Adsorption Photocatalytic Degradation Research Articles

Preparation of Cu/Cu2O/BC and Its Performance in Adsorption-Photocatalytic Degradation of Methyl Orange in Water.

In this study, we prepared a low-cost novel Cu/Cu2O/BC nanocomposite visible-light photocatalyst by the impregnation method using CuSO4·5H2O and rice husk biochar (BC) as raw materials and Na2S2O4 as a single reductant to improve the stability and dispersion of the Cu/Cu2O nanoparticles, in order to solve their aggregation tendency during photocatalysis. The morphology and structure of the Cu/Cu2O/BC were characterized using various analytical and spectroscopic techniques. The photocatalytic effect and cyclic stability of the synthesized photocatalyst on methyl orange (MO) removal were investigated under visible light radiation and various parameter conditions, including the mass ratio of BC to Cu/Cu2O, initial MO concentration, pH, temperature, and catalyst dosage. The results show that the synthesized Cu/Cu2O/BC nanocomposite composed of Cu/Cu2O spherical particles was loaded on the BC carrier, which has better stability and dispersion. The best adsorption-photocatalytic effect of the Cu/Cu2O/BC is exhibited when the mass ratio of BC to Cu/Cu2O is 0.2. A total of 100 mg of Cu/Cu2O/BC can remove 95% of the MO and 88.26% of the COD in the aqueous solution at pH = 6, T = 25 °C, and an initial MO concentration of 100 mg/L. After five cycles of degradation, the MO degradation rate in the sample can still remain at 78.41%. Both the quasi-secondary kinetic model and the Langmuir isothermal adsorption model describe the adsorption process. Additionally, the thermodynamic analysis demonstrates that the photocatalytic process follows the quasi-primary kinetic model and that the removal process is of spontaneous heat absorption. The photocatalyst described in this paper offers a cost-effective, easily prepared, and visible-light-responsive solution for water pollution treatment.

Synergistic adsorption-photocatalytic degradation of tetracycline by S-scheme InVO4/ZnIn2S4 heterojunction: mechanism, toxicity assessment, and potential applications

The development of materials with dual adsorption/photocatalytic functions for the removal of difficult-to-degrade organics is a very promising and challenging strategy. In this paper, a novel S-scheme heterojunction photocatalyst, InVO4/ZnIn2S4, was successfully synthesized with a unique hierarchical structure, which provides plenty of accessible adsorption/photocatalytic sites with a high light-harvesting rate (by multiple reflections). The experimental results show that optimized InVO4/ZnIn2S4 (5-IV/ZIS) has superior removal performance, whose adsorption-photocatalytic synergistic removal of tetracycline (TET) can reach 69.31 % after 15 min and 90.69 % after 45 min. Based on the analysis of the mechanism, the excellent removal performance can be attributed to the adsorption of the target onto the material by hydrogen bonding, followed by the degradation of the adsorbed target by active substances (h+ > O2•− > e- >1O2 >•OH) generated by the S-scheme heterojunction. In addition, the possible pathways for the photocatalytic removal of TET on 5-IV/ZIS were investigated by HPLC-MS analysis. T.E.S.T. and E. coli inhibition experiments demonstrated a significant reduction in the toxicity of TET after the photocatalytic reaction. In conclusion, the novel multifunctional photocatalyst 5-IV/ZIS prepared in this study can be used for the efficient treatment of organic compounds in wastewater with a bright application prospect.

Synthesis of polyaniline-doped magnetic iron foam photo catalyst (PANI@mIF) for integrated adsorptive photocatalytic degradation of nicosulfuron

ABSTRACT Nicosulfuron have low volatility and slow biodegradation rate, leading to its long persistency in soil and crops, which further upraised the risk of contamination of nearby water and severe damage to the crop rotation as may be its precursors are more harmful than nicosulfuron itself. In the present work, we performed a degradation study for the efficient removal of nicosulfuron from soil and water using Polyaniline-doped magnetic iron foam (PANI@mIF). The Photo catalyst was synthesised by doping of polyaniline on magnetic iron foam at 70°C and applied for the efficient photocatalytic degradation of nicosulfuron. PANI@mIF was then characterised through FTIR, SEM, EDX and XRD. The degradation of nicosulfuron was investigated under UV radiations and the resulted data were examined by fitting isotherms models. The Langmair model is well fitted to the adsorption data with R2 of 0.925, which demonstrates monolayer adsorption of nicosulfuron on the surface of PANI@mIF. The maximum adsorption capacity and percent degradation of 87% was achieved with PANI@mIF. Comparatively, good adsorption capacity of PANI@mIF is attributed to a large number of H bonding and electrostatic interactions. Kinetic study indicates the adsorption of nicosulfuron by PANI@mIF followed 2nd order kinetics with R2 of 0.958.The negative values of Gibbs free energy (−18294.3, 19543.1,-7530.4, −7307.7 and −7969.8), enthalpy (−1.97 × 10−4) and entropy (−3.54 × 10−3) indicate spontaneous and exothermic nature of the process. The reusable nature of PANI@mIF with 5 batches reflected its inventive photo catalytic behaviour for real sample applications and waste water treatment.

Fabrication of porous biochar supported Bi2MoO6 photocatalyst for efficient degradation of ciprofloxacin in seawater under visible light irradiation: Mechanistic investigation and intermediates analysis

Efficient separation of photocarriers is a critical approach for advancing high-performance photocatalyst systems to effectively remove environmental contaminants. In this investigation, a hydrothermal technique was employed to synthesize composites of Bi2MoO6 and porous biochar derived from banana peels (BPB). The samples underwent various characterization methods to assess their composition, morphology, and photoelectrochemical properties. The BPB/Bi2MoO6 composite exhibited a synergistic adsorption and photocatalytic impact in eliminating the antibiotic ciprofloxacin (CIP) from pure water and seawater. The optimized BPB/Bi2MoO6 sample displayed a significant degradation efficiency of 98.7 % for CIP after 90 min of visible-light exposure in pure water. In artificial seawater, the degradation efficiency for CIP remained high at 93.6 %, which was 12.2 times greater than that of pure Bi2MoO6. The study also explored the impact of various factors such as catalyst dosage, solution pH, and pollutant concentration on the photocatalytic performance of BPB/Bi2MoO6. Moreover, the catalyst exhibited enhanced efficiency in the adsorption-photocatalytic degradation of CIP within a continuous flow reaction system. The enhanced photocatalytic performance was attributed to the composite's exceptional adsorption capacity, enhanced response to visible light, and efficient separation of photoinduced electron-hole pairs. Furthermore, the BPB/Bi2MoO6 photocatalyst displayed good stability and recyclability over five consecutive photodegradation cycles. Radical trapping and electron spin resonance (ESR) experiments verified that the degradation of CIP was mainly driven by •OH and h+ radicals. A thorough investigation employing density functional theory (DFT), radical trapping and ESR tests, and liquid chromatography mass spectrometry (LC-MS) was conducted to elucidate the degradation mechanism and pathways. Furthermore, toxicity assessment software was utilized to illustrate the progressive reduction in toxicity of the intermediate products. In conclusion, this study provides valuable insights into the role of biochar in enhancing the photocatalytic degradation of pollutants and offers guidance for the future development of environmentally friendly photocatalysts.

TiO2–Cu7S4 modified with a carbazole-based conjugated porous polymer for adsorption and photocatalytic degradation of bisphenol A

Adsorption-photocatalytic degradation of organic pollutants in water is an advantageous method for environmental purification. Herein, a feasible strategy is developed to construct a novel dual S-scheme heterojunctions Cu7S4–TiO2-conjugated polymer with a donor–acceptor structure. There are abundant adsorption active sites for adsorption in the porous structure of the composites, which can rapidly capture pollutants through hydrogen bonding and π-π interactions. In addition, the dual S-scheme heterojunctions effectively improve carrier separation while maintaining a strong redox ability. Thus, the optimized 1.5% CST-130 catalysts can adsorb 71% of 20 ppm BPA in 15 min and completely remove it within 30 min with high adsorption capacity and photodegradation efficiency. Therefore, this study provides a new inspiration for synergistic adsorption and degradation of BPA and the construction of dual S-scheme heterojunction.

Ternary heterojunction of cross-linked benzene Polymer/Bi2MoO6-Graphene oxide catalysts promote efficient adsorption and photocatalytic removal of oxytetracycline

Antibiotics are refractory degradable organic pollutants that present a significant hazard to water environments. In this work, a ternary composite (KB/BMO-GO) comprising of graphene oxide (GO), Bi2MoO6 (BMO), and a cross-linked benzene polymer (KB) was synthesized and applied to promote the synergistic adsorption-photocatalytic degradation of the refractory pollutant, oxytetracycline (OTC). The inclusion of GO and KB in the composite enhanced the OTC adsorption performance of the catalysts, and the construction of Z-scheme heterojunction promoted the photogenerated charge separation efficiency and broadened the range of light absorption, thereby enhancing the photocatalytic performance. Moreover, we compared the performance of catalysts loaded with different mass ratios of KB (x% KB/BMO-GO). Among them, the 15 % KB/BMO-GO catalyst sample had the best OTC degradation performance. Specifically, 15 % KB/BMO-GO could adsorb 69.7 % of OTC in 30 min, reaching an OTC degradation rate of 93.3 % under visible light irradiation. h+ and 1O2 are the main active substances in the photocatalytic process. In addition, the catalysts are acid-alkali and salt-resistant, as well as good reusability. This study provides a valuable reference for the preparation of highly efficient photocatalysts for synergistic adsorption-photodegradation processes.

Manganese dioxide-coated biocarbon for integrated adsorption-photocatalytic degradation of formaldehyde in indoor conditions

Formaldehyde is a common indoor air pollutant with hazardous effects on human health. This study investigated the efficiency of biocarbon (BC) functionalized with variable contents of MnO2 for formaldehyde removal in ambient conditions via integrated adsorption-photocatalytic degradation technology. The sample with the highest formaldehyde removal potential was used to prepare a functional coating made of acrylic binder mixed with 20 wt% of the particles and applied on beech (Fagus sylvatica L) substrate. SEM images showed that MnO2 was deposited around and inside the pores of the BC. EDX spectra indicated the presence of Mn peaks and increased content of oxygen in the doped BC compared to pure BC, which indicated the successful formation of MnO2. Raman spectra revealed that the disorder in the BC's structure increased with increasing MnO2 loadings. FTIR spectra of BC–MnO2 samples displayed additional peaks compared to the BC spectrum, which were attributed to MnO vibrations. Moreover, the deposition of increased MnO2 loadings decreased the porosity of the BC due to pores blockage. The BC sample containing 8 % Mn exhibited the highest formaldehyde removal efficiency in 8 h, which was 91 %. A synergetic effect between BC and MnO2 was observed. The formaldehyde removal efficiency and capacity of the coating reached 43 % and 6.1 mg/m2, respectively, suggesting that the developed coating can be potentially used to improve air quality in the built environment.

Ni, Co-Embedded MOF-Derived N-Doped Bimetallic Porous Carbon for Adsorption-Photocatalytic Degradation of Organic Dyes and Antibiotics.

An efficient protocol for photocatalytic degradation of organic dyes and antibiotics has been successfully established via MOF-derived (MOF = metal-organic framework) Ni, Co-embedded N-doped bimetallic porous carbon nanocomposites (NiCo/NC). Such a NiCo/NC nanocomposite features well-distributed structures, suitable specific surface areas, and more active sites determined by various characterization analyses. The catalyst exhibits higher photocatalytic performance and stability toward the liquid-phase degradation of methylene blue (MB) under visible light irradiation for 60 min, after the adsorption-desorption equilibrium and the thorough degradation into H2O and CO2. Radical quenching experiments further confirmed the dominant effect of electron holes h+ and superoxide radical anions ·O2- for the MB photodegradation process. NiCo/NC was also appropriate for the degradation of Rhodamine B, methyl orange, tetracycline hydrochloride, and norfloxacin. Moreover, NiCo/NC is robust, and its photocatalytic activity is basically maintained after 8 cycles. This work is expected to provide additional information for the design of MOF-derived carbon material with more excellent properties and lay the foundation for further industrial applications.

Three-dimensional porous La(OH)3/g-C3N4 adsorption-photocatalytic synergistic removal of tetracycline.

La(OH)3/g-C3N4 composites were successfully synthesized via one-step calcination using urea, melamine, and La(NO3)3·nH2O as raw materials, and applied to UV-induced photocatalytic tetracycline (TC) removal. Comprehensive characterization by an X-ray diffraction (XRD), Fourier transform infrared reflection (FT-IR), high-resolution transmission electron microscope (HRTEM), and other techniques analyzed effects of La3+ doping, especially N vacancies and cyano groups as active sites. Compared to pure g-C3N4 and La(OH)3, synthesized La(OH)3/g-C3N4 composites exhibited a three-dimensional porous nanosheet structure with specific surface area of 83.62 m2/g and equilibrium TC adsorption capacity up to 285.59 mg/g; La(OH)3 doping significantly improved composite structure. After dispersing 10 mg La-CN-0.5 photocatalyst in 60 mL 40 mg/L TC solution, TC removal reached 91.08% in 30 min under UV irradiation, exhibiting excellent performance. Additionally, La-CN-0.5 showed significant adsorption-photocatalytic synergism, with the quasi-primary kinetic constant increased by 1.83-fold. The efficiency of high tetracycline (TC) concentration treatment through adsorption photocatalytic degradation by La-CN-0.5 was confirmed by the utilization of free radical trapping and electron spin resonance (ESR) tests. The significant involvement of ∙O2-, ∙OH, and h+ in this process was observed. These findings propose that the prepared La-CN-0.5 material exhibits a unique capability for adsorption photocatalysis, providing a promising approach for the efficient removal of high TC concentrations.

Insights into the photocatalytic degradation of hydrophobic organic contaminants on the surface of nitrogen doped silica: New findings of the formation of silicon-based substitution products

In this work, nitrogen-doped SiO2 (N-SiO2) was successfully synthesized to develop an “adsorption-photocatalytic degradation” water purification technology to remove hydrophobic organic contaminants (HOCs). As a representative of HOCs, decabromodiphenylethane (DBDPE) could be efficiently degraded under simulated sunlight after adsorption on the surface of N-SiO2. Due to the generation of reactive oxygen species (ROS) and silicon-based radicals, the photodegradation rate of DBDPE on water-SiO2 interface was 1.5-fold higher than that in water. Furthermore, the transformation pathways of DBDPE on N-SiO2 surface were compared with that in water. Bond breaking and debromination reactions were the common pathways, while hydroxylation and silicon-based substitution reactions were the specific transformation pathways for DBDPE on the surface of N-SiO2. Density functional theory (DFT) calculation was used to reveal the generation mechanism of silicon-based radicals and determine the rationality of the involvement of silicon-based radicals in DBDPE transformation. The energy barriers of silicon-based substitution reaction were comparable to that of hydroxylation and debromination reactions, which confirmed the plausibility of the generation of silicon-based substitution products. This study provides an efficient method for the disposal of HOCs, which also gives some new insights into the conversion mechanism of organic pollutants mediated by silicon-based radicals.

Research on the adsorption-photocatalytic synergistic degradation of tetracycline by Au nanoparticles/TiO2 nanorods/biochar

As a persistent antibiotic, tetracycline is widely used in medical and livestock farming fields. However, the long-term accumulation effect of tetracycline has a significant impact on the ecosystem. In this research, we integrated the processes of adsorption-photocatalytic degradation for organic pollutants by combining Sichuan Pepper shell biochar adsorption, TiO2 Nanorods photocatalytic oxidation, and Au nanoparticles Localized Surface Plasmon Resonance. The findings demonstrated that the specific surface area of Au nanoparticles/TiO2 nanorods/biochar has increased by 1287.6 m2/g compared to TiO2. Furthermore, when TiO2 is compounded with biochar, its particle size reduces by approximately half and forms C-Ti and N-Ti bonds. The composite catalyst exhibited the highest removal rate for tetracycline, nearly four times that of commercial TiO2 (P25), showing excellent application prospects. The enhanced composite structure improved its ability to capture sunlight, leading to more effective photocatalysis. This research explains the composite and synergistic mechanism of biochar, TiO2 nanorods, and Au nanoparticles, which could guide the removal of organic pollutants.

Structural design of core-shell ZIF-8@NH2-MIL-125 photocatalyst for synergistic adsorption-photocatalytic degradation of tetracycline hydrochloride

The development of a green, efficient, and reusable photocatalyst is of great importance for pollution remediation. Herein, a series of core-shell ZIF-8@NH2-MIL-125 composites (ZM-X) were prepared by epitaxial growth method. The in-situ homogeneous encapsulation of NH2-MIL-125 by ZIF-8 was achieved through the structural modulation, and the formed core-shell architecture exhibited outstanding synergistic effect of adsorption and photocatalysis for eliminating tetracycline hydrochloride (TCH), which dramatically enhanced the photocatalytic reaction rate. The results show that the TCH adsorption capacity of optimized ZIF-8@NH2-MIL-125 (ZM-2) is 70.25mgg–1, which can be fitted well the pseudo-second-order and Langmuir isotherm modes. Under 100min of visible light irradiation, the ZM-2 has the best synergistic removal rate on TCH (92.9%) compared with other samples, which is 6.5 times higher than of pristine NH2-MIL-125 (14.3%). The results of quenching experiments and ESR analysis clearly demonstrate that the superoxide radical (·O2–) dominates the TCH photodegradation reaction. In addition, ZM-2 can effectively remove TCH in different types of water systems (e.g., ultrapure water, tap water, lake water and actual pharmaceutical wastewater) through adsorption-photocatalytic synergy. Therefore, the novel core-shell material designed in this study has significant potential for environmental purification applications.

Ceria-decorated zeolite nanocomposite for synergistic adsorption and photocatalytic degradation of caffeine

The adsorption-photocatalytic degradation behaviour of emerging contaminant caffeine, an endocrine-disrupting compound was investigated. The adsorbent material zeolite with porous structure was modified by acid treatment to form a support for attachment of cerium oxide nanoparticles. The photoactive CeO2 was decorated on zeolite (Ceria/zeolite) using the surface modification approach. The physicochemical techniques used for the evaluation of a Ceria/zeolite nanocomposite were performed using XRD, FT-IR, SEM and EDS point mapping, and BET surface area analysis. The effect of caffeine removal was investigated by considering different parameters: pH (3–11), caffeine concentration (10–40 mg/L), and nanocomposite usage (250–750 mg/L). After 90 min of reaction, 68.32 ± 1.38 % adsorption/photocatalytic activity was achieved under dark conditions. UV irradiation increased photocatalysis-mediated removal by 90.63 ± 2.03 %. The process showed the best fit to the PFO model of adsorption kinetics with an R2 value of 0.98. The equilibrium data fitted well to the adsorption isotherm model of Langmuir isotherm, indicating monolayer adsorption. The residual toxicity evaluation revealed 75 % cell viability in the model algal strains. Furthermore, the synthesized nanocomposite photocatalyst can be reused for numerous cycles due to its high caffeine degradation and photocatalytic efficiency. Finally, utilizing HR-LCMS analysis, the probable mechanism of caffeine breakdown is elucidated.

Reduced graphene oxide-TiO2/sodium alginate/polyacrylamide composite hydrogel for enhanced adsorption-photocatalytic degradation of methylene blue

The discharge of dye wastewater from various industries has emerged as a critical environmental concern, necessitating the implementation of effective methods such as photocatalytic technology to mitigate organic dyes in water. Nevertheless, the poor photocatalytic activityability and low reusability of most semiconductor photocatalysts have hindered their large-scale practical application. In this paper, the reduced graphene oxide-titanium dioxide composite (rGO-TiO2) was prepared via a hydrothermal method and subsequently immobilized onto a three-dimensional structure composed of sodium alginate (SA) and polyacrylamide (PAM) through sunlight-induced polymerization and ionic cross-linking techniques, resulting in the fabrication of a novel photocatalytic composite hydrogel (rGO-TiO2/SA/PAM). The composite hydrogel was found to exhibit good photocatalytic degradation efficiency for methylene blue(MB), achieving complete removal of MB under UV light irradiation for 100 min at pH 7 when using a rGO:TiO2 ratio of 3 wt%. Additionally, the synthesis of rGO-TiO2/SA/PAM effectively harnesses solar resources through simple synthetic steps, enabling easy recovery and separation from dye wastewater (with a recovery rate of approximately after first use). In contrast, nano-TiO2 and rGO-TiO2 exhibit lower recovery rates (∼80%). Furthermore the material demonstrates enhanced selective adsorption-photocatalytic degradation of MB in acid-base dye mixtures under UV light irradiation.

Radiation construction and excellent performances of Ag NPs/TiO2/PEG/PVP multifunctional aerogel: Adsorption-photocatalytic degradation, photosensitive antibacterial and cytotoxicity

A cutting-edge method known as photocatalytic antibacterial technology can effectively eliminate drug-resistant bacterial strains and boast a wide-ranging antimicrobial capability. In the study, a novel Ag NPs/TiO2/PEG/PVP (ATPP) aerogel photocatalyst was synthesized by an electron beam in-situ radiation method using polyethylene glycol (PEG), polyvinylpyrrolidone (PVP), AgNO3, and TiO2 as raw materials. ATPP was characterized by X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS) and solid ultraviolet diffuse reflectance spectroscopy (UV–Vis DRS). The results demonstrated that silver ions were reduced to silver nanoparticles by electron beam radiation method. At the same time, the doping of silver nanoparticles (Ag NPs) enhanced visible-light adsorption. The degradation rate of methylene blue (MB) on 5% (in mass) ATPP could reach 81% under visible light for 180 min. Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were used as model bacteria to explore the antimicrobial properties of ATPP by zone of the inhibition method, plate counting method and live/dead bacterial staining. Cyclic antibacterial experiments showed that the antibacterial effect of ATPP was sustainable. Meanwhile, MTT assay and Hoechst33342/PI double staining were used to prove that the composite had good biocompatibility. The aerogel photocatalytic material has the potential to decrease microbial presence in both medical and environmental settings, making it a valuable tool for such applications.

Understanding the synergistic adsorption-photocatalytic degradation of EE2 using ZnO/Bi2MoO6{0 1 0}

Endocrine disrupting chemicals (EDCs) have adverse effects on the aquatic environment and human health as well. In this study, a ZnO/Bi2MoO6 {0 1 0} composite photocatalyst was fabricated via a simple hydrothermal calcination method for the efficient and synergistic adsorption-photocatalytic degradation of an environmental endocrine disruptor, 17α-ethynylestradiol (EE2). Adjusting the pH of the synthetic procedure, selectively exposed the highly reactive {0 1 0} crystalline surface of Bi2MoO6, and the surface hydrophilicity of the material decreased, enhancing the adsorption efficiency (74.74%) of the hydrophobic EE2 molecule. Density functional theory calculations showed that the chemisorption of the EE2 molecules takes place on the Bi2MoO6{0 1 0} surface owing to the binding of hydroxyl groups. Furthermore, by incorporating energy-band-matched ZnO to form heterojunctions with Bi2MoO6{0 1 0}, the obtained composites achieved a removal rate of 90% for EE2 after 40 min of visible light catalysis. Capture experiments and electron paramagnetic resonance spectra revealed that h+ and •O2- were the main active species, and the catalytic mechanism followed was that of a type II reaction. This study introduced a new strategy for the modification of photocatalysts resulting in a stable change in their surface properties for enhanced pollutant removal efficiency.

Adsorption-photocatalytic degradation abilities of γ-irradiated chitosan-ZnO-AgNP composite for organic dye removal and antibacterial activity.

We synthesized a γ-irradiated chitosan-ZnO-AgNPs (ICZA) composite by using a simple hydrogels method. We evaluated its adsorption/photocatalytic degradation abilities for the removal of an organic dye and its antibacterial activity. The XRD, SEM, TEM, EDS, and FTIR techniques were used to characterize the obtained samples. Based on the adsorption and degradation of methylene blue (MB) in the dark and under UV light irradiation, the adsorption and the photocatalytic activity of the as-obtained samples were evaluated. The optimum conditions for synthesizing the composite were as follows: contact time of 210 min, a dosage of 2 g/L, MB concentration of 40 mg/L, and a solution pH of 8.0. The ICZA had a high adsorption capacity, which was suitable for removing MB from the aqueous solutions; it showed a maximum adsorption capacity (qm) of 92.59 mg/g. The fit of the adsorption isotherms with the Langmuir model was satisfactory. The photocatalytic degradation ability of the composite was also better than that of other catalysts in the presence of UV light, with an apparent rate constant (kapp) of 3.08 × 10-2. The synthesized ICZA also showed good antibacterial activity against Staphylococcus aureus, with a minimum inhibitory concentration (MIC) and a minimum bactericidal concentration (MBC) of 12.5g/mL and 50g/mL under light-incubation and dark-incubation conditions. Finally, we discussed the hypothesized mechanism of the adsorption/photocatalytic activity and antibacterial activity of the ICZA composite in this study.

NaBiS2 decorated polysaccharide sponges for adsorption–photocatalytic degradation of dye under visible light illumination

Dye is emissions aggravating aquatic ecosystem pollution, and photocatalysis is considered the most appealing option to remove dyes by degradation. However, the current photocatalysts suffer from agglomeration, large bandgaps, high mass transfer resistance, and high operation cost. Herein, we present a facile hydrothermally induced phase separation and in situ synthesis strategy for fabrication of sodium bismuth sulfide (NaBiS2)-decorated chitosan/cellulose sponges (NaBiCCSs). The NaBiCCSs demonstrate unique polysaccharide cellular structure (150–500 μm), uniformly immobilized NaBiS2 nanoparticles (70–90 nm), narrow bandgap (1.18 eV), high photocurrent (0.74 μA/cm2), and outstanding compressibility. Benefiting from the characteristics and the high affinity to dyes, the NaBiCCSs provide innovative synergistic adsorption–photocatalytic degradation model for dye removal, attaining a superior methylene blue removal rate of 98.38 % under visible light illumination and offering good reusability. This study offers a sustainable technical solution for dye contaminant removal.

Silver oxide-zeolite for removal of an emerging contaminant by simultaneous adsorption-photocatalytic degradation under simulated sunlight irradiation

The existence of contaminants of emerging concern such as pharmaceuticals in the water sources become a growing concern matter because of their increased consumption, incomplete disposal, and potential impacts on living organisms. Accordingly, the removal of these bioactive compounds from the aqueous environment also becomes a vital issue and different treatment techniques have been investigated. The novelty of this work lies in the synthesis and implementation of silver oxide anchored on Y zeolite (Ag2O@Y Zeo) as an untried effective photocatalyst for the removal of emerging contaminants. Ranitidine (RANI) removal from aqueous solutions was investigated in this study by simultaneous adsorption-photodegradation induced via simulated sunlight irradiation in the presence of Ag2O@Y Zeo. Ag2O@Y Zeo was prepared by thermal treatment at 400 °C of Ag-form Y zeolite which was prepared by ion-exchange. The produced catalyst was characterized by X-ray diffraction, scanning electron microscopy, energy dispersive analysis by X-ray, Fourier transform infrared spectroscopy, nitrogen adsorption–desorption isotherms, UV–Vis diffuse reflection spectroscopy and photoluminescence spectroscopy. The simultaneous adsorption-photodegradation of RANI using Ag2O@Y Zeo was investigated at various conditions including a catalyst dose (5, 10, 30, 50, and 70 mg/ 100 mL), an initial RANI concentration (10, 20, 30, 40, and 50 mg/L), and a solution pH (3, 5, 9, and 11). According to the results, the RANI removal percentage was 97.51% obtained at Ag2O@Y Zeo dosage of 30 mg/100 mL, an initial RANI concentration of 40 mg/L, a solution pH of 7.4 and a time of 75 min. These results were attributed to the important role of the photogenerated holes and photogenerated electrons over the synthesized catalyst and their generation can be induced only in the presence of simulated sunlight. The photodegradation process of RANI by Ag2O@Y Zeo followed the pseudo-first-order kinetic model and O2°- was the main reactive species.

Synergistic Adsorption-Photocatalytic Degradation of Methyl Green by Magnetic Fe3O4/CMC@Cysteine-ZnO Nanocomposite

Synergistic Adsorption-Photocatalytic Degradation of Methyl Green by Magnetic Fe3O4/CMC@Cysteine-ZnO Nanocomposite