSs photoelectrode exhibited higher PC activity (89.61%) than that of pristine TiO 2 NRs/NSs (73.56%) within 150 min visible light illumination owing to the enhancement of visible light harvesting and separation efficiency of photoproduced charges. Moreover, the possible enhanced PC mechanism of Ti 3+ /TiO 2 NRs/NSs was proposed and confirmed. Furthermore, Ti 3+ /TiO 2 NRs/NSs photoelectrode displayed good stability and reusability. [ABSTRACT FROM AUTHOR]

In the present study, silver phosphate/graphene oxide (Ag 3 PO 4 /GO) composite was synthesized by ultrasound-precipitation processes. Afterwards, physicochemical properties of the resulting samples were studied through scanning electron microscope, transmission electron microscope, X-ray diffraction, N 2 adsorption/desorption, UV–vis diffuse reflectance spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, surface photovoltage spectroscopy and photoelectrochemical measurements. Results indicated that spherical Ag 3 PO 4 displayed an average diameter of 150 nm and body-centered cubic crystal phase, which was integrated with GO. In addition, the visible light absorbance, charge separation efficiency and lifetime of Ag 3 PO 4 were significantly improved by integration with GO. In addition, Ag 3 PO 4 /GO composite was applied to decompose tetrabromosphenol A (TBBPA) in water body. It was found that TBBPA could be completely decomposed within 60 min illumination. Furthermore, several scavenger experiments were conducted to distinguish the contribution of reactive species to the photoctalytic efficiency. Moreover, the enhanced visible light mechanism of Ag 3 PO 4 /GO was proposed and discussed. Eventually, several PC decomposition pathways of TBBPA were identified including directly debromination and oxidation, and subsequently further oxidation and hydroxylation processes. [ABSTRACT FROM AUTHOR]

In the present work, plasmonic Ag/AgBr nano-particle was fabricated by solution reduction strategy. Meanwhile, physicochemical properties of the resulting samples were investigated by series of techniques. Results showed that Ag/AgBr nano-particle exhibited intense light absorbance in the whole visible region, high photoinduced charge separation efficiency and visible light driven PC performance. Furthermore, the enhanced visible light PC mechanism was proposed and confirmed. Besides, the PC degradation pathways of acetaminophen were elucidated based on the UPLC-MS/MS measurement. Results indicated that five degradation intermediates were detected, consequently two tentative pathways for PC degradation of acetaminophen were proposed, for example hydroxylation addition to parent compound and C N cleavage of side chain from the acetaminophen attacked by photoinduced holes. This study provides a facile and feasible strategy to fabricate high-efficient visible light response of nano-materials which can be applied in the fields of waste water treatment. [ABSTRACT FROM AUTHOR]

In the study, we report that p-type NiO (p-NiO) nanoparticles were successfully decorated onto the surface of n-type TiO 2 nano-tube arrays (n-TiO 2 NTAs) photoelectrode by anodization process, followed by electrodeposition strategy in the presence of NiSO 4 electrolyte. After then, the samples were studied by scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). In addition, the optical and photoelectrochemical (PECH) properties of p-NiO/n-TiO 2 NTAs were recorded through ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS), open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) curves, respectively. Furthermore, We evaluated the photocatalytic (PC) degradation of 4-chlorphenol and the enhanced PC mechanism was also discussed. Results suggest that p-NiO/n-TiO 2 NTAs photoelectrode exhibited higher PC activities than that of pristine TiO 2 NTAs owing to its higher photogeneration electrons-holes (e/h + ) pairs separation efficiency and light absorbance. As a consequence, the p-NiO/n-TiO 2 NTAs photoelectrode could be applied in degradation of organic pollutants and wastewater purification. [ABSTRACT FROM AUTHOR]

In order to improve the photocatalytic (PC) performance of TiO 2 nano-material, TiO 2 nanotube arrays (NTAs) was fabricated by anodization. Subsequently, Bi 2 O 3 nano-particles were successfully deposited onto the surface of TiO 2 NTAs through galvanostatic electrodeposition strategy. Afterwards, series of characterizations including scanning electron microscope (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS) and photoelectrochemical (PECH) measurements were applied to clarify physicochemical properties of the as-fabricated Bi 2 O 3 /TiO 2 NTAs photoelectrode. All results indicated that the light absorbance and photoinduced charge separation efficiency of Bi 2 O 3 /TiO 2 NTAs photoelectrode were significantly improved. As expected, Bi 2 O 3 /TiO 2 NTAs photoelectrode displayed higher PC efficiency for degradation of 4-chlorphenol (4-CP) aqueous solution than that of pristine TiO 2 NTAs. Besides these, the enhanced visible light PC mechanism was proposed. Furthermore, Bi 2 O 3 /TiO 2 NTAs photoelectrode performed good reusability and stability even after six recycle utilization. [ABSTRACT FROM AUTHOR]

• Bi 2 O 3 /CuNiFe LDHs was employed to activate persulfate (PS) under simulated sunlight. • A synergistic effect between photochemical and catalytic processes was achieved. • Several reaction pathways and the mechanism of LOM degradation were proposed. • Bi 2 O 3 /CuNiFe LDHs exhibited good reusability and high stability at natural pH. Advanced oxidation methods based on photocatalysis and sulfate radicals have attached most interest towards contaminant degradation. However, there are a lack of coupling two methods in the field of pollutant degradation. In the present study, a new Bi 2 O 3 /CuNiFe LDHs composite was fabricated and it could efficiently activate persulfate (PS) for lomefloxacin (LOM) decomposition under simulated sunlight, in which 84.6% of LOM (10 mg·L−1) was degraded over 40 min with 0.4 g·L−1 of Bi 2 O 3 /CuNiFe LDHs composite and 0.74 mM of PS at natural pH. In addition, the Bi 2 O 3 /CuNiFe LDHs composite possessed good reusability and stability at least four runs. Moreover, active radical scavenging experiments indicated that hydroxyl radicals (HO·), sulfate radicals (SO 4 ·−), superoxide radicals (O 2 ·−) and hole (h+) were the main radicals under LOM degradation process. Subsequently, the possible degradation intermediates were determined and the decomposition pathways were put forward. At the same time, activated sludge inhibition experiments were performed to assess the variation of toxicity of LOM and its degradation intermediates during oxidation. Finally, possible reaction mechanism of Bi 2 O 3 /CuNiFe LDHs composite for PS activation under simulated sunlight was proposed. [ABSTRACT FROM AUTHOR]

• PbS/TiO 2 NTs was fabricated by successive ionic layer adsorption and reaction strategy. • PbS/TiO 2 NTs exhibited superior charge separation efficiency and high PC activity. • PbS/TiO 2 NTs displayed high photoelectrochemical properties. • The enhanced visible PC mechanism of PbS/TiO 2 NTs was proposed. In this study, highly ordered TiO 2 nano-tubes (TiO 2 NTs) were synthesized by anodization. Subsequently, PbS nanoparticles were successfully decorated onto the surface of TiO 2 NTs by successive ionic layer adsorption and reaction strategy in the presence of lead acetate (Pb(Ac) 2) and thiourea. Afterwards, morphologies and chemical structures of PbS/TiO 2 NTs photoelectrode were systematically studied by scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Results showed that PbS nanoparticles were uniformly dispersed on the surface of TiO 2 NTs, and a small amount of PbS nanoparticles gathered together. Besides, their optical properties were investigated by ultraviolet–visible diffuse reflectance spectroscopy (DRS), transient photocurrent density, open potentials, electrochemical impedance spectroscopy (EIS) and Mott-schottky measurements. Compared with the pristine TiO 2 NTs photoelectrode that only could utilize ultraviolet light, The PbS/TiO 2 NTs photoelectrode presented absorption properties of visible light, which improved the utilization of solar energy. What's more, the photocatalytic degradation performance of PbS/TiO 2 NTs photoelectrode was studied by using 4-chlorobenzoic acid as the target pollutant, finding that 80.37% of 4-chlorobenzoic acid could be removed within 7 h. After these, based on the electrochemical and fluorescence spectra, the enhanced photocatalytic performance mechanism of PbS/TiO 2 NTs was proposed. In addition, the PbS/TiO 2 NTs possessed excellent stability for 4-chlorobenzoic acid degradation after consecutive utilization for five cycles. This study illustrated that the novel PbS/TiO 2 NTs photoelectrode was a promising photocatalyst with many potential applications, which could be used in sewage treatment process. Most importantly, this study provided a theoretical support for the practical application of photocatalytic technology. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A novel visible-light-driven BiOCOOH/g-C 3 N 4 photocatalyst was synthesized. • BiOCOOH/g-C 3 N 4 photocatalyst exhibited high physicochemical properties. • BiOCOOH/g-C 3 N 4 photocatalyst displayed superior photocatalytic performance. • The enhanced visible light photocatalytic mechanism was proposed. Abstract The application of semiconductor photocatalysts in wastewater treatment has received increasingly attentions because of its potential utilization of solar energy. In this study, a novel visible-light-driven (VLD) BiOCOOH/g-C 3 N 4 composite photocatalyst was successful synthesized by a facile hydrothermal method. Afterwards, physicochemical properties of the resulting samples were investigated through X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) surface areas, UV–visible diffuse reflectance spectroscopy (UV–vis DRS), transient photocurrent density, Mott-Schottky (M−S) and electrochemical impedance spectroscopy (EIS) measurement. Furthermore, the visible light photocatalytic (PC) performance was evaluated through the degradation of amido black 10B dye. All results indicated that the combination of g-C 3 N 4 and BiOCOOH could exhibited greatly visible light absorbance and photo-generated charge separation efficiency, thereby resulting in the enhanced PC performance of BiOCOOH/g-C 3 N 4 composite photocatalyst. The optimal Bi/C molar rate in BiOCOOH/g-C 3 N 4 composite was determined to be 1/1, and the corresponding photodegradation rate for amido black 10B was 0.01794 min−1, which was nearly 2.19 and 5.73 folds higher than that of pure g-C3N4 and BiOCOOH. The possible mechanism of the PC reaction was also discussed in detail. Furthermore, BiOCOOH/g-C 3 N 4 composite photocatalyst performed good reusability and stability even after four recycle utilization. [ABSTRACT FROM AUTHOR]

There is an increasingly significant issue on decomposition of contaminants in modern chemical industry and environmental protection. Hence, in the study, to improve the catalytic of semiconductor materials, the silver-silver bromide nanoparticles decorated reduced TiO 2 nano-tube arrays photoelectrode (Ag-AgBr/r-TiO 2 NTAs), which exhibits better photocatalytic (PC) performance in the wide range of solar spectra, was successfully fabricated by anodization process, followed by microwave reduction strategy. The partly reduced AgBr nanoparticles are decorated and both Ti 3+ and O v states are simultaneously introduced in the TiO 2 NTAs photoelectrode inducing the formation of impurity energy level to form Ag-AgBr/r-TiO 2 NTAs photoelectrode. Moreover, PC activity of Ag-AgBr/r-TiO 2 NTAs photoelelctrode was measured by degradation of 4-chlorphenol (4-CP). Results suggest that Ag-AgBr/r-TiO 2 NTAs photoelectrode exhibits higher PC activity (99.9%) than that of other samples within 120 min illumination. The well combination of surface plasmons Ag-AgBr nanoparticles and r-TiO 2 NTAs was responsible for the enhancing of PC, and the recombination of photo-generated electrons and holes can simultaneously be inhibited. Thus, Ag-AgBr nanoparticles and Ti 3+ exert huge influence on the PC and photoelectrochemical properties of Ag-AgBr/r-TiO 2 NTAs photoelectrode. [ABSTRACT FROM AUTHOR]

To improve the photocatalytic (PC) performance of g-C 3 N 4 nano-material, a novel Z-scheme Bi 2 O 3 /g-C 3 N 4 composite photocatalyst was synthesized by heat treatment method. Subsequently, the morphologies, chemical structures, optical and photoelectrochemical (PECH) properties of as-obtained photocatalysts were investigated through X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) surface areas, UV–visible diffuse reflectance spectroscopy (UV–vis DRS), transient photocurrent density, Mott-Schottky (M-S) and electrochemical impedance spectroscopy (EIS) measurement. Furthermore, the PC efficiency was evaluated by degradation of amido black 10B dye. All results indicated that as-fabricated Bi 2 O 3 /g-C 3 N 4 photocatalytic system displayed superior PC performance under visible light illumination, which was mainly ascribed to the intense visible light absorbance and the migration of photo-generated carriers adopted a Z-scheme mechanism. Moreover, the degradation of amido black 10B for 3 wt.%Bi 2 O 3 /g-C 3 N 4 were about 1.41 and 1.42 times than that of pure g-C 3 N 4 and pure Bi 2 O 3 , respectively. [ABSTRACT FROM AUTHOR]

This work shows results of our investigation on Ag 3 PO 4 /TiO 2 NTAs photoelectrode photodegradation properties to diclofenac with visible light illumination. The composite photoelectrode has been synthesized by ultrasound-precipitation strategy and characterized through scanning electrons microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). In addition, photoelectrochemical and visible photocatalytic activity properties of as-prepared samples were investigated to prove the fact. Compared with pure TiO 2 NTAs, Ag 3 PO 4 /TiO 2 NTAs photoelectrode possesses the enhancement of light absorbance in the visible region and a lower recombination rate of photogenerated electron–hole pairs, so that it performed a better visible light photocatalytic property. Additionally, prepared Ag 3 PO 4 /TiO 2 NTAs photoelectrode has well recyclability. On the basis of electrochemical, fluorescence spectra and photoluminescence, the photocatalytic performance enhancement mechanism for Ag 3 PO 4 /TiO 2 NTAs was put forward. [ABSTRACT FROM AUTHOR]

In order to improve the charge separation and photocatalytic (PC) efficiency of TiO 2 nano-tube arrays (TiO 2 NTAs) photoelectrode, narrower band gap Ag 2 O nano-crystallites decorated reduced TiO 2 NTAs (Ag 2 O/r-TiO 2 NTAs) photoelectrode was fabricated through one-step microwave reduction strategy, which could simultaneously induce the generation of Ag 2 O nano-crystallites onto the surface of TiO 2 NTAs and Ti 3+ self-doping energy level below the conduction band of TiO 2 . Subsequently, the resulting photoelectrodes were systematically studied by scanning electron spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV–visible light diffuse reflectance spectroscopy and photoelectrochemical measurements. In addition, the photocatalytic (PC) performance was evaluated by photodecomposition of methyl blue and generation of OH radicals. As a result, Ag 2 O/r-TiO 2 NTAs photoelectrode performed a significantly enhanced light absorbance in the whole visible region, transient photocurrent density of 0.189 mA cm −2 , photoinduced charge separation efficiency and 98.9% of PC efficiency for decomposition of methyl blue. Furthermore, the enhanced visible light PC mechanism for decomposition of organic pollutant was proposed, which was mainly attributed to the strong visible light absorbance and high photoinduced charge separation efficiency. Moreover, the as-fabricated Ag 2 O/r-TiO 2 NTAs photoelectrode performed well stability after consecutive utilization for five cycles. This study provides a versatile strategy to fabricate high-efficient catalyst which could be utilized in waste water elimination. [ABSTRACT FROM AUTHOR]

Norfloxacin, as an antimicrobial drug, has frequently been detected in municipal plants, which is predicted to be potential risk on human beings and the environment. In the present study, zeolite immobilizes silver oxide decorated titanium dioxide (Ag 2 O/TiO 2 -Zeolite) composite has been fabricated through modified sol-gel method. Afterwards, physicochemical properties of the as-fabricated Ag 2 O/TiO 2 -Zeolite sample are systematically studied by scanning electron microscope, X-ray diffraction, X-ray photoelectron microscopy, ultraviolet visible diffuse reflectance spectroscopy and surface photovoltage spectra measurements. Besides these, photocatalytic (PC) performance of Ag 2 O/TiO 2 -Zeolite composite is evaluated by photodecomposition of norfloxacin under simulated solar light illumination and generation of active hydroxyl ( OH) radicals. Results indicate that the decorated Ag species exists in the form of Ag 2 O, which can greatly enhance the visible light absorbance and charge separation efficiency. Furthermore, Ag 2 O/TiO 2 -Zeolite composite displays superior PC performance, which is mainly ascribed to the intense light absorbance in visible region, narrow band gap level and high charge separation efficiency. In addition, the solar light PC degradation pathways of norfloxacin are proposed according to the HPLC-MS/MS measurements, including hydroxylation addition to parent compound, decarboxylation and defluorination of side chain from the norfloxacin. Moreover, the as-fabricated Ag 2 O/TiO 2 -Zeolite composite exhibits high stability after consecutive utilization for seven times. [ABSTRACT FROM AUTHOR]