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In this research work we report Gum-ghatti supported ZnSe-WO 3 nano-hetero-assembly for solar powered degradation of endocrine disruptor Bisphenol S (BPA). The photocatalyst was characterized by Scanning electron microscopy (SEM), High resolution transmission electron microscopy (HRTEM), Small area electron diffraction (SAED), X-Ray diffraction (XRD), Fourier transform infra red spectroscopy (FTIR), Photoluminescence (PL), Energy dispersive X-ray (EDX), UV–vis spectrophotometry and Brauner Emmet Teller surface area analyzer (BET). We achieve a Z-scheme photocatalyst (ZnSe-WO 3 ) with a higher charge flow and visible absorption. Gum ghatti acts as a superadsorbent and a sink for charge carriers. The removal of BPA has been studied under three experimental protocols where 99.5% removal was achieved by symbiose of photocatalysis-adsorption-ozonation in just 45 min hetero-assembly has a high surface area, stability and reduced carrier recombination. The results have been analyzed by scavenger effect, mass spectrometry, kinetics and total organic carbon (TOC) analysis. 49.4% of TOC was removed and COD was reduced to 16.7% after 2 h in symbiotic condition. From the band edges and scavenger effect it was inferred that superoxide radical anions are major attacking species. The work paves way for designing of novel photocatalysts with increasing biogenic quotient and higher efficiency. [ABSTRACT FROM AUTHOR]

Examination of highly proficient photoactive materials for the degradation of antibiotics from the aqueous solution is the need of the hour. In the present study, a 2D/2D binary junction GCM, formed between graphitic-carbon nitride (g-C 3 N 4) and molybdenum disulphide (MoS 2), was synthesized using facile hydrothermal method and its photo-efficacy was tested for the degradation of sulfasalazine (SUL) from aqueous solution under visible-light irradiation. Morphological analysis indicated the nanosheets arrangement of MoS 2 and g-C 3 N 4. The visible-light driven experiments indicated that 97% antibiotic was degraded by GCM-30% within 90 min which was found to be quite high than pristine g-C 3 N 4 and MoS 2 at solution pH of 6, GCM-30% dose of 20 mg, and SUL concentration of 20 mgL−1. The degradation performance of GCM-30% was selectively improved due to enhanced visible-light absorption, high charge carrier separation, and high redox ability of the photogenerated charges which was induced by the effective Z-scheme 2D/2D heterojunction formed between g-C 3 N 4 and MoS 2. The reactive radicals as determined by the scavenging study were •O 2 −, and h+. A detailed degradation mechanism of SUL by GCM-30% was also predicted based on the detailed examination of the band gaps of g-C 3 N 4 and MoS 2. [Display omitted] • 2D/2D layered heterojunction of g-C 3 N 4 /MoS 2 showed high degradation performance. • Sulfasalazine degradation was high for consecutive adsorption-photodegradation. • Proper alignment of MoS 2 and g-C 3 N 4 in heterojunction enhanced degradation rate. • Effective & sufficient production of reactive radicals enhanced the removal rate. [ABSTRACT FROM AUTHOR]

Herein, we report the designing of a C3N4/BiOI heterostructure that is supported on gum acacia-crosslinked-poly(acrylamide) hydrogel to fabricate a novel nanocomposite hydrogel. The potential application of the obtained nanocomposite hydrogel to remediate crystal violet dye (CVD) in an aqueous solution was explored. The structural and functional analysis of the nanocomposite hydrogel was performed by FTIR (Fourier transform infrared spectroscopy), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The different reaction parameters, such as CVD concentration, nanocomposite hydrogel dosage, and working pH, were optimized. The C3N4/BiOI heterostructure of the nanocomposite hydrogel depicts Z-scheme as the potential photocatalytic mechanism for the photodegradation of CVD. The degradation of CVD was also specified in terms of COD and HR-MS analysis was carried to demonstrate the major degradation pathways. [ABSTRACT FROM AUTHOR]

Healthy environment is necessary for growth and development of every living being. The deterioration of ecosystems due to discharge of inorganic and organic pollutants from different industries is one of the major problems. The major impact of these sources has been on our water resources. The literature studies revealed that from the age's humans are using various natural and synthetic materials for water purification. With Gradual development, these materials are modified and newer alternative materials are searched and fabricated. The present study relates to fabrication of novel Gum arabic-crosslinked-poly(acrylamide)/Ni(OH) 2 /FeOOH nanocomposite hydrogel (GA-cl-poly(AAm)/Ni(OH) 2 /FeOOH NCH) using simple copolymerization technique. The structural analysis of GA-cl-poly(AAm)/Ni(OH) 2 /FeOOH NCH was performed by employing diverse modern analytical instrumentations such as transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The HRTEM and SEM micrographs clearly demonstrated the engulfment of Ni(OH) 2 and FeOOH particles within the nanohydrogel matrix. The photocatalytic performance of synthesized GA- cl -poly(AAm)/Ni(OH) 2 /FeOOH NCH was investigated for photodegradation of methylene blue dye. All the parameters such as contact time, pH, concentration of methylene blue, NCH dosage and concentration of H 2 O 2 were optimized. It was noted that 75% methylene blue was degraded at optimized condition using GA- cl -poly(AAm)/Ni(OH) 2 /FeOOH NCH in presence of H 2 O 2. Image 1056 • Gum Arabic-crosslinked-poly(acrylamide)/Ni(OH) 2 /FeOOH nanocomposite hydrogel was synthesized using copolymerization technique. • This nanocomposite hydrogel was used for the photodegradation of Methylene blue dye. • 75% methylene blue dye was degraded at optimized condition. • Efficient photocatalytic activity was observed even after 5 successive reuse. [ABSTRACT FROM AUTHOR]

The industry is looking for new materials which can respond to specific applications that exclusively advance materials can provide. In this context, nanoparticles and nanocomposites opened an interesting method for designing specific properties which can be modulated according to the requirements. The preparation of biomolecules supported trimetallic nanoparticles and some other derives is a good example of the complex systems that can be designed for getting exclusive properties. This study is based on the preparation of new cyclodextrin supported Fe/La/Zn trimetallic nanocomposite by the microemulsion technique. Photocatalytic degradation of amoxicillin was performed using cyclodextrin-Fe/La/Zn. 78% of amoxicillin photodegradation along 4 hours of photoirradiation was achieved. Finally, the catalytic nature of new material was explored for oxidation and esterification reactions. The present study revealed that this advanced multifunctional nanomaterial can be successfully employed for environmental remediation and catalytic activities. [ABSTRACT FROM AUTHOR]

Abstract Rational designing of metal-free carbon nitride based photocatalysts can lead to an excellent optical response and a higher photocatalytic activity driven by visible and solar light. This combines green photocatalytic technology with greener materials prepared by facile approaches for environmental remediation. Herein we report utilization of star photocatalyst g-C 3 N 4 (CN) to form highly efficient hetero-assemblies along with acidified g-C 3 N 4 (ACN), polyaniline (PANI), reduced graphene oxide (RGO) and biochar. By use of these organic semiconductors we synthesize g-C 3 N 4 /ACN/RGO@Biochar (GARB), g-C 3 N 4 /PANI/RGO@Biochar (GPRB) and ACN/PANI/RGO@Biochar (APRB) nano-assemblies with different optical response and band edge positions for a better charge flow and reduced recombination of carriers. These synthesized catalysts were used for visible light powered degradation of 2,4-Dichlorophenoxy acetic acid (2,4-D) and ibuprofen (IBN). APRB performs the best and degrades 99.7% and 98.4% of 2,4-D and IBN (20 mg L−1) under Xe lamp exposure in 50 min and retention of high activity in natural sunlight. Optical analysis, photoelectrochemical response and radical quenching studies show both hydroxyl and superoxide radical anions as major reactive species and a Z-scheme photocatalytic mechanism. RGO acts as an electron mediator and protects higher positioned bands of PANI and ACN in APRB for a remarkable photocatalytic activity for a metal free material. The degradation pathway was analyzed by LC-MS analysis and 42% and 40% total organic carbon was removed in 2 h for 2,4-D and IBN degradation respectively. The toxicity of degraded products was analyzed by analyzing viability of human peripheral blood cells with retaining of 99.1% cells. Graphical abstract Image 1 Highlights • Metal free organic semiconductors based nano-assemblies as photocatalysts. • Utilizing g-C 3 N 4 , acidified C 3 N 4 , PANI for designing efficient photocatalyst. • Z-scheme mechanism-high spectral response and charge separation. • Excellent photo-degradation of Ibuprofen and 2,4-D under artificial and solar light. • Complete mineralization and no toxicity on human PBL cells. [ABSTRACT FROM AUTHOR]

Currently, the photocatalytic nanomaterials performing under solar radiation have gained worldwide attentions due to increasing environmental deterioration. For utilizing the sunlight for degradation of emerging pollutants it is important to develop visible active photocatalysts. This laboratory scale work reports magnetic and optically active nano-photocatalyst Fe x Zn 1−x O(x = 0.01, 0.03, 0.05) synthesized by solution combustion method. High resolution transmission microscopy suggests a slight degradation in the crystallite structure with Fe doping. X-ray photoelectron spectroscopy analysis shows the presence of intrinsic defects in the crystal structure. Zn resides in +2 and and Fe in +3 oxidation state. Optical band gap studies were made with band structure for each doped sample. The photoctalytic activity of the samples was tested by solar degradation of noxious pollutant Bisphenol A. 99.1% of bisphenol was degraded in 90min in presence of Fe 0.03 Zn 0.97 O under synergistic adsorption and photocatalysis. The results were analyzed in terms of total organic carbon, chemical oxygen demand, effect of scavengers, gas chromatography-mass spectrometry and reusability. In presence of Fe 0.03 Zn 0.97 O, 45.3% of total organic carbon was removed and chemical oxygen demand was reduced to 11.2%. A possible mechanism with structures of the intermediates has been given. Effect of scavengers reveal that hydroxyl radicals are major reactive oxygen species involved which is also supported by the band edge positions. The research work promises to design highly photo-active tuneable magnetic photocatalysts for solar powered degradation of contaminants of emerging concern with a simple and cost-effective approach. [ABSTRACT FROM AUTHOR]

Water contaminated by oil, dyes and micropollutant as Bisphenol A (BPA) pose challenges to the management of water resources. In this small scale laboratory experiment we report the synthesis of superparamagnetic iron-oxide nanoparticles (SPION) and their nanocomposite with β-cyclodextrin (SPION/β-CD). Fourier transform infra red spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), high resolution transmission electron microscopy (HRTEM), small area electron diffraction (SAED), photoluminescence (PL), UV–vis spectroscopy, Mossbauer and vibrating sample magnetometry (VSM). Visible light assisted photo-oxidation of BPA was investigated in presence of SPION and SPION/β-CD. The treatment performances were evaluated in terms of BPA degradation using UV–visible spectrophotometer, gas chromatography–mass spectrometry (GC–MS), total organic carbon analysis (TOC), chemical oxygen demand analysis (COD) and CO 2 emission. 82.55% degradation was achieved through photodegradation under solar illumination. The magnetic nanocomposite was capable of scavenging oil from water as determined from oil sorption studies and magnetic separation thereof. An oil retention capacity of 7.2 g/g of nanocomposite has been observed. In addition 94.22% degradation of Malachite Green dye was also achieved in a 2 h sunlight driven photocatalysis process. Interestingly, the higher removal efficiency and reusability studies confirm the suitability for oil spill remediation. Magnetically recoverable, photocatalytic, bio-compatible nanocomposite of SPION and with β-cyclodextrin were prepared by the simple technique and utilized for multi pollutant removal and has a higher reusability and potential biomedical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Water pollution via hazardous organic pollutants poses a high threat to the environment and globally imperils aquatic life and human health. Therefore, the elimination of toxic organic waste from water sources is vital to ensure a healthy green environment. In the current work, we synthesized α-MnO 2 -Fe 3 O 4 3D-flower like structure using a two-step hydrothermal method and explored the combination in a visible-light-assisted photocatalytic degrdation of dyes. The attained high specific surface area of 82 m2/g with mesoporous nature of α-MnO 2 and Fe 3 O 4 together can generate more active sites after exposure to visible light, leading to remarkable photodegradation performance. Significantly, twofold higher dye (methylene blue, MB (94.8%/120 min; crystal violet, CV (93.7%/120 min)) and drug (LVO 91%/90 min) photodegradations were observed with α-MnO 2 -Fe 3 O 4 as catalyst than pure α-MnO 2 and Fe 3 O 4 at pH 6, respectively. This is attributed to the higher surface area and synergistic effect between Mn and Fe. More than 85% stability was observed with optimized catalysts employing MB and CV dyes, demonstrating the excellent reusability of the α-MnO 2 -Fe 3 O 4. The underlying mechanism indicates that the formation of reactive oxygen species predominantly plays a role in the photodegradation of dyes under visible light. Consequently, these new insights will shed light on the practical applications of the α-MnO 2 -Fe 3 O 4 3D-flower-like spherical structure for eco-friendly remediation via wastewater treatment. [ABSTRACT FROM AUTHOR]

The development of multifunctional materials, specially nanocomposites, exhibit new and interesting properties which can extend the applicability ranges to diverse fields. In this way, the use of tri metallic nanoparticles, and derives, demonstrated higher efficacy for purification, catalytic activities and as antibacterial agents. This work is concentrated on the fabrication of Fe/La/Zn trimetallic nanoparticles (TNPs) and Fe/La/Zn@GO trimetallic nanocomposite (TNC) using the micro-emulsion method, specially indicated as photocatalysts for remediation of the organic pollutant. An intense characterization was performed by employing techniques as scanning electron microscopy (SEM), X-Ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). The potential applications of the Fe/La/Zn TNPs and Fe/La/Zn@GO TNC were explored for the photodegradation of phenylhydrazine in the presences of sunlight. Furthermore, the photocatalytic studies were performed under different conditions: (a) adsorption (in dark) followed by photocatalysis, and (b) simultaneously adsorptional-photocatalysis straight way in sunlight. It was observed that a reduction of 52% and 57.91% was achieved under sunlight using Fe/La/Zn TNPs and Fe/La/Zn@GO TNC, respectively. The optical band gap of Fe/La/Zn TNPs, and Fe/La/Zn@GO TNCs was found 2.73 eV and 2.30 eV, which lies in semiconductor region. On the other hand, the antimicrobial nature of TNPs and TNC was checked for E. coli and S. aureus. The inhibition zone exhibited a maximum at 150 μg/mL for Fe/La/Zn TNPs (19 mm), and Fe/La/Zn@GO TNC (17 mm). This study revealed that resulting materials can be defined as a novel class of advanced multifunctional materials which can be employed effectively for environmental remediation and antimicrobial studies. Unlabelled Image • Synthesis of Fe/La/Zn trimetallic nanoparticles (TNPs) and Fe/La/Zn@GO trimetallic nanocomposite (TNC) by micro emulsion way • Photodegradation of phenylhydrazine using Fe/La/Zn trimetallic nanoparticles and Fe/La/Zn@GO trimetallic nanocomposite • Photodegradation of 52% and 57.91% was achieved using Fe/La/Zn TNPs and Fe/La/Zn@GO TNC, respectively. • The optical band gap of Fe/La/Zn TNPs and Fe/La/Zn@GO TNCs was found to be 2.73 eV and 2.30 eV. • Antimicrobial nature of TNPs and TNC was checked beside E. coli and S. aureus. [ABSTRACT FROM AUTHOR]

Abstract Novel Zr 2 Ni 1 Cu 7 trimetallic nano-alloy (TNA) and Zr 2 Ni 1 Cu 7 /Si 3 N 4 trimetallic nano-alloy composite (TNAC) have been successfully prepared by facile microwave reduction method. The synthesis of TNA and TNAC was ascertained by characterizing them by using various techniques such as SEM, TEM, XRD, EDX and FTIR etc. The EDX shows the presence of all constituents in TNA and TNAC. The XRD study demonstrated the crystalline and semi-crystalline nature of TNA and TNAC. The optical band gap study revealed that TNAC (2.47 eV) has lower band gap then TNA (2.54 eV). The visible light photocatalytic activity of Zr 2 Ni 1 Cu 7 TNA and Zr 2 Ni 1 Cu 7 /Si 3 N 4 TNAC has been successfully utilized for the photodegradation of methylene blue (MB). The presence of H 2 O 2 has been found to influence the photodegradation rate. Photodegradation results presented that maximum degradation was observed in the presence of H 2 O 2 and Zr 2 Ni 1 Cu 7 TNAC (92%). Scavenging activity has revealed that the hydroxyl radicals were the major reacting species. These species successfully degraded the MB into various intermediates that has successfully been determined by the LC-MS. Kinetic studies indicated that the degradation of MB by Zr 2 Ni 1 Cu 7 TNA and Zr 2 Ni 1 Cu 7 /Si 3 N 4 TNAC followed pseudo-first-order kinetics. Graphical abstract Unlabelled Image Highlights • Zr 2 Ni 1 Cu 7 TNA and Zr 2 Ni 1 Cu 7 /Si 3 N 4 TNAC synthesized by facile microwave reduction method. • Synthesis of TNA and TNAC were ascertained by characterizing them with SEM, TEM, XRD, EDX and FTIR. • The optical band gap study revealed that TNAC(2.47 eV) has lower band gap then TNA (2.54 eV) • TNA and TNAC were successfully employed for the photodegradation of methylene blue. [ABSTRACT FROM AUTHOR]

In the present work, we synthesized La/Cu/Zr trimetallic nanoparticles (TNPs) by microwave method, which is applied as an effective nanophotocatalyst for the removal of a ampicillin antibiotic from aqueous media. The prepared nanomaterial was characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The experimental results showed that prepared nanoparticles have high photodegradation tendency for the removal of ampicillin antibiotic from the aqueous solution. The pseudo-first-order equation represents the better kinetics of the photocatalytic process. The feasibility of ampicillin antibiotic adsorption onto La/Cu/Zr TNPs was also studied and the results showed that the adsorption was supported with spontaneous photodegradation process. A photocatalytic degradation 86% of the antibiotic has been observed. [ABSTRACT FROM AUTHOR]

The development of novel visible powered nano-heterojunctions with multi-pronged capabilities for environmental and catalytic applications has been gaining importance for persistent pollutant degradation & clean energy production. A magnetically recoverable biochar supported ternary g-C 3 N 4 /Bi 2 O 2 CO 3 /CoFe 2 O 4 heterojunction (BCBF) was fabricated which shows a high visible photoactivity. The heterojunction was used for degradation of pesticide paraquat under visible radiation (Xe lamp), natural sunlight, photo-ozonation, peroxymonosulphate, and coupled conditions. A high degradation of 99.3% was achieved under visible radiation in 90 min and 92.1% under solar light in 120 min. Biochar supported ternary junction performs manifold faster than Bi 2 O 2 CO 3 /CoFe 2 O 4 , g-C 3 N 4 /CoFe 2 O 4 , g-C 3 N 4 /CoFe 2 O 4 , Bi 2 O 2 CO 3 (BOC), CoFe 2 O 4 (CF) and g-C 3 N 4 (CN). The effect of operational parameters as effect of pH, H 2 O 2 , anions, ozone and peroxymonosulphate (PMS) was also studied. In BCBF + PMS + O 3  + Vis protocol a spectacular complete degradation was observed in less than 30 min. Ternary band structure efficiently reduces the charge recombination rate and promotes spectral activity which was confirmed by photoluminescence, photocurrent response and EIS analysis. By LC-MS, scavenging experiments and ESR studies a possible mechanism was also proposed. Cyto-toxicity studies of degraded products on human peripheral blood cells revealed almost 99% cell viability affirming the complete mineralization. The junction was also used for reduction of 4-nitrophenol into 4-aminophenol with complete conversion in less than 5 min with rate constant 13.05 × 10 −3  s −1 . In addition the ternary junction shows a high visible powered conversion of CO 2 producing CH 4 (∼119 µmol g −1 ), CO (∼131 µmol g −1 ) and O 2 (∼242 µmol g −1 ) with a high rate constant of 13.05 × 10 −3  s −1 . [ABSTRACT FROM AUTHOR]

Novel magnetic quaternary BiOCl/g-C 3 N 4 /Cu 2 O/Fe 3 O 4 (BGC-F) nano-heterojunction with excellent photocatalytic activity was prepared by facile co-precipitation method. The visible photodegradation activity of the junction was analyzed for sulfamethoxazole (SME) as target pollutant. BGC-F with a dosage of 0.2 g L −1 exhibits high photocatalytic activity with 99.5% of SME (100 µM) degraded in 60 min under visible (Xe) lamp and 92.1% in 120 min under natural sunlight. The activity of quaternary junction was found to be 7.2, 6.8 and 4.2-fold higher as compared to C 3 N 4 /BiOCl/Fe 3 O 4 , Cu 2 O/BiOCl/Fe 3 O 4 and Cu 2 O/BiOCl/C 3 N 4 junctions respectively. Formation of an effective p-n-p junction (BiOCl-C 3 N 4 -Cu 2 O) leads to shifting of energy bands and rising of an in-built electric field and charge separation. The effect of parameters as pH, catalysts loading amount, NO 3 − and HCO 3 − have been studied. The O 2 − and OH was found to be major reactive species identified by scavenging experiments and the band gap structure analysis The results for mineralization were analyzed in terms of Liquid chromatography-mass spectroscopy (LC-MS), total organic carbon (TOC) removal and chemical oxygen demand (COD). 41.6% of TOC was removed in 3 h experiment under Xe lamp exposure. The drug degradation was also confirmed by testing activity on E. coli and cyto-toxicity on human peripheral blood lymphocytes (PBL). Only 2.1 mm zone of inhibition was observed for E. coli in case of exposure to SME degraded products while for pure SME it was 18.1 mm hinting complete mineralization. In addition 99% cell viability was observed for PBL cells treated with degraded products of SME. Furthermore, BGC-F exhibited good reusability after magnetic separation and regeneration, rendering it a promising multi-functional catalyst with active use of advanced oxidation processes for treating pharmaceutical waste water. [ABSTRACT FROM AUTHOR]

In this research work we report synthesis of g-C 3 N 4 /FeVO 4 (CI) and g-C 3 N 4 /FeVO 4 /Fe@NH 2 -Biochar (CIB) nano-hetero assemblies for removal of methyl paraben (MeP) and 2-cholrophenol (2-CP) via adsorption, photocatalysis and photo-ozonation. CI and CIB have been characterized by FT-IR, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), UV–Vis spectroscopy, photoluminescence (PL), vibrating sample magnetometry (VSM), Brauner-Emmet Teller surface area analyzer (BET). CIB shows good photocatalytic activity owing to higher specific area, nanosheet porous structure, stability, broader solar spectrum response and reduced charge carriers recombination. Fe@NH 2 -biochar facilitates the degradation via high adsorption capability due to reduced recombination, better charge separation, adsorption and acting of biochar as sink of electrons. The CIB photocatalytic system was tested under three experimental conditions for photodegradation of MeP and 2-CP; adsorption followed by photo-degradation (AP); simultaneous adsorption and photocatalysis (SAP); SAP + O 3 . An apparent synergism between adsorption, photocatalysis and photo-ozonation brings out excellent and promising results. 98.4% of MeP and 90.7% of CP degradation was achieved under simultaneous adsorption and photocatalysis in presence of CIB. The results were analyzed in terms of reaction kinetics, adsorption isotherms, scavenger effect, liquid chromatography-mass spectrometry (LC-MS), Total Organic Carbon (TOC) analysis and cytotoxicity analysis of treated water. An efficient TOC removal 74.2 & 73.9% for MeP and 2-CP were respectively achieved under SAP + O 3 +CIB photocatalysis system. Degradation pathways have been proposed for degradation of MeP and CP thorough photo-degradation and photo-ozonation. The cyto-toxicity studies on Human peripheral blood lymphocytes provide a reference for removal of noxious pollutants in real systems. This experimental work paves a way to design tuneable simple junctions for photocatalytic applications by utilizing various experimental protocols. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis of a metal-free coal-char supported polymeric g-C3N4/RGO (RPC) nano-photocatalyst for the efficient solar powered degradation of the noxious emerging pollutants ciprofloxacin (CIF) & β-estradiol (ESD) and conversion of CO2 into CH4, CO & O2. RPC shows good photocatalytic and adsorption activity owing to its high surface area and reduced charge recombination rate. The photodegradation results of the treated water sample were investigated in terms of reaction kinetics, active species trapping experiments, high resolution mass spectrometry (HR-MS) and Chemical Oxygen Demand (COD) analysis. The higher solar photoactivity is attributed to the higher surface area, higher visible absorption, charge transfer, and reduced recombination. The superoxide radical anions were found to be the major active species in photodegradation, which is also supported by the band structure analysis. The catalytic activity is highly enhanced by the addition of H2O2, O2 and O3 as they facilitate the formation of radicals. The possible degradation pathways for the degradation of CIF and ESD have been proposed. This work shows promising solar-active metal-free photocatalysts for efficient environmental remediation and CO2 conversion to fuels. [ABSTRACT FROM AUTHOR]

In the present study, gelatin-Zr(IV) phosphate nanocomposite (GT/ZPNC) was synthesized by sol-gel method by mixing the gelatin gel into the inorganic part Zr (IV) phosphate (ZP). The GT/ZPNC was characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy (SEM), transmission electron micron scope (TEM), X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The photodegradation activity of GT/ZPNC was explored for the removal of methylene blue (MB) and fast green (FG) dyes from aqueous solution. It was found that 87.81% MB and 89.91% FG were degraded within five hours. Also, the kinetics of photocatalytic degradation for MB and FG was investigated via pseudo first-order kinetic model with higher regression coefficient values (R 2 ). The antimicrobial efficiency of GT/ZPNC was investigated against E. coli. [ABSTRACT FROM AUTHOR]

Herein we report synthesis of nano-hetero assembly of superparamagnetic Fe 3 O 4 and bismuth vanadate stacked on Pinus roxburghii derived biochar. Optical studies and band structure analysis indicate the hybridization between the two semiconductors facilitating photodegradation of pollutants in presence of natural sunlight. The nano-heterojunctions have been utilized for removal of emerging micro-pollutants as methylparaben (MeP). 97.4% of MeP degradation was achieved in presence of biochar/Fe 3 O 4 /BiVO 4 in 2 h. A degradation pathway has also been proposed on basis of mass spectrometry, chemical oxygen demand analysis and effects of various scavengers. Pinus derived biochar has also been utilized to see its long term effect on soil characteristics and fertility. The biochar has also been used to remove excessive pesticide from soil for lesser bioavailability. [ABSTRACT FROM AUTHOR]

The step-scheme (S-scheme) heterojunctions with superior redox capability have recently emerged as one of the most promising materials for cleaning up of contaminated environments. Herein, we synthesized g-C 3 N 4 /NiFe 2 O 4 (NFC) heterojunction photocatalyst via a hydrothermal route for the degradation of Cephalexin (CPX). The integration of g-C 3 N 4 and NiFe 2 O 4 into heterojunction with an effective S-scheme transfer which prevents the recombination of essential photoexcited electron-hole pairs leads to excellent 99.3% of photocatalytic degradation of CPX within 60 min under visible light. The scavenging experiments suggested •OH and •O 2 - radicals generated on high potential bands of S-Scheme g-C 3 N 4 /NiFe 2 O 4 as active species responsible for high performance CPX removal. The degradation intermediates were examined by Liquid Chromatography mass spectroscopy (LC-MS) and a probable pathway of CPX degradation was proposed accordingly. The inherent work function between g-C 3 N 4 and NiFe 2 O 4 leads to bending of conduction and valence bands which subsequently forms an built-in electric field across the interface facilitating the superior separation of photogenerated electrons and holes. The five subsequent recycling tests demonstrated the catalyst's strong photocatalytic stability and the easy recovery process because of its magnetic characteristic. This research may bring fresh insights for constructing magnetic photocatalysts based on g-C 3 N 4 , which are both highly effective and stable. Additionally, it also paves a path for the designing of S-scheme heterojunctions with great performance for environmental remediation applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Guar gum/Al 2 O 3 (GG/AO) nanocomposite was prepared using simple and cost effective sol–gel method. This nanocomposite was characterized by several analytical techniques viz. scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermal analysis (TGA/DTA), Fourier transform infrared spectroscopy (FTIR) and ultraviolet-visible spectroscopy (UV–vis). The FTIR analysis confirmed that GG/AO composite material was formed. TEM images inferred the particle size in the range between 20 and 45 nm. GG/AO nanocomposite exhibited good photocatalytic performance for malachite green (MG) dye (dye initial concentration 1.5 × 10 −5 M) degradation from aqueous phase. The adsorption followed by photocatalysis and coupled adsorption/photocatalysis reaction achieved about 80% and 90% degradation of MG dye under solar irradiation. Antibacterial test showed the excellent activity of GG/AO nanocomposite against Staphylococcus aureus . [ABSTRACT FROM AUTHOR]

The study explored the characteristics and effectiveness of modified TiO 2 nanotubes with zeolite as a composite photocatalyst (MTNZC) for the degradation of triclocarban (TCC) from the aqueous solution. MTNZC samples have been produced via electrochemical anodisation (ECA) followed by electrophoretic deposition (EPD). Three independent factors selected include MTNZC size (0.5–1 cm2), pH (3–10), and irradiation time (10–60 min). The observation revealed that the surface of Ti substrate by the 40 V of anodisation and 3 h of calcination was covered with the array ordered, smooth and optimum elongated nanotubes with average tube length was approximately 5.1 μm. EDS analysis proved the presence of Si, Mg, Al, and Na on MTNZC due to the chemical composition present in the zeolite. The average crystallite size of TiO₂ nanotubes increased from 2.07 to 3.95 nm by increasing anodisation voltage (10, 40, and 60 V) followed by 450 °C of calcination for 1, 3, and 6 h, respectively. The optimisation by RSM shows the F-value (36.12), the p-value of all responses were less than 0.0001, and the 95% confidence level of the model by all the responses indicated the model was significant. The R2 in the range of 0.9433–0.9906 showed the suitability of the model to represent the actual relationship among the parameters. The photocatalytic degradation rate of TCC from the first and the fifth cycles were 94.2 and 77.4%, indicating the applicability of MTNZC to be used for several cycles. [Display omitted] • The characteristics of modified TiO 2 nanotubes with zeolite composite was described. • MTNZC exhibited 81.2% of the triclocarban degradation within 50 min. • The reusability of MTNZC exhibited between 94.2 and 77.4% of TCC degradation. [ABSTRACT FROM AUTHOR]

• Efficient rutile photocatalysts obtained by the reverse micelle and low temperature methods. • Monitoring of the degradation kinetics using light reflected from the TiO 2 suspension. • Effect of H 2 O 2 on the CR, MO and DR23 dyes photodegradation was evaluated. The study proposes two new TiO 2 photocatalysts with excellent photocatalytic properties obtained by the reverse micelle (RM-TiO 2) and low temperature (LT-TiO 2) methods. The crystal structure and morphology of the obtained TiO 2 samples were analyzed by X-ray diffraction, scanning electron microscopy and IR-spectroscopy. The chosen synthesis conditions lead to pure rutile modification. FTIR spectra of the obtained samples contain characteristic bands, attributed to stretching vibrations of Ti–O bonds and to deformation vibrations of Ti–OH bonds. The average crystallite sizes for RM-TiO 2 and LT-TiO 2 samples are 5.4 and 9 nm, respectively. SEM analysis showed that the RM-TiO 2 consists of TiO 2 particles, assembled into spherical aggregates, while LT-TiO 2 consists of smaller aggregates and is mostly mesoporous. The BET surface areas of the RM-TiO 2 and LT-TiO 2 samples are 39 and 63 m2/g, respectively. The photocatalytic degradation of the Congo Red (CR), Methyl Orange (MO) and Direct Red 23 (DR23) dyes in water medium has been studied under UV LED irradiation with H 2 O 2 as an auxiliary oxidant. Both the RM-TiO 2 and LT-TiO 2 samples are active photocatalysts. The optimal dosages are 1.5 and 0.5 g/L respectively. The maximum photodegradation efficiency of RM-TiO 2 is observed when the concentration of H 2 O 2 is 15 mM for CR, 5 mM for MO and 10 mM for DR23. The maximum photodegradation efficiency of LT-TiO 2 is observed when the concentration of H 2 O 2 is 10 mM for CR, 2.5 mM for MO and 1.5 mM for DR23. The boosting effect of H 2 O 2 on the degradation efficiency can be explained by an increased generation of •OH radicals. The real-time monitoring of degradation kinetics has been performed using measurements of light reflected from TiO 2 suspension. The proposed technique allows the use of small volume of solution and amount of photocatalyst. The synthesized rutile photocatalysts may be used for wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • The solvent-free ball-milling method obtains Z-scheme CeO 2 /g-C 3 N 4 heterojunction. • CeO 2 /g-C 3 N 4 thermodynamically has stronger redox potential and active radicals. • 70% CeO 2 /g-C 3 N 4 exhibited the best removal efficiency for MB photodegradation. • Synergy between adsorption and photodegradation of MB by CeO 2 /g-C 3 N 4 was identified. As a green solvent-free process, ball milling has attracted considerable attention in fabricating nanocomposites. Herein, we synthesized novel Z-scheme heterojunction CeO 2 /g-C 3 N 4 nanocomposites by simply direct ball milling CeO 2 and g-C 3 N 4 at three different mass ratios (3:7, 7:3, and 9:1). In comparison to individual CeO 2 and g-C 3 N 4 , the ball-milled nanocomposites showed stronger UV light response, higher charge carrier separation efficiency, greater photodegradation potential, higher photocurrent intensity, and faster electron transfer, indicating much better photocatalytic activity. When used as photocatalysts to remove methylene blue (MB) under UV light irradiation, 70% CeO 2 /g-C 3 N 4 exhibited the highest removal rate (90.1%), much better than that of CeO 2 (6.2%) or g-C 3 N 4 (45.7%). The synergistic interact between adsorption and photodegradation of the CeO 2 /g-C 3 N 4 nanocomposites was simulated by kinetic models, and a strong positive correlation (r = 0.834 and r s = 0.777) between adsorption and photocatalysis was identified. The results indicate that adsorption can promote photodegradation by accelerating the kinetics, while photodegradation can regenerate adsorption sites. This work provides not only a facile synthesis of Z-scheme heterojunction photocatalysts but also a novel perspective for better understanding the synergy between adsorption and photocatalysis. [ABSTRACT FROM AUTHOR]

Solar-light powered environmental detoxification is surely a promising and sustainable approach for common goals of human development and ecosystem preservation. Focussing on this, we herein report fabrication of a novel solar active heterojunction Fe 3 O 4 @SrTiO 3 /Bi 4 O 5 I 2 an in-situ hydrothermal route. The heterojunction was used for the degradation and mineralization of anti-inflammatory drug Diclofenac (DCF) as target pollutant under simulated solar-light irradiation. Current results reveal that the optimized junction displayed 98.4% diclofenac removal in 90 min with 87.2% mineralization. The ESR probe suggests that both ●OH and ●O 2 − radicals are active species involved in DCF degradation. Analysing the band structure, thermodynamic feasibility and the photocatalytic performance, a traditional mechanism was ruled out and a Z-scheme transfer was predicted. The charge separation was obviously drastically improved by the Z-scheme transfer and facilitation by Fe 3 O 4 and Ti4+/Ti3+ in-built redox mediator. A degradation route was predicted on basis of intermediates detected by liquid-chromatography mass spectrometry analysis. This work promises to provide future possibilities for rational designing and fabrications of semiconductor heterojunctions for solar environmental applications. [Display omitted] • Solar active Fe 3 O 4 @SrTiO 3 /Bi 4 O 5 I 2 heterojunction formed by in-situ hydrothermal route. • High performance removal of diclofenac under simulated solar light. • Low recombination, high charge transfer capacity and photocurrent response. • Fe 3 O 4 and Ti4+/Ti3+ in-built redox for facile Z-scheme transfer. • ●OH and ●O 2 − radicals are both active species-High magnetic separation [ABSTRACT FROM AUTHOR]

Rationally fabricated Z -scheme hetero-junctions with intimate interfacial contact have proven to accelerate the photocatalytic degradation of noxious pollutants by effectively suppressing the recombination and promoting charges transfer rate. Herein, we report fabrication of reduced graphene oxide (RGO) modified LaTiO 2 N/Bi 2 S 3 heterojunction photocatalyst by sovothermal route. The microstructure analysis, structure determination, electronic and optical analysis of as prepared photocatalysts was done by using multiple techniques. The Z -scheme LaTiO 2 N/Bi 2 S 3 @RGO (LBR) photocatalyst shows remarkable performance for photo-degradation of tetracycline (TC) under visible light. 96.4% TC was eliminated within 90 min under visible light with ~100% removal in 60 min under full spectrum irradiation. In addition the heterojunction shows 80.2% TC removal under natural sunlight irradiation. The TC degradation with LBR heterojunction is ~9 times faster than bare Bi 2 S 3. The Z -scheme transfer follows the route as Bi 2 S 3 → RGO → LaTiO 2 N and provides a swift path for movement of electrons from CB of LaTiO 2 N to VB of Bi 2 S 3. The possible degradation route of TC has also been proposed based on quenching experiments and identification of degradation intermediates by Liquid chromatography-mass spectrometry (LC-MS). The quenching experiments reveal that O 2 – radicals are the main active species involved followed by OH radicals which has been explained by thermodynamic feasibility of their production from the junction arrangement. The mechanism has been explained by Z -scheme transfer by comparing to the conventional type-II junction. The enhancement in photocatalytic activity is primarily attributed to Z-scheme charge transfer between LaTiO 2 N and Bi 2 S 3 facilitated by reduced graphene oxide sheet via strong interfacial contact maintaining high potential for redox conversions. The recycling experiments reveal the stability and reusability of the LBR hybrid photocatalyst with ability to perform under sunlight. The novel nitrides-phosphide based junction with improved properties for visible and solar photocatalytic activity provides future prospects in forming superior hetero-structures for environmental remediation. Unlabelled Image • LaTiO 2 N/Bi 2 S 3 @RGO heterojunction photocatalyst fabrication by simple solvothermal route. • High performance degradation of tetracycline-visible, full spectrum and sunlight • Interfacial charge transfer capacity-internal electric field–higher spectral capture. • Z-scheme and RGO lead to high charge separation, high redox capability, stability. • Thermodynamic feasibility and experimental findings suggest Z-scheme over conventional type-II transfer. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride based photocatalytic materials have proved to be one of most promising candidates for hazardous pollutant removal and clean energy production. Structural modification and engineering of various materials based on g-C 3 N 4 have been attempted to achieve solar energy harvesting, slow charge transfer and efficiency. Here we report synthesis of all metal free self-assembled carbon quantum dots and reduced graphene oxide layers modified S@g-C 3 N 4 /B@g-C 3 N 4 (CRSB) photocatalyst for visible and solar degradation of chloramphenicol (CMP) (10 mg L−1). Differently doped g-C 3 N 4 with different band structure forms a junction which grows into an effective Z -scheme photocatalyst. Extended visible absorption is achieved with optimized modification by reduced graphene oxide (RGO) and carbon quantum dots. The optical response, band structure and charge separation efficiency were tested by optical absorption, electrochemical impedance, Mott-Schottky plots and photo-luminescence. CQDs convert a typical type-II mechanism into effective Z -scheme transfer. For the best sample CRSB 99.1% CMP was photo-degraded in 90 min exposure to visible light and retention of high activity in natural solar light (92.4% in 120 min). A stable heterojunction has been attempted to design using boron doped g-C 3 N 4 and sulphur doped g-C 3 N 4 with different band positions via ratio optimization with enhanced charge transfer. The degradation rate for CRSB (0.0810 min−1) is 10 times than bare g-C 3 N 4 (0.00802 min−1). The optimized combination of carbon quantum dots and RGO with intimate interfacial contact for charge flow & reduced recombination, better adsorption of pollutant, high visible absorption and production of reactive oxygen species. The effect of pH, electrolytes and water matrix was studied for CMP degradation. The mechanism of degradation and mineralization was confirmed by liquid chromatography-mass spectrometry (LC-MS) analysis, scavenging experiments and electron spin resonance. It was observed that the chances of •O 2 – and •OH radicals increased on the formation of the junction as compared to individual doped and bare carbon nitride. The mineralization was ensured by high total organic removal and cyto-toxicity studies of treated water sample onto human peripheral blood (PBL) cells with high cell viability equivalent to untreated cells. This experiment supports the competence of optimally designed metal free and environmentally friendly cost-effective catalysts with higher photocatalytic efficiency for removal of hazardous pollutants. Unlabelled Image • S@g-C 3 N 4 and B@g-C 3 N 4 self-assembled junction • Heterojunction formed from differently doped g-C 3 N 4 • Modification by RGO and CQDs- All metal free catalyst • Intimate charge transfer at the interface-low recombination • Excellent visible and solar degradation of chloramphenicol • High mineralization-no toxicity on human blood cells [ABSTRACT FROM AUTHOR]