Search

In the present work, we report the preparatory strategy of MgCr-layered double hydroxide (LDH) nanosheets with 90% degree of delamination by employing a formamide-assisted co-precipitation and mild hydrothermal route for the degradation of methylene blue (MB) under solar light exposure. The as-synthesized MgCr-LDH nanosheets were characterized by assorted characterization techniques such as powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), Raman, thermogravimetric analysis (TGA), N

Design and facile fabrication of a magnetically separable hetero-structure photocatalyst as well as an adsorbent having dual green benefits towards energy conversion and pollutant remediation are quite indispensable in the current scenario. In this regard, a composite of citrate capped Fe3O4 and UiO-66-NH2 has been designed to remediate Cr (VI) by adsorption and harvest photons from visible light for clean energy (H2) conversion. The material was prepared by the union of citrate capped Fe3O4 (CCM) and versatile aqueous stable Zr-based MOF (UiO-66-NH2) through in-situ solvothermal method. The composite of CCM with MOF (MU-2) was studied through sophisticated analysis techniques; PXRD, FT-IR, BET, UV–Visible DRS, PL, TG, HRTEM and XPS etc. to reveal the inherent characteristics of the material. BET surface analysis revealed high specific surface area (572.13 m2 g−1) of MU-2 in comparison to its pristine MOF. Furthermore, the dual function composite MU-2′s VSM studies showed that its magnetic saturation is 3.07 emu g−1 that is suitable for magnetic separation after desired reaction from aqueous media. The Cr (VI) sorption studies revealed that the composite adsorbent (MU-2) showed maximum monolayer adsorption capacity (Qm) of 743 mg g−1 which followed pseudo second order kinetics. Moreover, the sorption thermodynamics revealed that the process was spontaneous and endothermic in nature. In addition to it, the synthesized composite material displayed enhanced activity towards photocatalytic H2 evolution with a maximum evolution rate of 417 µmole h−1 with an apparent conversion efficiency (ACE) of 3.12 %. Typically, MU-2 displays high adsorptions of Cr (VI) as well as some extent of Cr (VI) reduction owning to its populous active sites and free carboxylate groups respectively. Moreover, the synergistic effect of CCM and UNH in the composite resulted in Z scheme mediated charge transfer mechanism that showed enhanced H2 photo-evolution rates. Hence, MU-2 can be readily utilized as magnetically retrievable dual function composite for Cr (VI) adsorption and photocatalytic H2 evolution.

In the existing eco-crisis, designing and engineering an efficient as well as water stable photocatalyst for energy conversion and pollutant abatement remains crucial. In this regard, a mixed linker type zirconium metal organic framework (Zr-MOF) with terepthalic acid based ditopic linkers were utilized to design a single component photocatalyst through single step solvothermal method to utilize photons from visible light illumination towards hydrogen energy (H

Efficient interfacial exciton transfer and separation have been regarded as the foremost confront of semiconductor oriented photocatalysis. The simultaneous discovery of crystal facet isotype heterojunction across the (0 4 0)-reduction and (1 1 0)-oxidation facet of monoclinic scheelite BiVO4 crystal; and Schottky junction at the interfacial region of BiVO4 crystal with well-exposed functional (0 4 0) facet and r-GO sheets has been reflected as an efficient electron injection route. In this context lucrative architecture of a high productive all-solid-state Z-scheme charge transfer dynamics In2S3@r-GO@(040/110)-BiVO4 isotype ternary hybrid photocatalyst was carried out and well-validated by FESEM and HRTEM analyses. Photoelectrochemical measurements have revealed that the accumulated photo-electrons over the exposed (0 4 0)-crystal facet of BiVO4 truncated bipyramid easily cross the minor Schottky junction to expedite the unidirectional injection to the π–π conjugated two-dimensional planar r-GO structure. Besides, subsequent trapping of the injected electrons by the photoinduced holes of In2S3 leading to a superior charge carrier separation in the material, validated by PL, EIS, Mott-Schottky, and transient photocurrent analysis. Perceptibly, this intimate interfacial interacted crystal facet dependent electron shuttle provided a longer life span electrons and holes to settle in the conduction band of In2S3 and valence band of (1 1 0)-BiVO4, respectively, for elevated photo-activity efficiency. The In2S3@r-GO@(040/110)-BiVO4 ternary hybrid contributes 89.7% of Ciprofloxacin (CIP) detoxification in 150 min and 885.43 µmol of O2 evolution in 120 min. More in, the constructive interrelations of resultant Physico-chemical, photoelectrochemical, and augmented photocatalytic redox efficiency were well-illustrated. This unique association semiconductor ternary hybrid photocatalyst via metal-free mediating agent crystal-facet sandwich structure will provide a scientific innovative basis for rational design and realization of advanced Z-scheme photocatalytic system for energy and environment application.

Nitrogen reduction to ammonia is vital for chemical industries and renewable clean energy. Denying the harsh reaction conditions adopted in the Haber-Bosch process and stimulation research for ammonia production through sustainable technologies is a smart approach. Hitherto, photocatalyst acquiring the potential to attain high nitrogen reduction reaction (NRR) efficiency is a challenging task. Here, this study demonstrated cobalt titanate (CoTiO

Environmental pollution and energy scarcity is a major issue of the current scenario which forbear the progress of developing world. To overcome these problems towards a sustainable future, the utilization of sunlight by means of photocatalysis can be regarded as a best and suitable pathway. To validate this purpose, design and development of efficient heterogeneous photocatalyst for harvesting solar energy should be the major research concern for scientific community. In this regard herein, we have prepared a series of stable and efficient CoTiO3/UiO-66-NH2 p-n junction mediated heterogeneous photocatalyst by hydrothermal method. The functionalised linker of UiO-66-NH2 provided an intimate interfacial contact with CoTiO3 by Co/Ti O N ionic interaction, as proved by HRTEM and XPS analysis. Moreover the inverted V-shaped Mott-Schottky plot confirmed the junction formation in the optimised CoTiO3/UiO-66-NH2 material. In addition, EIS and PL analysis also provides sufficient evidence about the hindrance of active species recombination in composite as a result of p-n hetero junction. LC-MS characterization technique traces the assorted intermediate species produced in the course of photodegradation of Norfloxacin and confirms its complete degradation to corresponding CO2, H2O and NH4+ by the optimised CoTiO3/UiO-66-NH2. The highest photo-catalytic activity obtained towards Norfloxacin degradation is 90.13% and H2 production is 530.87 µmol in 1 h. The enhanced photo-catalytic reaction follows Type-II p-n hetero junction charge transfer mechanism and thus, paves a new way to design MOF based heterojunction photocatalyst for diverse photo catalytic performance.

Antibiotic contaminants have received much attention due to the increasing serious environmental concerns. In this work, for the first time, we have fabricated a series of significant type-II p-n heterostructure with Z-scheme charge transfer between p-type B-doped g-C3N4 with different proportion of n-type BN through a simple in-situ growth process. PXRD, FTIR, UV–Vis, FESEM, HRTEM and EIS analysis were applied for the detailed characterization of the as-prepared composites to study the crystal phase, structural features, optical and electrical properties. The photocatalytic behaviour of BN/BCN photocatalyst was investigated by the degradation of tetracycline hydrochloride under solar light illumination. Experimental results revealed that about 88.1% of TCH was degraded by the BN/BCN composite containing 4 wt% BN in the BN/BCN matrix, in 60 min of solar light irradiation. Reduction in recombination rate of photo generated electron-hole pair’s and enhanced visible light absorption ability is credited to the enhanced photocatalytic performance of BN/BCN composite. Trapping experiment for the scavenging agents has confirmed that superoxide ( O2¯) and hydroxyl (OH ) radicals are the main reactive species during the TCH degradation process. The high stability shown by the BN/BCN composite opens a new path for designing of significant BN based Z-scheme photocatalyst for prevention of environmental issues.

Perception of surface plasmonic resonance in heterogeneous photocatalysis not only has impact on basic science of sustainable energy development, but also generates green technologies for wastewater treatment, selective oxidation and reduction reactions. In the present study Au/Pd bimetallic alloyed nanoparticles were effectively decorated on mesoporous silica modified g-C3N4 (graphitic carbon nitride) nanosheets by a simple one-pot calcinations strategy. The formation of Au/Pd alloyed nanoparticles has been supported by XRD, UV–vis DRS, TEM and XPS studies. The photocatalytic performance of the photocatalysts were investigated by performing tandem reaction for simultaneous oxidation of phenol and reduction of Cr (VI). The photocatalytic performances were found to be significant for either single phenol species or single Cr (VI), but quite appreciable photocatalytic performance was observed for a solution containing Cr (VI)–phenol mixture. The synergetic effect of Au/Pd alloyed nanoparticle and enhanced photocurrent (1.4 mA/cm2) generated by the nano-composite further supports the activity. The results of tandem reaction not only reveals the feasibility of carrying out degradation of two important pollutants simultaneously from waste water, but also gives us an enlightenment to efficiently degrade mixture of pollutants without using any additional chemical as trapping agent in the photocatalytic process.

The charge separation and transfer are the major issues dominating the under-laying energy conversion mechanism for photocatalytic system. Construction of semiconductor-based heterojunction system considered to be viable option for boosting the spatial charge separation and transfer in the photocatalytic water splitting system. Here, we design a ternary heterojunction of Ti

The production of Hydrogen energy through the splitting of water is a promising pathway for clean environment and sustainability. Herein we have synthesized a series of ZnFe2O4 (ZFO)@Reduced Graphene Oxide (RGO) nanocomposites by hydrothermal followed by calcination method and studied its application towards hydrogen energy production and ciprofloxacin degradation. Powder X-ray diffraction (XRD) study and X-ray photoelectron spectroscopy (XPS) analysis indicate the good crystallinity and suitable chemical environment for the photocatalytic process. Among all the samples, ZFO@3%RGO showed 73.4% of CIP degradation under solar irradiation of 1 h, which is 1.67 times higher than that of pure ZFO nanoparticles. CIP degradation process follows first order kinetics with a good rate constant of 0.021 min−1 which is 2.3 times greater than ZFO. The photocatalyst ZFO@3%RGO illustrated maximum H2 energy production i.e. 410.32 μmol/h, which is 1.35 times more than that of neat ZFO nanoparticles. ZFO@3%RGO demonstrates the highest photocurrent density of 0.6 mA/cm2 under light illuminations, which is 250 times superior to that of the pristine photocatalyst. Bode phase analysis confirmed that ZFO@RGO shows 13 times higher charge separation efficiency in comparison to neat ZFO. The best photocatalytic activity of ZFO@3%RGO nanocomposite is due to its high light absorption capacity, low photogenerated exciton recombination, high electron-hole separation, and high photocurrent density.

To conquer the issues of poor compatibility, confined intimate contact and limited improvement of charge anti-recombination process of a traditional heterojunction formed by interfacing of two different semiconductors, a simplistic strategy has been espoused for the fabrication of isotype heterojunction flanked with two dissimilar crystal phases of a single semiconducting material. Herein, we account the fabrication of an in-situ formed M-BiVO4/T-BiVO4 (MT-BiVO4) isotype heterojunction by a simple co-precipitation method followed by altering the calcinations temperatures. The physico-chemical properties of the fabricated MT-BiVO4 isotype hetrojunctions were analyzed by using X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV–Visible Diffuse reflectance spectroscopy (UV–Vis DRS) techniques. The FESEM image of MT-BiVO4 photodeposited by Au and MnOx particles was provided strong evidence for the spatial separation of photogenerated charge carriers between M and T phase of BiVO4 in an isotype heterojunction. The interfacing of T-BiVO4 with M-BiVO4 in an isotype heterojunction affords the well-built close contact between them was confirmed by the High resolution transmission electron microscopy (HRTEM) analysis. The photocatalytic reactions of all the prepared MT-BiVO4 isotype heterojunctions were examined by monitoring the degradation of Norfloxacine and oxygen evolution reaction under visible light irradiation. The optimized 65% MT-BiVO4 isotype heterojunction discloses higher photocatalytic activity around 91% of Norfloxacine degradation in 150 min and 808 µmol of O2 evolution in 2 h under visible light irradiation. On the other hand, the photoelectrochemical measurements reveals that the optimized 65% MT-BiVO4 isotype heterojunction exhibits superior photocurrent i.e. 584 µA/cm2 which is approximately 5.1 and 25.3 times higher than the neat T-BiVO4 and M-BiVO4, and these results are well consistent with the photocatalytic activities. The higher PEC and photocatalytic activities are due to the well-built close contact, superior compatibility and matching band structure between T-BiVO4 and M-BiVO4, which provides strapping driving force for the efficient enhancement of charge separation process. The Electrochemical impedance spectroscopy (EIS), photoluminescence (PL), photoelectrochemical (PEC) and bode analysis confirms the effectual diminish of charge recombination process in MT-BiVO4 isotype heterojunction relative to the neat materials. The chronoamperometric analysis authenticated that the isotype heterojunctions are more stable than the neat materials.

Development of highly efficient robust catalyst for pollutant abetment still remains an ongoing scientific challenge in the field of visible light driven photocatalysis. In this work a series of ZnFe2O4 (ZFO)/carbon derivatives (ZFO@CNT, ZFO@GO, ZFO@Fullerene) nanocomposite were fabricated by one-pot hydrothermal method followed by calcination. The detail anatomical featured such as crystal geometry, morphology, elemental composition, light absorption performance, electron-hole recombination properties and photocurrent density were characterized by XRD, SEM, HRTEM, XPS, UV–Vis DRS, PL and electrochemical analysis respectively. The photocatalytic performances of ZFO@carbon nanocomposites were studied for the degradation of antibiotics (Norfloxacin) and hexavalent Chromium under open sun light illumination and the obtained results suggested that loading of carbon derivatives of ZFO nanoparticles enhance the visible light absorption capacity and excitation separation efficiency. Among the fabricated composites, ZFO@CNT exhibits the highest activity in comparison to other nanocomposites. The highest activity of ZFO@CNT is due to low photoexcited electron-hole recombination and high charge transfer properties of ZFO@CNT as confirmed via PL and impedance measurement. Further, the fabricated ZFO@CNT nanocomposite exhibited highest photocurrent density i.e. 2.25 mA/cm2 which was 225 times higher than that of neat ZFO. The optimal photocatalytic efficiency was shown by ZFO@CNT i.e. 91.36% degradation of 50 ppm norfloxacin and 82% reduction of 10 ppm Cr (VI) in 90 min and 60 min respectively under solar light irradiation.

Design and facile fabrication of a magnetically separable hetero-structure photocatalyst as well as an adsorbent having dual green benefits towards energy conversion and pollutant remediation are quite indispensable in the current scenario. In this regard, a composite of citrate capped Fe

Efficient interfacial exciton transfer and separation have been regarded as the foremost confront of semiconductor oriented photocatalysis. The simultaneous discovery of crystal facet isotype heterojunction across the (040)-reduction and (110)-oxidation facet of monoclinic scheelite BiVO

Environmental pollution and energy scarcity is a major issue of the current scenario which forbear the progress of developing world. To overcome these problems towards a sustainable future, the utilization of sunlight by means of photocatalysis can be regarded as a best and suitable pathway. To validate this purpose, design and development of efficient heterogeneous photocatalyst for harvesting solar energy should be the major research concern for scientific community. In this regard herein, we have prepared a series of stable and efficient CoTiO

Antibiotic contaminants have received much attention due to the increasing serious environmental concerns. In this work, for the first time, we have fabricated a series of significant type-II p-n heterostructure with Z-scheme charge transfer between p-type B-doped g-C

Fusion of heterogeneous photocatalysts with conducting polymers has paid a rising stratagem in the field of photocatalysis owing to its biocompatibility and environment friendliness. In this work a series of polypyrrole (PPY) sensitized zinc ferrite/graphitic carbon nitride (ZFCN) n-n heterojunction (ZFCN@10PPY, ZFCN@20PPY, and ZFCN@30PPY) nanocomposite were fabricated by in-situ polymerization method. Due to low band gap of polypyrrole, it behaves as a photo-sensitizer, supplies surplus numbers of electrons to ZnFe2O4/g-C3N4 n-n heterojunction and improves the photocatalytic performance. The fabricated ZFCN@20PPY exhibits highest photocatalytic activity in comparison to others nanocomposites. The superior photocatalytic performance of ZFCN@20PPY was ascribed to the tunable band structure, synergistic effect of broad absorption upto NIR region, delayed electron-hole recombination and efficient charge transfer across the junction interface which has been well confirmed from UV–Vis DRS, PL and EIS measurement. Further the photocatalytic activity of ZFCN@20PPY was supported by both n-type and p-type photocurrent density i.e. 2.4 and 3.9 mA/cm2 respectively. ZFCN@20PPY shows good photocatalytic performance towards ciprofloxacin degradation (92%) and generation of hydrogen energy (567 μmol). Along with pollutant degradation and energy production ZFCN@20PPY also shows its potential towards antibacterial activities against human pathogenic bacteria like Escherichia coli. These newly designed polymer sensitized n-n heterojunction may offer a promising strategy for maximum light absorption and be authoritative in meeting the environmental claims in the future.

The production of Hydrogen energy through the splitting of water is a promising pathway for clean environment and sustainability. Herein we have synthesized a series of ZnFe

Perception of surface plasmonic resonance in heterogeneous photocatalysis not only has impact on basic science of sustainable energy development, but also generates green technologies for wastewater treatment, selective oxidation and reduction reactions. In the present study Au/Pd bimetallic alloyed nanoparticles were effectively decorated on mesoporous silica modified g-C