Doping Modification Research Articles

Promoting the performances of NaTi2(PO4)3 electrode for sodium ion battery by reasonable crystal design and surface modification

Sodium-ion battery as an attractive energy storage system is acknowledged as alternative to lithium-ion battery on account of their extensive resources and low price. NaTi2(PO4)3 is considered as an excellent electrode material in sodium-ion battery due to open three-dimensional crystal channels for ion diffusion. In this work, reasonable crystal design of Zr doping and surface modification of carbon coating strategy was employed to promote the sodium storage performances of NaTi2(PO4)3 electrode. A series of NaTi2-xZrx(PO4)3/C (x = 0.05, 0.1, 0.15) composites with core@shell structure were synthesized through an easy sol-gel route, and were applied as electrode for sodium ion battery. The result shows that the crystal type of all samples is relatively pure. However, the dispersion of Zr doped samples are significantly improved compared to the blank sample. Among all the samples, NTP-Zr-0.1 (NaTi1.9Zr0.1(PO4)3/C) demonstrates the best charge/discharge performances. It delivers the discharge capacities of 206.3 mA h g-1 at 40 mA g-1 and 79.2 mA h g-1 at 2000 mA g-1, while those of NTP are 116.2 and 26.9 mA h g-1, severally. Superior electrochemical performance of NTP-Zr-0.1 is probably ascribed to the carbon coating structure, good dispersion, and lattice volume increase, further accelerating the transfer of electron and sodium ion. This study implies that carbon coating and Zr doping are facile and efficient strategy for promoting performances of NaTi2(PO4)3/C composite.

Enhanced dielectric and piezoelectric performance of (1-x)Bi0.5(Na0.78K0.22)0.5TiO3-xBaTiO3 ceramics

High-performance (1-x)Bi0.5(Na0.78K0.22)0.5TiO3-xBaTiO3 lead free ceramics were synthesized by traditional solid-state technology. Combined with K+ doping and BaTiO3 solid solution modification, morphotropic phase boundary was constructed and the electrical performance of NBT-based ceramics were significantly improved. The sample (x = 0.06) has maximum dielectric constant of 2054, minimum dielectric loss of 0.034, piezoelectric constant increased from 140pC/N to 184pC/N, and planar electromechanical coupling coefficient increased from 30% to 49%. The modified samples improve the depolarization temperature and the stability of piezoelectric constant at high temperature. The obtained electrical parameters are compared with the results in other references. Lattice theory and domain theory were used to explain the origin of excellent piezoelectric performance.

Investigating the Redox Properties of Two-Dimensional MoS2 Using Photoluminescence Spectroelectrochemistry and Scanning Electrochemical Cell Microscopy.

Control over photophysical and chemical properties of two-dimensional (2D) transition metal dichalcogenides (TMDs) is the key to advance their applications in next-generation optoelectronics. Although chemical doping and surface modification with plasmonic metals have been reported to tune the photophysical and catalytic properties of 2D TMDs, there have been few reports of tuning optical properties using dynamic electrochemical control of electrode potential. Herein, we report (1) the photoluminescence (PL) enhancement and red-shift in the PL spectrum of 2D MoS2, synthesized by chemical vapor deposition and subsequent transfer onto an indium tin oxide electrode, upon electrochemical anodization and (2) spatial heterogeneities in its photoelectrochemical (PEC) activities. Spectroelectrochemistry shows that positive electrochemical bias causes an initial ten-fold increase in the PL intensity followed by a quick decrease in the enhancement. The PL enhancement and spectrum red-shift are associated with the decrease in nonradiative decay rates of excitons formed upon electrochemical anodization of 2D MoS2. Additionally, scanning electrochemical cell microscopy (SECCM) study shows that the 2D MoS2 crystal is spatially sensitive to PEC oxidation at positive potentials. SECCM also shows a photocurrent increase caused by spatially heterogeneous edge-type defect sites of the crystal.

Nb5+ doped Li1.20Mn0.54Ni0.13Co0.13O2 with Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) surface modification as advanced cathode material for Li-ion batteries

Abstract The conductive polymers PEDOT:PSS coated Li1.20[Mn0.53Ni0.13Co0.13Nb0.01]O2 cathode materials were synthesized via using the sol-gel method, followed by the wet solution process. And the X-ray diffraction (XRD), Rietveld refinement, Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) were adopted to investigate the morphology and constituents of as-prepared cathode materials. The results demonstrated that a PEDOT:PSS layer was uniformly distributed on the surface of bulk Li1.20Mn0.54Ni0.13Co0.13O2 with Nb5+ doping successfully. And the PEDOT:PSS surface coating and Nb5+ doping modifications showed a significant improvement on the electrochemical properties of cathode. In particular, the 2 wt% PEDOT:PSS coated Li1.20[Mn0.53Ni0.13Co0.13Nb0.01]O2 delivered a supernal discharge capacity of 145.6 mAhg−1 at 5C high rate and retained a high capacity retention of 90.8% after 200 cycles at 45 °C, which were more superior than those of the pristine cathode (90.2 mAhg−1 and 80.7%). The enhanced electrochemical properties could be attributed to the facilitation of Lithium ions diffusion, the lower cation mixing and restriction of the side reactions between cathode surfaces with electrolyte by the Nb5+ doping and PEDOT:PSS coating.

Tunable phase transition in (Bi0.5Na0.5)0.94Ba0.06TiO3 by B-site cations

The role of B-site ions of Bi0.5Na0.5TiO3 (BNT) on its complex phase transition remains unclear due to its polarization attributing to both Bi and Ti. In this paper, the phase transition of (Bi0.5Na0.5)0.94Ba0.06(Ti1−0.01b/4B0.01)O3 (BNT6BT) (B = Nb, Mn, Fe, and Cu) ceramics was modified by low-concentration donor doping (Nb) and acceptor doping (Mn, Fe, and Cu) in order to determine the origin of phase transition behavior. The phase structure, microstructure, local structure/lattice vibration, phase transition temperature, and dielectric properties of BNT6BT-Nb, Mn, Fe, and Cu ceramics were investigated. Results showed that all samples formed a single perovskite phase at room temperature, and donor (Nb) and acceptor (Mn, Fe, and Cu) doping can regulate the ratio of R3c and P4bm coexisting as nanoscale entities. The grains show polyhedral morphology, and average grain size lies between 1 and 2 μm. The Raman spectroscopy study shows that doping modification can change the phase transition temperature. The relation is in well agreement with the three different dielectric anomalies derived from the dielectric curves of er versus T. Low concentration of cation (Nb, Mn, Fe, and Cu) doping can tailor the dielectric permittivity, depolarization temperature, and phase transition temperature of BNT6BT. All samples exhibit a large dielectric constant and good frequency stability.

Fabricating Surface-Functionalized CsPbBr3/Cs4PbBr6 Nanosheets for Visible-Light Photocatalytic Oxidation of Styrene.

The halide perovskite (PVSK) material, an excellent light absorber with fast carrier kinetics, has received increased attention as a potential photocatalyst for organic synthesis. Herein, we report a straightforward synthesis of chemically modified halide perovskite and its application as an efficient photocatalyst to convert styrene into benzaldehyde. A simple method is employed to synthesize the chemically modified CsPbBr3/Cs4PbBr6 nanosheets by using ZrCl4 to simultaneously achieve the Cl doping and the surface modification with Zr species. The photocatalytic oxidation rate of styrene to benzaldehyde catalyzed by surface-modified CsPbBr3/Cs4PbBr6 nanosheets under visible light can reach 1,098 μmol g−1 h−1, 2.9 times higher than that of pristine CsPbBr3/Cs4PbBr6 nanosheets (372 μmol g−1 h−1). The enhanced photocatalytic performance may originate from the modified band structure induced by the synergistic effect of Cl doping and surface modification, whereby the same methodology can be applied to MAPbBr3. This work demonstrates the surface modification of PVSK materials and their potential as efficient photocatalyst toward organic synthesis.

Transparent Zirconium-doped Hematite Nanocoral Photoanode via In-Situ Diluted Hydrothermal Approach for Efficient Solar Water Splitting

To tackle the problem of bulk recombination and to solve the holes diffusion issue in hematite, the shape-guiding and in situ doping is an effective strategy. Herein, we developed a novel strategy for designing and fabricating zirconium-doped transparent hematite (Zr-Fe2O3(I)) photoanode through an in situ hydrothermal method and stoichiometric iron and zirconium dilution. The concentration of ZrO(NO3)2 and FeCl3·6H2O in the precursor solution effectively influenced the transparency and morphology of zirconium-doped Fe2O3. The XPS and TEM analyses confirms the co-existence of Zr doping and surface modification of Fe2O3 nanocoral diffused ZrO2 after high temperature quenching. Synergism between the Zr doping and ZrO2 layer facilizes the charge transfer in Zr-Fe2O3 nanocoral (NC) photoanodes. Among the photoanodes prepared by variously diluted concentrations of the iron and zirconium precursor, the in situ 1/32 Zr-Fe2O3 nanocoral (NC) photoanode achieved an excellent photocurrent density of 1.55 mA cm2 at 1.23 V vs. RHE, which is about doubles than that of the conventional pristine Fe2O3 (P-Fe2O3) NR. Additionally, as result of in situ Zr doping, favorable nanocoral morphology and ZrO2 surface modification exhibits the decreased changer transfer resistance and increased incident photon to current efficiency (IPCE) of 1/32 Zr-Fe2O3 NC upto 21.9%. This in situ Zr-doping and nanocoral morphology 1/32 Zr-Fe2O3 fulfills the requirements of both high charge separation efficiency and improved water oxidation kinetics. A novel 1/32 Zr-Fe2O3 (I) NC photoanode exhibits O2 and H2 evolution up to 69 and 138 μmol during 5 h of overall pure water splitting. This novel in situ hydrothermal dilution approach is feasible for fabricating a transparent hematite photoanode with NC morphology for practical PEC water splitting.

Synthesis of transparent Zr-doped ZnFe2O4 nanocorals photoanode and its surface modification via Al2O3/Co–Pi for efficient solar water splitting

The Zr-doped ZnFe2O4 (Zr-ZFO) nanocorals photoanode have been synthesized from Zr-doped FeOOH (Zr–FeOOH) nanocorals on fluorine-doped tin oxide (FTO) substrate followed by Al2O3/Co–Pi surface modification for effective PEC water splitting. The hydrothermal method was adopted for the synthesis of in situ Zr doping in FeOOH, while Zr-ZFO nanocorals was fashioned by subsequent additional procedures, such as Zn(NO3)2 precursor dropping, first quenching, etching and second quenching. The Al2O3 layer decreases the over-potential of the Zr-ZFO photoanode‖electrolyte interface as well as lowers the charge transfer resistance which aids to increase in the photocurrent density from 0.24 mA/cm2 to 0.36 mA/cm2 at 1.23 V vs. RHE under 1 sun illumination condition. The subsequent loading of cobalt phosphate (Co–Pi) as a co-catalyst leads to an improved photocurrent density of 0.49 mA/cm2 at 1.23 V vs. RHE. These synergistic effects of Zr doping and surface modification led to remarkable improvement in photocurrent density from 0.19 mA/cm2 (at 1.4 V vs. RHE) for conventional ZFO nanorods to 0.65 mA/cm2 for the Zr-ZFO/Al2O3/CoPi photoanode. A systematic investigation into the effect of Zr doping and Al2O3/Co–Pi overlayer reveals the reduction of two distinct recombination processes (bulk and surface) in ZFO photoanode.

Mg2+ Doped LiNi1/3Co1/3Mn1/3O2 Hollow Flake–Like Structures with Enhanced Performances Cathodes for Lithium–Ion Batteries

AbstractLiNi1/3Co1/3Mn1/3O2 ternary cathode is a dominant cathode material for lithium ion batteries due to its relatively stable structure. However, LiNi1/3Co1/3Mn1/3O2 still suffers from the poor rate capability and high cation disorder problems. Herein, the Mg–doped Li(Ni1/3Co1/3Mn1/3)0.99Mg0.01O2 cathode materials with hollow flake–like hierarchical fiber structures are successfully synthesized by a facile wet spinning method and the pressing pretreatment of precursor powders on the electrochemical performance is also systematically investigated. The diameter of the pre−synthesized hollow laminar nano−fibers are about 20 μm and approximately 50 nm in thickness with homogeneous primary nanoparticles (∼50 nm). Benefitting from the pillaring effects of inert Mg in the crystal structure and hollow laminar structure, the Li(Ni1/3Co1/3Mn1/3)0.99Mg0.01O2 cathodes deliver significantly improved electrochemical performance, achieving high stability discharge specific capacity 178.8 mA h g−1 with capacity retention of 88 % at 0.5 C (137.5 mA g−1) rate after 200 cycles. Moreover, it maintains a high rate capacity of 110 mA h g−1 even at a current density of 5 C. Based on this work, the conception of combining microstructure design and doping modification can facilitate the development of higher−performance Li−ion battery cathode materials.

Metal-Free Modified Boron Nitride for Enhanced CO2 Capture

Porous boron nitride is a new class of solid adsorbent with applications in CO2 capture. In order to further enhance the adsorption capacities of materials, new strategies such as porosity tuning, element doping and surface modification have been taken into account. In this work, metal-free modification of porous boron nitride (BN) has been prepared by a structure directing agent via simple heat treatment under N2 flow. We have demonstrated that textural properties of BN play a pivotal role in CO2 adsorption behavior. Therefore, addition of a triblock copolymer surfactant (P123) has been adopted to improve the pore ordering and textural properties of porous BN and its influence on the morphological and structural properties of pristine BN has been characterized. The obtained BN-P123 exhibits a high surface area of 476 m2/g, a large pore volume of 0.83 cm3/g with an abundance of micropores. More importantly, after modification with P123 copolymer, the capacity of pure CO2 on porous BN has improved by about 34.5% compared to pristine BN (2.69 mmol/g for BN-P123 vs. 2.00 mmol/g for pristine BN under ambient condition). The unique characteristics of boron nitride opens up new routes for designing porous BN, which could be employed for optimizing CO2 adsorption.

Photocatalytic activity enhancement of Bi2WO6 nanoparticles by Ag doping and Ag nanoparticles modification

Bi2WO6 nanoparticles doped with Ag, and modified with Ag nanoparticles, were successfully prepared using a two-step microwave assisted and hydrothermal synthesis. With Ag doping, the Bi ions were substituted by the dopant Ag ions in the host lattice structure of Bi2WO6. With Ag nanoparticles modification, the Ag nanoparticles grew on the surface of the Bi2WO6 nanoparticles without changing the host lattice structure. The photocatalytic activities of the samples were studied by visible light irradiation of rhodamine B. Both the Ag doping and the Ag nanoparticles modification enhanced the photocatalytic activity of the Bi2WO6 nanoparticles. Moreover, Ag nanoparticles modification produced a more than two times higher enhancement of the photocatalytic activity than the Ag doping method. Furthermore, a mechanism of the significant photocatalytic activity enhancement by Ag nanoparticles modification is proposed.

Pyrolytic Carbon Films with Tunable Electronic Structure and Surface Functionality: A Planar Stand‐In for Electroanalysis of Energy‐Relevant Reactions

AbstractFundamental charge‐transfer dynamics for technologically relevant carbons, such as disordered “hard” carbons, can be studied by designing planar mimics. We fabricate thin films of “pyrolytic carbon” (pyC) by decomposition of benzene at 1000 °C and examine the physical and electrochemical properties of the native pyC film, as well as variants after heteroatom doping, plasma oxidation, and metal nanoparticle modification. The pyC films are optically reflective at the macroscale, relatively planar (1–3 nm RMS roughness by atomic force microscopy) and disordered (via Raman scattering). Thiophenyl‐doped pyC films (0.6–1.7 atom % sulfur) suitably mimic the disorder, chemical state (X‐ray photoelectron spectroscopy), and work function (Kelvin probe) of a workhorse carbon black, Vulcan XC‐72. Using ferri/ferrocyanide as a redox probe, we find that oxygen functionalities enhance the heterogeneous electron‐transfer rate constant up to 3×, while high levels of sulfur dopants decrease the rate 2×. We also explore thiophenyl‐directed adsorption of Au nanoparticles and show that hydrogen evolution at 0.1 mA cm−2 occurs ∼95 mV more positive at <1 % Au@pyC∼S than at pyC∼S.

Preparation and photoelectric properties of praseodymium-doped cuprous oxide thin films

Pr-doped Cu2O films were deposited on Cu sheet substrates by hydrothermal method with different doping concentrations of Pr(NO3)3. The result shows that undoped and Pr-doped Cu2O thin films are all p-type semiconductors. Compared with undoped Cu2O, the photovoltage, photocurrent density, and carrier concentration of Pr-doped Cu2O increase to 0.4401 V, 1.1 mA/cm2, and 9.66 × 1019 cm−3, respectively. And the increments are 0.0828 V, 0.52 mA/cm2, and 8.931 × 1019 cm−3, respectively. The increments of the capacitances of Pr doping modification illustrate that Pr element has a strong passivation effect on the composite of electrons and holes, thus improving the photoelectric performance of Cu2O. The preferential growth surface of Pr-doped Cu2O film is (111) and (200), and the crystallinity of (111) plane is optimal. After doping modification, the grain size of Pr-doped Cu2O is increased and the particle size is relatively uniform. The mass percentage of Pr element is 0.46% and the forbidden band width reduces from 2.02 to 1.83 eV. XPS peak fitting of Pr-doped Cu2O indicates that Pr element is doped into Cu2O film.

Role of inorganic nanoparticle degradation in cancer therapy.

Nanomaterials are currently widely exploited for their potential in the development of novel cancer therapies, and so far, mainly nanoparticles (NPs) consisting of liposomes and polymers have made their way into the clinic. However, major bottlenecks for the clinical translation of other types of NPs (i.e. inorganic) are the lack of knowledge concerning their long-term distribution in vivo and their potential toxicity. To counter this, various research groups have worked on soluble NPs, such as zinc oxide (ZnO), copper oxide (CuO), and silver (Ag), which tend to dissolve spontaneously into their ionic form, releasing toxic metal ions and leading to reactive oxygen species (ROS) generation when exposed to cellular environments. By fine-tuning the dissolution kinetics of these NPs, it is possible to control the level of ROS production and thus cytotoxicity to selectively destroy tumor tissue. Specifically, cancer cells tend to exhibit a higher basal level of oxidative stress compared to normal cells due to their higher metabolic rates, and therefore, by engineering NPs that generate sufficient ROS that barely exceed toxic thresholds in cancer cells, normal cells will only experience reversible transient damage. This review focuses on the use of these soluble inorganic NPs for selective cancer therapy and on the various in vitro and in vivo studies that have aimed to control the dissolution kinetics of these NPs, either through particle doping or surface modifications.

A first-principles computational comparison of defect-free and disordered, fluorinated anatase TiO2 (001) interfaces with water.

Chemical doping and other surface modifications have been used to engineer the bulk properties of materials, but their influence on the surface structure and consequently the surface chemistry are often unknown. Previous work has been successful in fluorinating anatase TiO2 with charge balance achieved via the introduction of Ti vacancies rather than the reduction of Ti. Our work here investigates the interface between this fluorinated titanate with cationic vacancies and a monolayer of water via density functional theory based molecular dynamics. We compute the projected density of states for only those atoms at the interface and for those states that fall within 1 eV of the Fermi level for various steps throughout the simulation, and we determine that the variation in this visualization of the density of states serves as a reasonable tool to anticipate where surfaces are most likely to be reactive. In particular, we conclude that water dissociation at the surface is the main mechanism that influences the anatase (001) surface whereas the change in the density of states at the surface of the fluorinated structure is influenced primarily through the adsorption of water molecules.

Research progress of pyroelectric characteristics of lead-free ferroelectric ceramics for infrared detection

Due to the excellent pyroelectric properties, ferroelectric ceramics containing lead element are widely used as sensitive materials in pyroelectric infrared detectors at present. The research and development of lead-free ferroelectric ceramics for this kind of detector has become a hot research spot in the areas of dielectric physics and materials in recent years. In this article, the recent research progress of the pyroelectric effect in series of important lead-free ferroelectric ceramic systems is reviewed, including barium titanate, sodium bismuth titanate, potassium sodium niobite, barium strontium niobite, etc. The methods of enhancing the pyroelectric effect are summarized, including doping modification, phase boundary design, process improvement, etc. Through comparative analysis of the relationship between pyroelectric properties and depolarization temperatures of different systems, it is concluded that bismuth sodium titanate based ceramics are the most potential lead-free materials in the future. The prospective research work of lead-free ferroelectric ceramics for infrared detection is also suggested.

Potassium doping-induced variations in the structures and photoelectric properties of a MAPbI3 perovskite and a MAPbI3/TiO2 junction.

It has been experimentally demonstrated that mixed metallic cation modification could be an effective strategy to enhance the performance and stability of perovskite-based solar cells (PSCs). However, there is limited microscopic understanding at the atomic/molecular level of the behavior of small radius alkali metal cation doping in both perovskite materials and perovskite/TiO2 junctions. Here, we perform a first-principles density functional theory study on the doping-induced variation of the geometric and electronic structures of MAPbI3 (MA = methylammonium) and the MAPbI3/TiO2 junction. The impacts of different doping methods, and different charge states and locations of the given dopants have been investigated. At first, we theoretically confirm that the structures doped by K+ are the most thermally stable compared to the structures doped by the other charge states of K, and that K+ dopants prefer to modify the perovskite lattice interstitially and stay near the MAPbI3/TiO2 interface. Meanwhile, we find that a severe geometric deformation occurs if two doped lattices come into contact directly, indicating that the lattice may rapidly collapse from the interior if the doping concentration is too high. Additionally, we observe that K+ doped interstitially near the MAPbI3/TiO2 interface causes the intensive distortion of the surface Ti-O bonds and severe bond-length fluctuations. Consequently, this results in distorted TiO2 bands of the interfacial layer and a slight decrease of the band offset of conduction bands between two phases. This work complements experiments and provides a better microscopic understanding of the doping modification of the properties of perovskite materials and PSCs.

Tuning the Multifunctional Surface Chemistry of Reduced Graphene Oxide via Combined Elemental Doping and Chemical Modifications.

The synthesis of graphene materials with multiple surface chemistries and functionalities is critical for further improving their properties and broadening their emerging applications. We present a simple chemical approach to obtain bulk quantities of multifunctionalized reduced graphene oxide (rGO) that combines chemical doping and functionalization using the thiol-ene click reaction. Controllable modulation of chemical multifunctionality was achieved by simultaneous nitrogen doping and gradual chemical reduction of graphene oxide (GO) using ammonia and hydrazine, followed by covalent attachment of amino-terminated thiol molecules using the thiol-ene click reaction. A series of N-doped rGO (N-rGO) precursors with different levels of oxygen groups were synthesized by adjusting the amount of reducing agent (hydrazine), followed by subsequent covalent attachment of cysteamine via the thermal thiol-ene click reaction to yield different ratios of mixed functional groups including N (pyrrolic N, graphitic N, and aminic N), S (thioether S, thiophene S, and S oxides), and O (hydroxyl O, carbonyl O, and carboxyl O) on the reduced GO surface. Detailed XPS analysis confirmed the disappearance of unstable pyridinic N in cys-N-rGO and the reduction degree threshold of N-rGO for effective cysteamine modification to take place. Our study establishes a strong correlation between different reduction degrees of N-rGO with several existing oxygen functional groups and addition of new tunable functionalities including covalently attached nitrogen (amino) and sulfur (C–S–C, C=S, and S–O). This simple and versatile approach provides a valuable contribution for practical designing and synthesis of a broad range of functionalized graphene materials with tailorable functionalities, doping levels, and interfacial properties for potential applications such as polymer composites, supercapacitors, electrocatalysis, adsorption, and sensors.

Engineering the Interfacial Electronic Structure of Epitaxial Ge/AlAs(001) Heterointerfaces via Substitutional Boron Incorporation: The Roles of Doping and Interface Stoichiometry

A joint experimental and theoretical framework for the decoupling of boron (B) doping and stoichiometric-induced modifications to the structural properties and electronic band structure of germanium (Ge)/AlAs(001) heterostructures is presented. The effect of B-induced stress on nearest-neighbor Ge bonds is quantified via X-ray diffractometry and Raman spectroscopic analysis and subsequently interpreted through the lens of density functional perturbation theory. Similarly, experimental determination of the energy band alignment at the p-type Ge:B/AlAs heterointerface is understood using a density functional theory approach to model the influence of heterointerface stoichiometry and interatomic bonding between group IV and III–V interfacial atoms on the valence and conduction band discontinuities. The modeled two monolayer interatomic diffusion at the Ge/AlAs heterointerface is confirmed via atom probe tomography analysis, demonstrating a ∼6 A interfacial width. These results present a unified picture of th...

Activating ZnWO4 nanorods for efficient electroanalysis of bisphenol A via the strategy of In doping induced band gap change

The design and development of an ideal method for treating and monitoring endocrine disruptors have become one of the greatest challenges for solving the problems of environment and human health. In this study, different proportions of In were doped into ZnWO4 nanorods by hydrothermal methods. The effect of the doped In element on its structure, morphology, electrocatalytic performance was systematically studied. Modified carbon paste electrode by different ratios of In-doped ZnWO4 nanorods a simple, rapid and sensitive electrochemistry sensor for bisphenol A(BPA) was developed. The results show that the catalytic efficiency of In-doped ZnWO4 nanorods for BPA was 3.6 times higher than that of pure ZnWO4. The proposed sensor produced a wide linear range of 0.01–20 μM and a low detection limit (3.4 nM, S/N = 3) by differential pulse voltammograms measurements. Satisfactory repeatability, stability and anti-interference performance are also achieved on In-doped ZnWO4/CPE. Meanwhile, the proposed sensor realizes the detection of BPA spiked in local tap water samples successfully. Moreover, the possible mechanism of In-doped ZnWO4 nanorods for BPA catalysis and the feasibility of ZnWO4 doping modification were clarified, which provides a novel and effective strategy for the design and synthesis of high performance electrocatalysts.