Search query: Facile solvothermal synthesis of a Z-Scheme

Related papers:

abstract: Abstract Reasonable designing heterojunction photocatalysts is an effective way to improve the photocatalytic activity of semiconductor. Herein, the efficient binary heterojunction photocatalyst formed between zero dimensional (0D) CeO2 nanoparticles and three dimensional (3D) floriated shaped ZnIn2S4 microspheres was synthesized by a simple solvothermal method. A series of analytical methods were used to characterize the optical properties and morphology of CeO2/ZnIn2S4 composite photocatalysts. Photodegradation experimental results showed that CeO2/ZnIn2S4 composites displayed strong photocatalytic activity for the degradation of tetracycline (TC) with heavy concentrations (30 mg/L) The as obtained optimum 10 wt% CeO2/ZnIn2S4 sample displays high degradation efficiency of 91% within 120 min, which is about 12.9 and 3.03 times higher than that of pure CeO2 and ZnIn2S4, respectively. The enhanced photocatalytic activity is ascribed to the formation of Z scheme heterojunction between CeO2 and ZnIn2S4, which contributes to the increased surface area, enhanced redox ability and high separation efficiency of photogenerated charge carriers. The degradation pathways and intermediate products of TC over CeO2/ZnIn2S4 composite were analyzed by liquid chromatography mass spectrometry (LC/MS) measurement. This study provides a new approach to prepare of efficient 0D/3D based Z scheme heterojunction photocatalysts.
author_names: Chen Hao

Yu-bin Tang

Weilong Shi

Fang-yan Chen

Feng Guo
title: Facile solvothermal synthesis of a Z Scheme 0D/3D CeO2/ZnIn2S4 heterojunction with enhanced photocatalytic performance under visible light irradiation
year: 2021

abstract: Abstract In present study, polyaniline/bismuth bromide/zinc ferrite (PANI/BiOBr/ZnFe2O4) was rationally designed and successfully prepared via a facile hydrothermal synthesis method. The crystal structure, chemical composition and morphology of the samples were analyzed by various characterization techniques. The PANI/BiOBr/ZnFe2O4 composite exhibits a higher photocatalytic activity compared with other samples under visible light irradiation. Among all samples, the highest degradation efficiency for RhB over 7% PANI/BiOBr/ZnFe2O4 reach 99.26% Meanwhile, the composite exhibits an excellent catalytic activity for the reduction of nitrobenzene (NB) under visible light, the conversion efficiency can reach 87.1% Moreover, the ternary composite still maintains a higher photocatalytic activity after three consecutive uses. Additionally, according to PL spectra and electrochemical impedance spectroscopy (EIS) the improved photocatalytic performance of PANI/BiOBr/ZnFe2O4 composite can be attributed to the rapid separation and transfer of electron hole pairs. Finally, the dual Z scheme electron transfer mechanism suitable for this system was proposed by UV vis DRS spectra, M S curves analysis, ESR spectra and free radical capture experiments. This study provides a new research idea for the design and construction of efficient photocatalysts for organic pollutants and other water treatment problems.
author_names: Rui Zhang

Qiong Han

Yu Li

Tongqing Zhang

Yu-qiong Liu

Kunlin Zeng

Chen Zhao
title: Solvothermal synthesis of a peony flower like dual Z scheme PANI/BiOBr/ZnFe2O4 photocatalyst with excellent photocatalytic redox activity for organic pollutant under visible light
year: 2020

abstract: Abstract The Bi based hierarchical multi component photocatalytic system is an important player in energy and environmental catalysis due to its full spectrum light absorption and stable separation of photo generated charges. In this study, a novel family of iodine doped Bi2O2CO3/Bi2WO6 heterojunctions was successfully developed by a facile ionic liquid assisted solvothermal method. A visible light photocatalytic H2 production rate of 664.5 mmol g 1 h 1 (0.3I Bi2O2CO3/Bi2WO6 with 3% Pt) has been durably obtained, much higher than those of pristine and undoped counterparts. The photocatalysts are also capable for persistent pollutant and dye degradation. Through electrochemical and spectroscopic tests and density functional theory calculation, the enhanced photocatalytic activity is attributed to formation of the Z scheme photocatalyst. Therein, the lowered and indirect bandgap and heterojunctional band alignment spontaneously benefit visible light harvesting, electron hole pair separation, and proton reduction. Besides a facile synthesis for effective photocatalysis, the Z scheme mechanism is hoped to facilitate the design and realization of similar systems for photocatalytic H2 evolution and organic hazards decontamination.
author_names: Zhuomin Qiang

Ximeng Liu

Feng Li

Taihai Li

Meng Zhang

Harishchandra Singh

Marko Huttula

Wei Cao
title: Iodine doped Z scheme Bi2O2CO3/Bi2WO6 photocatalysts: Facile synthesis, efficient visible light photocatalysis, and photocatalytic mechanism
year: 2021

abstract: Abstract Novel Z scheme W18O49 nanowire g C3N4 nanosheet composite photocatalysts were prepared by a facile solvothermal process. The morphology of W18O49 nanocrystals was significantly changed from urchin sphere to nanowire bundles with the increase of C3N4 quantity. The W18O49 g C3N4 composites enhance the ability of harvesting visible light, and promote the charge transfer across the composite interface. All the as prepared composites show higher photocatalytic activity of hydrogen production than that of pure W18O49 and g C3N4. And the WCN50 composite with 50 mg of g C3N4 displays the optimal photocatalytic activity with the highest hydrogen production rate of 1.700 mmol g 1 h 1under visible light irradiation. The improved photocatalytic activity is due to the stronger light harvesting ability, the Z scheme charge transfer mechanism to promote the interface charge transfer, and the prolonged lifetime of photogenerated electrons. Our work will provide a valuable reference for the design of highly efficient Z scheme photocatalysts for efficiently converting solar energy into chemical fuels.
author_names: Zhang Jinhong

Jincheng Liu

Zhao Wei

Ding Zhongxiang

Jijin Mai

Yanxiong Fang
title: Facile synthesis of high quality Z scheme W18O49 nanowire g C3N4 photocatalyst for the enhanced visible light driven photocatalytic hydrogen evolution
year: 2018

abstract: Bi2O2CO3 based ternary composite materials are generally synthesized by two or multi step method and special precursor of CO32 is usually utilized in synthesis of Bi2O2CO3, which are time consuming, laborious and relatively costly. In this paper, for the first time, a facile one step solvothermal method is used to fabricate Z scheme Bi2O2CO3/Bi/Bi2WO6 ternary composites. Interestingly, ethylene glycol not only acts as solvent for the reaction system, but also reduced Bi3+ into metallic Bi and itself is oxidized to CO32 which could construct Bi2O2CO3. On this occasion, Bi2O2CO3/Bi/Bi2WO6 ternary composites are obtained after one step method. High resolution transmission electron microscopy clearly reveals each component in composites. The as prepared samples could be applied in various photocatalytic activities. Under solar light irradiation, Bi2O2CO3/Bi/Bi2WO6 composites exhibited prominent photodegradation performances for both ciprofloxacin and bisphenol A. Meanwhile, these composites could also be used in efficient photoreduction of CO2. The efficient photocatalytic activity could be mainly ascribed to Z scheme electron transfer mechanism in ternary composites, which is determined by surface redox reactions, active species trapping experiment, electron spin resonance spectrum.
author_names: Yuanyuan Zhang

Lili Wang

Fengying Dong

Qiao Chen

HaiYan Jiang

Mei Xu

Jinsheng Shi
title: Non additional carbon source one step synthesis of Bi2O2CO3 based ternary composite for efficient Z scheme photocatalysis.
venue: Journal of colloid and interface science
year: 2019

abstract: Abstract The construction of solid state Z scheme heterojunction photocatalytic system to efficiently tailor the photoinduced charge separation is of great significance to water purification. In this study, we reported for the first time the controlled preparation of Bi2S3/SnS2/Bi2O3 double Z scheme heterojunction photocatalyst by a simple one pot solvothermal route. The experimental results with regard to rhodamine B (RhB) degradation showed that the as fabricated heterojunctions can significantly enhance photocatalytic activity in comparison with pure Bi2S3. In addition, the optimized BiS 4 sample possessed good simulated sunlight photocatalytic efficiency towards the degradation of other types of dyes, including methyl orange (MO) methylene blue (MB) orange IV (OG IV) and crystal violet (CV) By further probing the charge separation and migration behaviors, studying the band structure, as well as conducting the active species trapping experiments, a possible double Z scheme photocatalytic mechanism was proposed, which not only benefited the efficient photogenerated electron hole pair separation but also demonstrated advanced capacity for the removal of organic dyes. This work would pave the route towards the design of novel Z scheme photocatalytic systems for energy conversion and environmental remediation.
author_names: Chongfei Yu

Wang Ke

Pengyan Yang

Shengnan Yang

Chen Lu

Yingze Song

Shuying Dong

Jingyu Sun

Jianhui Sun
title: One pot facile synthesis of Bi 2 S 3 /SnS 2 /Bi 2 O 3 ternary heterojunction as advanced double Z scheme photocatalytic system for efficient dye removal under sunlight irradiation
year: 2017

abstract: Abstract The novel BiOBr/reduced graphene oxide/protonated g C3N4 (BiOBr/RGO/pg C3N4) composites were successfully synthesized by using a facile solvothermal synthesis method. The structure, morphology, optical and electronic properties were explored by X ray diffraction (XRD) X ray photoelectron spectroscopy (XPS) transmission electron microscopy (TEM) UV Vis diffuse reflectance spectroscopy (DRS) and photoelectrochemical measurement. The photocatalytic activities of as synthesized samples were evaluated by the degradation of Rhodamine B (Rh B) and tetracycline hydrochloride (TC) aqueous solution under visible light irradiation (l 420nm) Compared with BiOBr, protonated g C3N4 (pg C3N4) BiOBr/pg C3N4 and RGO/pg C3N4, BiOBr/RGO/pg C3N4 composites exhibited higher photocatalytic activity. The total organic carbon (TOC) removal ratios of Rh B and TC over 10% BiOBr/RGO/pg C3N4 were 88% and 59% respectively. The excellent photcatalytic performance was investigated by photoluminescence spectroscopy (PL) the radical quenching and electron spin resonance experiments. A Z scheme charge transfer mechanism was proposed, in which RGO acted as an electron transfer mediator. It was worth pointing out that the closely contacted two dimensional interface among the BiOBr, the RGO and pg C3N4 promoted the separation and transfer of photo generated charge carriers, and thus enhanced the photocatalytic efficiency.
author_names: Yongchao Bao

Kezheng Chen
title: Novel Z scheme BiOBr/reduced graphene oxide/protonated g C 3 N 4 photocatalyst: Synthesis, characterization, visible light photocatalytic activity and mechanism
year: 2018

abstract: This work presents a modified solvothermal process for a facile synthesis of high thermally stable nanocrystalline anatase TiO NPs doped with Cu O NPs. A Z scheme mechanism was used to account for the enhanced photocatalytic activity exhibited by these materials. Also, the nanocomposite was impregnated in cotton fabric to obtain a modified fiber with high thermal stability, self cleaning, enhanced UV protection, and antibacterial activity. The as prepared nanomaterials and the coated fabric were characterized by various physicochemical techniques such as XRD, EDXRF, TGA, TEM, HRTEM, and SEM. The Cu O/TiO molar ratio in the nanocomposite was found to possess a pronounced impact on the crystalline structure, size and morphology of TiO NPs. The XRD revealed proper substitutions of the few Ti sites by Cu ions in TiO host lattice. Optical measurements showed that the plasmonic peak of the Cu O/TiO nanocomposite was affected by the copper doping concentration, enhancing self cleaning of Cu O/TiO under direct sunlight. The TiO /fiber self cleaning efficiency (12 h for MB removal) was increased by the in situ growing of Cu O (5.5 h) Antibacterial activity studies revealed high potential activity of Cu O/TiO against both Gram positive (Staphylococcus aureus) and Gram negative (Escherichia coli, Kleissella pneumonia, Saccharomyces sp. bacteria. The promising photocatalytic and biocidal activity of our synthesized Cu O/TiO nanocomposites was ascribed to the reactive oxygen species generated by the Z scheme mechanism under direct Sunlight.
author_names: Mohamed M Ibrahim

Amine Mezni

Hamdy S El-Sheshtawy

Abeer A Abu Zaid

Mohammed Alsawat

Nagi El-Shafi

Sameh I Ahmed

Abdallah A Shaltout

Mohammed A Amin

Tushar Kumeria

Tariq A Altalhi
title: Direct Z scheme of Cu2O/TiO2 enhanced self cleaning, antibacterial activity, and UV protection of cotton fiber under sunlight
venue: Applied Surface Science
year: 2019

abstract: Abstract A novel one pot solvothermal route was employed to construct O and S co doped graphitic carbon nitride quantum dots (OSCNQDs) hybridized with Bi2MoO6 (BMO) photocatalyst and utilized to catalyse aqueous phenol from simulated wastewater under extended visible light exposure. The photodegradation analysis depicted that the (OSCNQDs/BMO) nanohybrid exhibited incremented photocatalysis of phenol (98 under visible light illumination which is due to the effective coupling and formation of Z scheme heterostructure which rendered superior space isolation and retained high redox abilities. The OSCNQDs might contribute to the extended absorption of visible light as well as increased adsorption of phenol on the surface of photocatalyst. As a result, the nanohybrid displayed prominent absorption in visible region, improved space charge isolation and superior photoactivity which can be utilized as an effective approach for the photo assisted degradation of organic pollutants.
author_names: Abhinandan Kumar

Pankaj Raizada

Pardeep Singh

Ahmad Hosseini-Bandegharaei

Vijay Kumar Thakur
title: Facile synthesis and extended visible light activity of oxygen and sulphur co doped carbon nitride quantum dots modified Bi2MoO6 for phenol degradation
year: 2020

abstract: A novel Bi2MoO6/reduced graphene oxide/BiOBr (Bi2MoO6/RGO/BiOBr) composite was successfully synthesized via a facile solvothermal synthesis and precipitation method. The Bi2MoO6/RGO/BiOBr composite was characterized by X ray diffraction, X ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, UV vis diffuse reflectance spectroscopy (UV vis DRS) and photoelectrochemical measurements. The photocatalytic properties were explored for removal of methylene blue (MB) and norfloxacin (NFX) under visible light irradiation. The Bi2MoO6/RGO/BiOBr composite exhibits the highest degradation rate compared with Bi2MoO6, BiOBr and Bi2MoO6/BiOBr composite, and that removal ratios of MB and NFX were 96.93% and 78.12% respectively. A Z scheme catalytic mechanism suitable for the system was proposed based on the results of UV vis DRS, free radical trapping experiments and M S carve analysis, in which RGO as an electronic medium can accelerate electron transfer. It is noteworthy that the close contact interface structure promotes the separation of electrons and holes and improves the photocatalytic performance.
author_names: Rui Zhang

Qiong Han

Yu Li

Tongqing Zhang

Yu-qiong Liu

Kunlin Zeng

Chen Zhao
title: Fabrication and characterization of high efficient Z scheme photocatalyst Bi2MoO6/reduced graphene oxide/BiOBr for the degradation of organic dye and antibiotic under visible light irradiation
venue: Journal of Materials Science
year: 2019