BiOCl Nanocomposite Research Articles

Aerogel-derived carbon quantum dots modified BiOCl nanocomposites with augmented oxygen vacancies for enhanced photodegradation of antibiotics

Composite carbon quantum dots (CQDs), characterize as zero-dimensional carbon nanomaterial, play a crucial role in accelerating the separation of photoelectron-hole pairs within photocatalysts. Moreover, they introduce abundant oxygen vacancies (OVs) and facilitate the formation of new defect levels. Therefore, in this study, CA/BiOCl-x was synthesized via the hydrothermal method using carbon aerogel (CA) as the precursor for CQDs endowed with visible light activity. Through the degradation of tetracycline hydrochloride (TCH), the results demonstrate that CA/BiOCl-6 % exhibits the most prominent photocatalytic efficiency, showcasing a degradation rate of TCH under visible light irradiation fourfold higher than that of pristine BiOCl. Furthermore, the degradation activity is significantly enhanced under full spectrum irradiation, achieving a degradation rate of ∼100 %. The observation indicated efficient integration of CQDs into BiOCl through C = O, introducing abundant OVs. Electrochemical analysis revealed that the enhancement of catalyst recombination significantly augmented both the lifetime of photogenerated carriers and the intensity of photocurrent. Active species quenching experiments indicated the superior role of superoxide radical (•O2−) in CA/BiOCl mediated TCH degradation. Liquid chromatography-mass spectrometry further confirmed the degradation pathways of contaminants. This study provides novel insights into the development of efficient photocatalysts for remediations of organic pollutants.

Facile fabrication of novel In2S3–BiOCl nanocomposite-supported porous polymer monolith as new generation visible-light-responsive photocatalyst for decontaminating persistent toxic pollutants

We report synthesizing a novel p-In2S3 and n-BiOCl heterojunction nanocomposite of varying β-In2S3 stoichiometry (10–50%) fabricated via. The hydrothermal and combustion methods. In2S3–BiOCl nanocomposites were homogeneously integrated onto a porous poly(ethylene glycol dimethacrylate) monolith to serve as a high-performance visible-light-responsive renewable photocatalyst decontaminating toxic organic pollutants such as Rhodamine B. The photocatalyst's structural and surface features were characterized using ppowder X-ray diffraction, X-ray photoelectron spectrometer, high-resolution transmission electron microscopy–selected area electron diffraction, field-emission scanning electron microscopy-energy-dispersive X-ray spectral, UV–Vis-diffuse reflectance spectral, photoluminescence spectral, Fourier transforms infrared, electrochemical impedance spectroscopy, and Brunauer–Emmett–Teller/Barrett-Joyner-Halenda (BJH) analysis. Using 20 wt% of In2S3 composition in the In2S3–BiOCl nanocomposite facilitated better electron–hole pair separation with excellent visible light responsive photocatalytic activity, confirmed through electrochemical impedance spectroscopy, photoluminescence spectral and bandgap measurements. The Brunauer–Emmett–Teller/BJH analysis revealed that the In2S3–BiOCl nanocomposite-loaded poly(ethylene glycol dimethacrylate) monolith had high surface area and pore dimensions, with voluminous photoactive sites. The role of analytical parameters such as pH, nanocomposite ratio, photocatalyst dosage, dye concentration, photosensitizers/oxidizers, and light intensity were studied/optimized. Under the optimized conditions of pH 2.0, 100 mg photocatalyst dosage, 30 ppm dye concentration, 1.0 mM KBrO3, and 300 W/cm2 visible light intensity, the monolithic photocatalyst showed a dissipation efficiency of ≥98.6% for Rhodamine B in ≤0.3 h. The renewable photocatalyst can be reused for six cycles without loss in efficiency/performance and proved promising in efficiently decontaminating persistent organic pollutants at an affordable cost and time.

ZIF-67/BiOCl nanocomposites for highly efficient detection of NO2gas at room temperature

Metal–organic frameworks (MOFs) are considered ideal gas-sensing materials owing to their unparalleled tunability, large surface area, rich porosity, and extensive active metal sites.

Facial synthesis of mesoporous {Mo132}/BiOCl for the efficient oxidative desulfurization of fuel

The Keplerate nanoball iso-polyoxomolybdate {Mo132} supported on BiOCl was prepared and assessed as a green, innovative, and low-cost oxidative desulfurization catalyst for dibenzothiophene-containing model oil (DBT). The XRD, FT-IR, Raman, SEM, TEM, BET, and XPS characterize the prepared catalysts. The optimum operating parameters were identified by evaluating factors such as reaction time, catalyst quantity, oxygen to sulfur molar ratio, and temperature. Experiments indicated that the catalyst was greatly efficient in removing DBT, with a sulfur removal rate up to 100 % at optimum conditions (catalyst dosage = 5 g/L, O/S = 10, time = 180 min, and temperature = 40 °C) utilizing hydrogen peroxide (H2O2) as oxidizing agent and acetonitrile as extracting solvent. Furthermore, {Mo132}/BiOCl showed high stability and catalytic activity like that of the fresh one after four cycles. ODS activity of the catalyst was evaluated for various thiophenes (thiophene, BT, 4,6-DMDBT, and DBT) derivative and feed at optimum conditions. The proposed mechanism for catalytic oxidation of DBT in the existence of {Mo132}/BiOCl nanocomposite was studied.

G-C3N4/oxygen-deficient BiOCl nanocomposite assisted by distinguished properties of graphene quantum dots for the efficient photocatalytic removal of organic vapors

In this study, photocatalytic properties of a graphene carbon nitride (g-C3N4) oxygen-deficient BiOCl (ODBOC) nanocomposite, which was assisted by the distinguished properties of graphene quantum dots (GQDs/gCN/ODBOC), in the decomposition of harmful organic vapors were investigated. The GQDs/gCN/ODBOC ternary composite was prepared using a facile chemical-mixing method. The presence of oxygen vacancies in ODBOC and the GQDs/gCN/ODBOC nanocomposite was confirmed by electron spin resonance and X-ray photoelectron spectroscopy. Compared to pristine BiOCl, ODBOC exhibited a higher performance, while compared with those of the selected photocatalyst counterparts, GQDs/gCN/ODBOC exhibited a higher performance; particularly, the removal efficiency of hexanal over this catalyst increased up to 95%. The superior performance of the above photocatalyst was related to two distinguished properties of GQDs: improved visible-light absorption by their upconverted photoluminescence and promoted charge-separation ability by their electron attraction properties, as well as the Z-scheme charge transfer at the junctions between g-C3N4 and ODBOC. In addition, the GQDs/gCN/ODBOC fabricated using a GQD solution of 5 mL revealed the highest performance and satisfactory photochemical stability during recycling tests. Finally, the photocatalytic mechanism for the pollutant degradation over GQDs/gCN/ODBOC was proposed on the basis of band-energy structures and hydroxyl radical measurements.

Synthesis and characterization of a novel Fe3O4@SiO2–BenzIm-Fc[Cl]/BiOCl nano-composite and its efficient catalytic activity in the ultrasound-assisted synthesis of diverse chromene analogs

A new magnetic nano-catalyst bearing ionic liquid, ferrocene and BiOCl was synthesized and its catalytic activities were evaluated in the synthesis of a wide variety of 2-amino-3-cyano-4H-chromene derivatives (54 compounds) under ultrasound irradiation.

Synthesis of novel p-n heterojunction m-Bi2O4/BiOCl nanocomposite with excellent photocatalytic activity through ion-etching method

A novel p-n heterostructure photocatalyst m-Bi2O4/BiOCl was successfully synthetized through a facile ion-etching method. Via adjusting the added volume of HCl solution, a series of different ratios of composite photocatalysts were obtained. The as-prepared samples of physical, chemical and optical characteristics were examined by X-ray diffraction, scanning electron microscope, transmission electron microscope, energy dispersive X-ray spectroscopy, selected-area electron diffraction, Fourier transform infrared absorption, Raman microscope, N2 adsorption-desorption, X-ray photoelectron spectroscopy and UV-vis spectrum technologies. The photocatalysts showed high degradation rate and complete mineralization ability for methyl orange and tetracycline solution under visible light. The reaction rate constant of m-Bi2O4/BiOCl for methyl orange was 52.28 times higher than that of BiOCl. The characterization presented a good stability of materials. Furthermore, the photocurrent response test certified that the heterostructure effectively accelerated the separation and migration of photo-generated carries. The scavenger experiments evidenced that hole (h+) and superoxide radical (•O2—) were the primary active radicals. A possible photocatalytic mechanism was proposed. This work provided an alternative photocatalyst applied to water environmental remediation.

Novel rattle-type magnetic Fe3O4@Ag@H-BiOCl photocatalyst with enhanced visible light-driven photocatalytic activity

A novel rattle-type magnetic Fe3O4@Ag@H-BiOCl nanocomposite was prepared successfully by a facile solvothermal method. The structures, morphologies, magnetic and electronic properties and photocatalytic performance of as-prepared products were successfully characterized by multiple techniques. The results show that the composites exhibit an obvious cavity, excellent magnetic properties, largely increased electron–hole separation efficiency and visible-light absorption. Due to the existence of an inner cavity, this novel photocatalyst exhibits excellent adsorption and transfer performance to organic pollutants in aqueous systems. The photocatalytic activity of the materials was evaluated by the photocatalytic degradation of rhodamine B (RhB) and antibiotic agent ciprofloxacin (CIP). It was found that the Fe3O4@Ag@H-BiOCl exhibited much better photocatalytic performance than pure BiOCl, which displayed the degradation rates of RhB and CIP were 99.5 and 98.3% after 120 min under visible light irradiation, respectively. The enhanced photocatalytic activities may result from the synergetic promoting effect of surface plasmon resonance of Ag and facet-dependent oxygen vacancy of BiOCl, which significantly improves visible-light absorption capacity and separation rate of charge carriers. A possible mechanism of the enhancement of visible photocatalytic activity was proposed. This study provides a promising approach to improve visible-light-response and recycle photocatalysts to treat waste water.

Hybrid density functional study on the mechanism for the enhanced photocatalytic properties of the ultrathin hybrid layered nanocomposite g-C3N4/BiOCl

To investigate the origin of the high photocatalytic performance of experimentally synthesized g-C3N4/ BiOCl, we studied its geometry structure, electronic structure, and photocatalytic properties by means of hybrid density-functional theory (DFT). The calculated band alignment of g-C3N4 and few-layer BiOCl sheets clearly shows that g-C3N4/ BiOCl is a standard type-II nanocomposite. The density of states, Bader charge, partial charge density, charge density difference, and the effective masses show that electron-hole pair can be effectively separated in the g-C3N4/BiOCl interface. The calculated absorption coefficients indicate an obvious redshift of the absorption edge. The band gap of g-C3N4/BiOCl can be modulated by external electric field, and a semiconductor-semimetal transition is observed. The type-II vdW heterostructure is still maintained during the changes of external electric field. Especially, when the electric field reaches to +0.7 V/Å, the impurity states have been eliminated with the band gap of 2.3 eV. An analysis of optical properties shows that the absorption coefficient in the visible-light region is enhanced considerably as the electric-field strength increases. Our calculation results suggest that the ultrathin hybrid layered g-C3N4/BiOCl nanocomposite may have significant advantages for visible-light photocatalysis.

Synthesis of Different Shapes ZnFe₂O₄–BiOCl Nanocomposites for Photocatalytic Reduction of CO₂ in Cyclohexanol.

Nanosheet and hierarchical microsphere nanostructures of ZnFe₂O₄–BiOCl nanocomposites with various ZnFe₂O₄ contents were prepared through hydrothermal deposition method. The morphology and structure of the as-prepared samples were systematically characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV-vis diffuse reflectance spectroscopy, Brunauer-Emmert-Teller method, and photoluminescence spectra. The photocatalytic activities of the two different shapes of ZnFe₂O₄–BiOCl composites have been evaluated by photocatalytic reduction of CO₂ in cyclohexanol under UV light irradiation. The results showed that cyclohexanol was oxidized to cyclohexanone (CH), and CO₂ was reduced and then reacted with cyclohexanol to produce cyclohexyl formate (CF). The ZnFe₂O₄–BiOCl composites with different shapes showed much higher CF and CH yields than those of pristine BiOCl and mechanically mixed samples, respectively. When the ZnFe₂O₄ content in the composites reached 9%, two different shapes of ZnFe₂O–BiOCl composites both achieved the highest photocatalytic activities. In contrast, the activities for photocatalytic reduction of CO₂ in cyclohexanol over hierarchical microsphere ZnFe₂O₄–BiOCl composites were higher than those of nanosheet structure samples. The higher activities over hierarchical microsphere composites could be attributed to its unique hierarchical structure, large illumination area, and low Photoluminescence (PL) emission intensity, which were beneficial for the separation of photogenerated charge carriers. This work provided a novel approach for the design and construction of highly efficient photocatalyst and reaction system for photoreduction of CO₂.

In situ preparation of g-C3N4/bismuth-based oxide nanocomposites with enhanced photocatalytic activity

Different mass percents of g-C3N4/Bi2O2CO3 and g-C3N4/BiOCl nanocomposites with intimately contacted interfaces were synthesized in situ by mixing Bi2O3 nanoparticles with melamine or guanidine hydrochloride and calcinating at 550°C for 3h. The fabricated nanocomposites were well-characterized by various analytical techniques. The results showed that the Bi2O2CO3 and BiOCl nanosheets grow out from the g-C3N4 bulk, producing closely contacted interfaces between the Bi oxide component and the g-C3N4 component. The UV–vis diffuse reflectance spectra of g-C3N4/Bi2O2CO3 and g-C3N4/BiOCl nanocomposites exhibited increased visible light absorption compared to g-C3N4 and Bi2O3 separately. Moreover, the nanocomposites showed significantly enhanced photocatalytic activity for the degradation of dibutyl phthalate and methyl orange under visible light. A proposed photocatalytic mechanism for the enhanced photoactivity of nanocomposites was investigated by scavenging experiments and fluorescent spectroscopy. The increased photocatalytic activity is mainly attributed to the effective separation and transfer of photo-induced carriers in the intimate contact between g-C3N4 and Bi2O2CO3 or BiOCl. The results showed that the different precursors of g-C3N4 have a significant effect on the composite's structure; i.e., Bi2O3 can react to form different bismuth-based oxides depending on the different precursors used to generate g-C3N4. This work demonstrates a convenient way to fabricate visible light responsive materials with potential for environmental remediation.

In situ synthesis of N-doped carbon nanotubes–BiOCl nanocomposites and their synergistic photocatalytic performance

N-Doped carbon nanotube–BiOCl (NCB) nanocomposites were prepared by anin situgrowth strategy. The NCB nanocomposites possessed enhanced photocatalytic efficiency, compared with CNxNTs, BiOCl 3D flower-like hierarchitectures, and P25.

Preparation and Photocatalytic Activity of Sepiolite/Flower-Like BiOCl Nanocomposites

Sepiolite/flower- like BiOCl nanocomposites as photocatalyst have been successfully prepared by hydrolysis precipitation method. And the influence of temperature, pH and Bi(NO3)3concentration on the unique morphology of the nanocomposites was investigated. Moreover, the photocatalytic activity of these nanocomposites was examined for the degradation of rhodamine B. The results show that the flower-like BiOCl is uniformly dispersed on the sepiolite and this nanocomposites exhibit a photocatalytic efficiency of 14.29%-16.67% higher than that of pure BiOCl nanosheets for the degradation of rhodamine B, and the catalyst has an excellent cycling stability.

Ag–BiOCl nanocomposites prepared by the oxygen vacancy induced photodeposition method with improved visible light photocatalytic activity

Ag–BiOCl nanocomposites were prepared through a visible light induced photodeposition method by taking the advantage of oxygen vacancy in {001} facets of BiOCl. The prepared Ag–BiOCl (Vis–Ag–BiOCl) could efficiently degrade methyl orange (MO) and oxidize NO under visible light irradiation. Moreover, it exhibited an enhanced visible light driven photocatalytic activity compared to Ag–BiOCl (UV–Ag–BiOCl) nanocomposites prepared by the traditional UV light photodeposition method, even that the latter showed a much stronger visible light absorption ability. Photocurrent and electrochemical impedance spectroscopy (EIS) tests indicated that the more efficient photoinduced charge separation and transfer in Vis–Ag–BiOCl could be attributed to the improvement of the visible light photocatalytic activity.

Microwave-assisted synthesis of flower-like Ag–BiOCl nanocomposite with enhanced visible-light photocatalytic activity

Flower-like BiOCl and Ag–BiOCl nanocomposite have been successfully fabricated via a microwave irradiation process. The structure and morphology of the samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM). The photocatalytic property of the BiOCl and Ag–BiOCl nanocomposite was evaluated by photodegradation of Rhodamine B (RhB) under visible light illumination. Results of photodegradation tests reveal that the Ag–BiOCl nanocomposite has much better photocatalytic activity than pure BiOCl. The excellent photocatalytic activity can be ascribed to the high effective electron–hole separation which results in the significant improvement of the photocatalytic activity of BiOCl.

Synthesis, spectral, thermal, structural and micro-structural features of new nano-(Zn, Al and Bi) compounds

The [Zn 5(OH) 8Cl 2·H 2O], [NH 4Al 3(SO 4) 2(OH) 6] and BiOCl nano-composites were synthesized by a new reactions of acetamide with ZnCl 2, BiCl 3 and Al 2(SO 4) 3 salts, respectively, in an aqueous media at ∼90–95 °C. The infrared spectra, Raman laser, scanning electron microscopy, X-ray powder diffraction, thermogravimetric analysis (TGA/DTG), as well as microanalysis, CHN, of the solid products were discussed. The results are referred to the absence of the bands of acetamide and appearing the characteristic bands of (OH, H 2O and M–O), (OH, NH 4, SO 4 and M–O) and (Bi–O) for Zn(II), Al(III) and Bi(III) compounds, respectively. A general mechanism describing the formation of nano-composites materials and decomposition of acetamide were suggested. Finally, the thermodynamic parameters of the decomposition behaviors of the nano-composites were revealed by the non-isothermal Coats–Redfern and Horowitz–Metzger methods.