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Rajput A, Nayak PK, Ghosh D, Chakraborty B. Structural and Electronic Factors behind the Electrochemical Stability of 3D-Metal Tungstates under Oxygen Evolution Reaction Conditions. ACS APPLIED MATERIALS & INTERFACES 2024; 16:28756-28770. [PMID: 38785123 DOI: 10.1021/acsami.4c07301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
Transition metal tungstates (TMTs) possess a wolframite-like lattice structure and preferably form via an electrostatic interaction between a divalent transition metal cation (MII) and an oxyanion of tungsten ([WO4]2-). A unit cell of a TMT is primarily composed of two repeating units, [MO6]oh and [WO6]oh, which are held together via several M-μ2-O-W bridging links. The bond character (ionic or covalent) of this bridging unit determines the stability of the lattice and influences the electronic structure of the bulk TMT materials. Recently, TMTs have been successfully employed as an electrode material for various applications, including electrochemical water splitting. Despite the wide electrocatalytic applications of TMTs, the study of the structure-activity correlation and electronic factors responsible for in situ structural evolution to electroactive species during electrochemical reactions is still in its infancy. Herein, a series of TMTs, MIIWVIO4 (M = Mn/Fe/Co/Ni), have been prepared and employed as electrocatalysts to study the oxygen evolution reaction (OER) under alkaline conditions and to scrutinize the role of transition metals in controlling the energetics of the formation of electroactive species. Since the [WO6]oh unit is common in the TMTs considered, the variation of the central atom of the corresponding [MO6]oh unit plays an intriguing role in controlling the electronic structure and stability of the lattice under anodic potential. Under the OER conditions, a potential-dependent structural transformation of MWO4 is noticed, where MnWO4 appears to be the most labile, whereas NiWO4 is stable up to a high anodic potential of ∼1.68 V (vs RHE). Potential-dependent hydrolytic [WO4]2- dissolution to form MOx active species, traced by in situ Raman and various spectro-/microscopic analyses, can directly be related to the electronic factors of the lattice, viz., crystal field splitting energy (CFSE) of MII in [MO6]oh, formation enthalpy (ΔHf), decomposition enthalpy (ΔHd), and Madelung factor associated with the MWO4 ionic lattice. Additionally, the magnitude of the Löwdin and Bader charges on M of the M-μ2-O-W bond is directly related to the degree of ionicity or covalency in the MWO4 lattice, which indirectly influences the electronic structure and activity. The experimental results substantiated by the computational study explain the electrochemical activity of the TMTs with the help of various structural and electronic factors and bonding interactions in the lattice, which has never been realized. Therefore, the study presented here can be taken as a general guideline to correlate the reactivity to the structure of the inorganic materials.
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Affiliation(s)
- Anubha Rajput
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, 110016 New Delhi, India
| | - Pabitra Kumar Nayak
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, 110016 New Delhi, India
| | - Dibyajyoti Ghosh
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, 110016 New Delhi, India
- Department of Materials Science and Engineering, Indian Institute of Technology Delhi, Hauz Khas, 110016 New Delhi, India
| | - Biswarup Chakraborty
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, 110016 New Delhi, India
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Dağlıoğlu Y, Öztürk BY, Khatami M. Apoptotic, cytotoxic, antioxidant, and antibacterial activities of biosynthesized silver nanoparticles from nettle leaf. Microsc Res Tech 2023; 86:669-685. [PMID: 36883432 DOI: 10.1002/jemt.24306] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 11/23/2022] [Accepted: 02/03/2023] [Indexed: 03/09/2023]
Abstract
Here, we reported the biosynthesis of silver nanoparticles (AgNPs) using Urtica dioica (nettle) leaf extract as green reducing and capping agents and investigate their anticancer and antibacterial, activity. The Nettle-mediated biosynthesized AgNPs was characterized by UV-Vis a spectrophotometer. Their size, shape and elemental analysis were determined with the using of SEM and TEM. The crystal structure was determined by XRD and the biomolecules responsible for the reduction of Ag+ were determined using FTIR analysis. Nettle-mediated biosynthesis AgNPs indicated strong antibacterial activity against pathogenic microorganisms. Again, the antioxidant activity of AgNPs is quite high when compared to ascorbic acid. Anticancer effect of AgNPs, IC50 dose was determined by XTT analysis using MCF-7 cell line and the IC50 value was found to be 0.243 ± 0.014 μg/mL (% w/v).
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Affiliation(s)
- Yeşim Dağlıoğlu
- Molecular Biology and Genetics, Department, Ordu University, Ordu, Turkey
| | - Betül Yılmaz Öztürk
- Central Research Laboratory Application and Research Center, Eskisehir Osmangazi University, Eskisehir, Turkey
| | - Mehrdad Khatami
- Department of Environment of Kerman, The Environmental Researches Center, Kerman, Iran
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Sukanya R, Mohandoss S, Lee YR. Synthesis of active-site rich molybdenum-doped manganese tungstate nanocubes for effective electrochemical sensing of the antiviral drug (COVID-19) nitazoxanide. CHEMOSPHERE 2023; 311:137005. [PMID: 36347350 PMCID: PMC9636157 DOI: 10.1016/j.chemosphere.2022.137005] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/18/2022] [Accepted: 10/23/2022] [Indexed: 06/16/2023]
Abstract
Nitazoxanide (NTZ), a promising antiviral agent, is currently being tested in clinical trials as a potential treatment for novel coronavirus disease 2019 (COVID -19). This paper describes a one-pot hydrothermal synthesis to prepare molybdenum (Mo)-doped manganese tungstate nanocubes (Mo-MnWO4 NCs) for the electrochemical sensing of NTZ. The as-prepared Mo-MnWO4 NCs were characterized using various techniques such as XRD, Raman, FE-SEM, FE-TEM, and XPS to confirm the crystal structure, morphology, and elemental composition. The obtained results demonstrate that Mo doping on MnWO4 generates many vacancy sites, exhibiting remarkable electrochemical activity. The kinetic parameters of the electrode modified with Mo-MnWO4 NCs were calculated to be (Ks) 1.1 × 10-2 cm2 s-1 and (α) 0.97, respectively. Moreover, a novel electrochemical sensor using Mo-MnWO4 NCs was fabricated to detect NTZ, which is used as a primary antibiotic to control COVID-19. Under optimal conditions, the electrochemical reduction of NTZ was determined with a low detection limit of 3.7 nM for a linear range of 0.014-170.2 μM with a high sensitivity of 0.78 μA μM-1 cm-2 and negligible interference with other nitro group-containing drugs, cations, and anions. The electrochemical sensor was successfully used to detect NTZ in the blood serum and urine samples and achieved high recoveries in the range of 94-99.2% and 95.3-99.6%, respectively. This work opens a way to develop high-performance sensing materials by exploring the introduction of defect engineering on metal tungstates to detect drug molecules for practical applications.
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Affiliation(s)
- Ramaraj Sukanya
- School of Chemical Engineering, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, Republic of Korea
| | - Sonaimuthu Mohandoss
- School of Chemical Engineering, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, Republic of Korea
| | - Yong Rok Lee
- School of Chemical Engineering, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, Republic of Korea.
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Hurley N, Srinivas S, Fang J, Sun M, Hong S, Chien CT, Guo A, Khan TA, Li M, Cotlet M, Moretti F, Bourret E, Radin D, Tsirka SE, Shelly M, Wong SS. Investigation of the photoluminescent properties, scintillation behaviour and toxicological profile of various magnesium tungstate nanoscale motifs. ROYAL SOCIETY OPEN SCIENCE 2022; 9:220994. [PMID: 36483754 PMCID: PMC9727672 DOI: 10.1098/rsos.220994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 10/14/2022] [Indexed: 06/17/2023]
Abstract
We have synthesized several morphologies and crystal structures of MgWO4 using a one-pot hydrothermal method, producing not only monoclinic stars and large nanoparticles but also triclinic wool balls and sub-10 nm nanoparticles. Herein we describe the importance of reaction parameters in demonstrating morphology control of as-prepared MgWO4. Moreover, we correlate structure and composition with the resulting photoluminescence and radioluminescence properties. Specifically, triclinic-phase samples yielded a photoluminescence emission of 421 nm, whereas monoclinic-phase materials gave rise to an emission maximum of 515 nm. The corresponding radioluminescence data were characterized by a broad emission peak, located at 500 nm for all samples. Annealing the wool balls and sub-10 nm particles to transform the crystal structure from a triclinic to a monoclinic phase yielded a radioluminescence (RL) emission signal that was two orders of magnitude greater than that of their unannealed counterparts. Finally, to confirm the practical utility of these materials for biomedical applications, a series of sub-10 nm particles, including as-prepared and annealed samples, were functionalized with biocompatible PEG molecules, and subsequently were found to be readily taken up by various cell lines as well as primary cultured hippocampal neurons with low levels of toxicity, thereby highlighting for the first time the potential of this particular class of metal oxides as viable and readily generated platforms for a range of biomedical applications.
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Affiliation(s)
- Nathaniel Hurley
- Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY 11794-3400, USA
| | - Sailesh Srinivas
- Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY 11794-3400, USA
| | - Justin Fang
- Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY 11794-3400, USA
- Department of Neurobiology, State University of New York at Stony Brook, Stony Brook, NY 11794-5230, USA
| | - Manli Sun
- Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY 11794-3400, USA
| | - Simon Hong
- Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY 11794-3400, USA
| | - Chia Te Chien
- Department of Neurobiology, State University of New York at Stony Brook, Stony Brook, NY 11794-5230, USA
| | - Alan Guo
- Department of Neurobiology, State University of New York at Stony Brook, Stony Brook, NY 11794-5230, USA
| | - Tamor A. Khan
- Department of Neurobiology, State University of New York at Stony Brook, Stony Brook, NY 11794-5230, USA
| | - Mingxing Li
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Building 735, Upton, NY 11973, USA
| | - Mircea Cotlet
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Building 735, Upton, NY 11973, USA
| | - Federico Moretti
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Edith Bourret
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Daniel Radin
- Department of Pharmacological Sciences, State University of New York at Stony Brook, Stony Brook, NY 11794-8651, USA
| | - Stella E. Tsirka
- Department of Pharmacological Sciences, State University of New York at Stony Brook, Stony Brook, NY 11794-8651, USA
| | - Maya Shelly
- Department of Neurobiology, State University of New York at Stony Brook, Stony Brook, NY 11794-5230, USA
| | - Stanislaus S. Wong
- Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY 11794-3400, USA
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Saji VS. Nanotubes-nanosheets (1D/2D) heterostructured bifunctional electrocatalysts for overall water splitting. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.141095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Electro-Oxidation of Metal Oxide-Fabricated Graphitic Carbon Nitride for Hydrogen Production via Water Splitting. COATINGS 2022. [DOI: 10.3390/coatings12050548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hydrogen is a great sourcez of energy due to having zero emission of carbon-based contents. It is found primarily in water, which is abundant and renewable. For electrochemical splitting of water molecules, it is necessary to use catalytic materials that minimize energy consumption. As a famous carbon material, graphitic carbon nitride, with its excellent physicochemical properties and diversified functionalities, presents great potential in electrocatalytic sensing. In the present work, graphitic carbon nitride-fabricated metal tungstate nanocomposites are synthesized by the hydrothermal method to study their applications in catalysis, electrochemical sensing, and water splitting for hydrogen production. Nanocomposites using different metals, such as cobalt, manganese, strontium, tin, and nickel, were used as a precursor are synthesized via the hydrothermal process. The synthesized materials (g-C3N4/NiWO4, g-C3N4/MnWO4, g-C3N4/CoWO4, g-C3N4/SnWO4, g-C3N4/SrWO4) were characterized using different techniques, such as FTIR and XRD. The presence of a functional groups between the metal and tungstate groups was confirmed by the FTIR spectra. All the nanocomposites show a tungstate peak at 600 cm−1, while the vibrational absorption bands for metals appear in the range of 400–600 cm−1. X-ray diffraction (XRD) shows that the characteristic peaks matched with the JCPDS in the literature, which confirmed the successful formation of all nanocomposites. The electrochemical active surface area is calculated by taking cyclic voltammograms of the potassium–ferrocyanide redox couple. Among the entire series of metal tungstate, the g-C3N4/NiWO4 has a large surface area owing to the high conductive properties towards water oxidation. In order to study the electrocatalytic activity of the as-synthesized materials, electrochemical water splitting is performed by cyclic voltammetry in alkaline medium. All the synthesized materials proved to be efficient catalysts with enhanced conductive properties towards water oxidation. Among the entire series, g-C3N4-NiWO4 is a very efficient electrocatalyst owing to its higher active surface area and conductive activity. The order of electrocatalytic sensing of the different composites is: g-C3N4-NiWO4 > g-C3N4-SrWO4 > g-C3N4-CoWO4 > g-C3N4-SnWO4 > g-C3N4-MnWO4. Studies on electrochemically synthesized electrocatalysts revealed their catalytic activity, indicating their potential as electrode materials for direct hydrogen evolution for power generation.
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Lima AEB, Assis M, Resende ALS, Santos HLS, Mascaro LH, Longo E, Santos RS, Cavalcante LS, Luz GE. CuWO4|MnWO4 heterojunction thin film with improved photoelectrochemical and photocatalytic properties using simulated solar irradiation. J Solid State Electrochem 2022. [DOI: 10.1007/s10008-022-05143-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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8
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Kerkar RD, Salker AV. Highly active nano-composite of cobalt–copper–manganese oxides for room temperature CO oxidation. APPLIED NANOSCIENCE 2021. [DOI: 10.1007/s13204-021-02232-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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9
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Akbayrak M, Önal AM. Metal oxides supported cobalt nanoparticles: Active electrocatalysts for oxygen evolution reaction. Electrochim Acta 2021. [DOI: 10.1016/j.electacta.2021.139053] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Wu K, Fu P, Ruan B, Wu M, Wu M, Wu R. Performances of MnWO 4@AC mixed oxide composite materials as Pt-free counter electrodes for high efficiently dye sensitized solar cells. NEW J CHEM 2021. [DOI: 10.1039/d0nj05541g] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Replacing the expensive Pt catalyst of counter electrodes (CEs) with a low-cost Pt-free catalyst has been regarded as one of the crucial steps for cost effectiveness of dye-sensitized solar cells (DSSCs).
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Affiliation(s)
- Kezhong Wu
- Key Laboratory of Inorganic Nano-materials of Hebei Province
- Department of Chemistry and Material Science
- Hebei Normal University
- Shijiazhuang
- P. R. China
| | - Pengyuan Fu
- Key Laboratory of Inorganic Nano-materials of Hebei Province
- Department of Chemistry and Material Science
- Hebei Normal University
- Shijiazhuang
- P. R. China
| | - Bei Ruan
- Key Laboratory of Inorganic Nano-materials of Hebei Province
- Department of Chemistry and Material Science
- Hebei Normal University
- Shijiazhuang
- P. R. China
| | - Mengmeng Wu
- Key Laboratory of Inorganic Nano-materials of Hebei Province
- Department of Chemistry and Material Science
- Hebei Normal University
- Shijiazhuang
- P. R. China
| | - Mingxing Wu
- Key Laboratory of Inorganic Nano-materials of Hebei Province
- Department of Chemistry and Material Science
- Hebei Normal University
- Shijiazhuang
- P. R. China
| | - Ruitao Wu
- Key Laboratory of Inorganic Nano-materials of Hebei Province
- Department of Chemistry and Material Science
- Hebei Normal University
- Shijiazhuang
- P. R. China
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11
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Xu W, Dong X, Wang Y, Zheng N, Zheng B, Lin Q, Zhao Y. Controllable Synthesis of MoS
2
/Carbon Nanotube Hybrids with Enlarged Interlayer Spacings for Efficient Electrocatalytic Hydrogen Evolution. ChemistrySelect 2020. [DOI: 10.1002/slct.202003827] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Wenwen Xu
- School of Light Industry and Chemical Engineering Dalian Polytechnic University #1 Qinggongyuan Dalian 116034 P. R. China
| | - Xiaoli Dong
- School of Light Industry and Chemical Engineering Dalian Polytechnic University #1 Qinggongyuan Dalian 116034 P. R. China
| | - Yu Wang
- School of Light Industry and Chemical Engineering Dalian Polytechnic University #1 Qinggongyuan Dalian 116034 P. R. China
| | - Nan Zheng
- School of Light Industry and Chemical Engineering Dalian Polytechnic University #1 Qinggongyuan Dalian 116034 P. R. China
| | - Bingrong Zheng
- School of Light Industry and Chemical Engineering Dalian Polytechnic University #1 Qinggongyuan Dalian 116034 P. R. China
| | - Qing Lin
- School of Light Industry and Chemical Engineering Dalian Polytechnic University #1 Qinggongyuan Dalian 116034 P. R. China
| | - Yilin Zhao
- School of Light Industry and Chemical Engineering Dalian Polytechnic University #1 Qinggongyuan Dalian 116034 P. R. China
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12
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Rani BJ, Ravi G, Yuvakkumar R, Velauthapillai D, Saravanakumar B, Al-Mohaimeed AM. Investigation on copper based oxide, sulfide and selenide derivatives oxygen evolution reaction activity. APPLIED NANOSCIENCE 2020. [DOI: 10.1007/s13204-020-01531-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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13
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Jansi Rani B, Ravi G, Yuvakkumar R, Praveenkumar M, Ravichandran S, Muthu Mareeswaran P, Hong SI. Bi 2WO 6 and FeWO 4 Nanocatalysts for the Electrochemical Water Oxidation Process. ACS OMEGA 2019; 4:5241-5253. [PMID: 31459696 PMCID: PMC6648914 DOI: 10.1021/acsomega.8b03003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 03/05/2019] [Indexed: 06/10/2023]
Abstract
Polyvinylpyrrolidone (PVP)-assisted nanocatalyst preparation was succeeded by employing a controlled solvothermal route to produce efficient electrodes for electrochemical water-splitting applications. Bi2WO6 and FeWO4 nanocatalysts have been confirmed through the strong signature of (113) and (111) crystal planes, respectively. The binding natures of Bi-W-O and Fe-W-O have been thoroughly discussed by employing X-ray photoelectron spectroscopy which confirmed the formation of Bi2WO6 and FeWO4. The freestanding nanoplate array morphology of Bi2WO6 and the fine nanosphere particle morphology of FeWO4 nanocatalysts were revealed by scanning electron microscopy images. With these confirmations, the fabrication of durable, long-term electrodes for electrochemical water splitting has been subjected to efficient oxidation of water, confirmed by obtaining 2.79 and 1.96 mA/g for 0.5 g PVP-assisted Bi2WO6 and FeWO4 nanocatalysts, respectively. The water oxidation mechanism of both nanocatalysts has been revealed with the support of 24 h stability test over continuous water oxidation and faster charge transfer achieved by the smaller Tafel slope values of 75 and 78 mV/dec, respectively. Generally, these nanocatalysts are utilized for photocatalytic applications. The present study revealed the PVP-assisted synthesis to produce electrocatalytically active nanocatalysts and their electrochemical water-splitting mechanism which will offer a pathway for research interests with regard to the production of multifunctional nanocatalysts for both electro- and photocatalytic applications in the near future.
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Affiliation(s)
- Balasubramanian Jansi Rani
- Nanomaterials
Laboratory, Department of Physics, and Department of Industrial Chemistry, Alagappa University, Karaikudi 630003, Tamil Nadu, India
| | - Ganesan Ravi
- Nanomaterials
Laboratory, Department of Physics, and Department of Industrial Chemistry, Alagappa University, Karaikudi 630003, Tamil Nadu, India
| | - Rathinam Yuvakkumar
- Nanomaterials
Laboratory, Department of Physics, and Department of Industrial Chemistry, Alagappa University, Karaikudi 630003, Tamil Nadu, India
| | - M. Praveenkumar
- Electro
Inorganic Division, CSIR-Central Electrochemical
Research Institute (CSIR-CECRI), Karaikudi 630003, Tamil Nadu, India
| | - Subbiah Ravichandran
- Electro
Inorganic Division, CSIR-Central Electrochemical
Research Institute (CSIR-CECRI), Karaikudi 630003, Tamil Nadu, India
| | - Paulpandian Muthu Mareeswaran
- Nanomaterials
Laboratory, Department of Physics, and Department of Industrial Chemistry, Alagappa University, Karaikudi 630003, Tamil Nadu, India
| | - Sun Ig Hong
- Department
of Nanomaterials Engineering, Chungnam National
University, Daejeon 305-764, South Korea
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