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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

Synthesis of nickel oxide nanospheres by a facile spray drying method and their application as anode materials for lithium ion batteries

Graphical abstract: NiO nanospheres prepared by a facile spray drying method show high lithium ion storage performance as anode of lithium ion battery. - Highlights: • NiO nanospheres are prepared by a spray drying method. • NiO nanospheres are composed of interconnected nanoparticles. • NiO nanospheres show good lithium ion storage properties. - Abstract: Fabrication of advanced anode materials is indispensable for construction of high-performance lithium ion batteries. In this work, nickel oxide (NiO) nanospheres are fabricated by a facial one-step spray drying method. The as-prepared NiO nanospheres show diameters ranging from 100 to 600 nm and are composed of nanoparticles of 30–50 nm. As an anode for lithium ion batteries, the electrochemical properties of the NiO nanospheres are investigated by cyclic voltammetry (CV) and galvanostatic charge/discharge tests. The specific reversible capacity of NiO nanospheres is 656 mA h g{sup −1} at 0.1 C, and 476 mA h g{sup −1} at 1 C. The improvement of electrochemical properties is attributed to nanosphere structure with large surface area and short ion/electron transfer path.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2015

Noncovalently-functionalized reduced graphene oxide sheets by water-soluble methyl green for supercapacitor application

Graphical abstract: Electroactive methyl green (MG) is selected to functionalize reduced graphene oxide (RGO) through non-covalent modification and the composite achieves high specific capacitance, good rate capability and excellent long life cycle. - Highlights: • MG–RGO composites were firstly prepared through non-covalent modification. • The mass ratio in composites is a key for achieving high specific capacitance. • MG–RGO 5:4 exhibits the highest specific capacitance of 341 F g{sup −1}. • MG–RGO 5:4 shows excellent rate capability and long life cycle. - Abstract: In the present work, water-soluble electroactive methyl green (MG) has been used to non-covalently functionalize reduced graphene oxide (RGO) for enhancing supercapacitive performance. The microstructure, composition and morphology of MG–RGO composites are systematically characterized by UV–vis absorption, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The electrochemical performances are investigated by cyclic voltammetry (CV), galvanostatic charge/discharge and electrochemical impedance spectroscopy (EIS). The fast redox reactions from MG could generate additional pseudocapacitance, which endows RGO higher capacitances. As a result, the MG–RGO composite (with the 5:4 mass ratio of MG:RGO) achieve a maximum value of 341 F g{sup −1} at 1 A g{sup −1} within the potential range from −0.25 to 0.75 V and provide a 180% enhancement in specific capacitance in comparison with pure RGO. Furthermore, excellent rate capability (72% capacitance retention from 1 A g{sup −1} to 20 A g{sup −1}) and long life cycle (12% capacitance decay after 5000 cycles) are achieved for the MG–RGO composite electrode.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2015

Amperometric sensing of hydrogen peroxide using glassy carbon electrode modified with copper nanoparticles

In this paper, fabrication of glassy carbon electrode (GCE) modified with nano copper particles is discussed. The modified electrode has been tested for the non-enzymatic electrochemical detection of hydrogen peroxide (H{sub 2}O{sub 2}). The copper nanoparticles (Cu NPs) were prepared employing a simple chemical reduction method. The presence of Cu NPs was confirmed through UV–visible (UV–vis) absorption spectroscopy and X-ray diffraction (XRD) analysis. The size and morphology of the particles were investigated using transmission electron microscopy (TEM). The electrochemical properties of the fabricated sensor were studied via cyclic voltammetry (CV), chronoamperometry and electrochemical impedance spectroscopy (EIS). The electrochemical sensor displayed excellent performance features towards H{sub 2}O{sub 2} detection exhibiting wide linear range, low detection limit, swift response time, good reproducibility and stability.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2015

Nanotubes within transition metal silicate hollow spheres: Facile preparation and superior lithium storage performances

Highlights: • The hollow Co{sub 2}SiO{sub 4}, MnSiO{sub 3} and CuSiO{sub 3} were successfully prepared by a facile hydrothermal method using SiO{sub 2} nanosphere. • The hollow Co{sub 2}SiO{sub 4}, MnSiO{sub 3} and CuSiO{sub 3} were tested as anode materials for lithium batteries. • The hollow Co{sub 2}SiO{sub 4}, MnSiO{sub 3} and CuSiO{sub 3} delivered superior electrochemical performance. • The lithium storage mechanism is probe via cyclic voltammetry and XPS. - Abstract: A series of transition metal silicate hollow spheres, including cobalt silicate (Co{sub 2}SiO{sub 4}), manganese silicate (MnSiO{sub 3}) and copper silicate (CuSiO{sub 3}.2H{sub 2}O, CuSiO{sub 3} as abbreviation in the text) were prepared via a simple and economic hydrothermal method by using silica spheres as chemical template. Time-dependent experiments confirmed that the resultants formed a novel type of hierarchical structure, hollow spheres assembled by numerous one-dimensional (1D) nanotubes building blocks. For the first time, the transition metal silicate hollow spheres were characterized as novel anode materials of Li-ion battery, which presented superior lithium storage capacities, cycle performance and rate performance. The 1D nanotubes assembly and hollow interior endow this kind of material facilitate fast lithium ion and electron transport and accommodate the big volume change during the conversion reactions. Our study shows that low-cost transition metal silicate with rationally designed nanostructures can be promising anode materials for high capacity lithium-ion battery.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2015

Improved electrochemical performances of CuO nanotube array prepared via electrodeposition as anode for lithium ion battery

Graphical abstract: CuO nanotube array electrodes prepared by electrodeposition method exhibit an excellent lithium ion storage ability as anode of Li-ion battery. - Highlights: • CuO nanotube arrays are synthesized by an electrodeposition method. • CuO nanotube shows a high-rate performance. • CuO nanotube shows an excellent cycling performance. - Abstract: We report a facile strategy to prepared CuO nanotube arrays directly grown on Cu plate through the electrodeposition method. The as-prepared CuO nanotubes show a quasi-cylinder nanostructure with internal diameters of ca. ∼100 nm, external diameters of ca. ∼120 nm, and average length of ∼3 μm. As an anode for lithium ion batteries, the electrochemical properties of the CuO nanotube arrays are investigated by cyclic voltammetry (CV) and galvanostatic charge/discharge tests. Due to the unique nanotube nanostructure, the as-prepared CuO electrodes exhibit good rate performance (550 mAh g{sup −1} at 0.1 C and 464 mAh g{sup −1} at 1 C) and cycling performance (581 mAh g{sup −1} at 0.1 C and 538 mAh g{sup −1} at 0.5 C)

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2016

Synthesis and utilization of carbon nanotubes for fabrication of electrochemical biosensors

Graphical abstract: Carbon nanotubes. - Highlights: • This review discusses synthesis and applications of carbon nanotubes sensors. • The review summarizes contributions of carbon nanotube to electrochemical biosensor. • Good electrical conductivity makes carbon nanotubes a good material for biosensors. • Carbon nanotubes promotes electron transfer that aids biosensing of biomolecules. - Abstract: This review summarizes the most recent contributions in the fabrication of carbon nanotubes-based electrochemical biosensors in recent years. It discusses the synthesis and application of carbon nanotubes to the assembly of carbon nanotube-based electrochemical sensors, its analytical performance and future expectations. An increasing number of reviews and publications involving carbon nanotubes sensors have been reported ever since the first design of carbon nanotube electrochemical biosensors. The large surface area and good electrical conductivity of carbon nanotubes allow them to act as “electron wire” between the redox center of an enzyme or protein and an electrode's surface, which make them very excellent material for the design of electrochemical biosensors. Carbon nanotubes promote the different rapid electron transfers that facilitate accurate and selective detection of cytochrome-c, β-nicotinamide adenine dinucleotide, hemoglobin and biomolecules, such as glucose, cholesterol, ascorbic acid, uric acid, dopamine pesticides, metals ions and hydrogen peroxide.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Synthesis of Pt/rGO catalysts with two different reducing agents and their methanol electrooxidation activity

Highlights: • Pt/rGO catalysts were successfully synthesized using either NaBH{sub 4} or ethylene glycol. • Synthesis using NaBH{sub 4} could improve electrocatalytic towards methanol oxidation of Pt/rGO catalyst. • 40%Pt/rGO synthesized using NaBH{sub 4} showed the best electrocatalytic performance. - Abstract: The synthesis processes of Platinum (Pt) on reduced graphene oxide (rGO) catalysts from graphene oxide (GO) using two reducing agents including sodium borohydride and ethylene glycol is reported. Structure and morphology of Pt/rGO catalysts are characterized by X-ray powder diffraction, transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. Electrocatalytic methanol oxidation properties of these catalysts are evaluated by cyclic voltammetry and chronoamperometry. The results show that catalyst synthesized using sodium borohydride has a higher metallic Pt content and an improved catalytic performance in comparison to catalyst synthesized using ethylene glycol. Moreover, effect of Pt loading amount on electrocatalytic methanol oxidation performance of catalysts synthesized using sodium borohydride is systematically investigated. The optimal Pt loading amount on graphene is determined to be 40%.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Anodic electrochemical performances of MgCo{sub 2}O{sub 4} synthesized by oxalate decomposition method and electrospinning technique for Li-ion battery application

Highlights: • MgCo{sub 2}O{sub 4} was prepared by oxalate decomposition method and electrospinning technique. • Electrospun MgCo{sub 2}O{sub 4} shows the reversible capacity of 795 and 227 mAh g{sup −1} oxalate decomposition MgCo{sub 2}O{sub 4} after 50 cycle. • Electrospun MgCo{sub 2}O{sub 4} show good cycling stability and electrochemical performance. - Abstract: Magnesium cobalt oxide, MgCo{sub 2}O{sub 4} was synthesized by oxalate decomposition method and electrospinning technique. The electrochemical performances, structures, phase formation and morphology of MgCo{sub 2}O{sub 4} synthesized by both the methods are compared. Scanning electron microscope (SEM) studies show spherical and fiber type morphology, respectively for the oxalate decomposition and electrospinning method. The electrospun nanofibers of MgCo{sub 2}O{sub 4} calcined at 650 °C, showed a very good reversible capacity of 795 mAh g{sup −1} after 50 cycles when compared to bulk material capacity of 227 mAh g{sup −1} at current rate of 60 mA g{sup −1}. MgCo{sub 2}O{sub 4} nanofiber showed a reversible capacity of 411 mAh g{sup −1} (at cycle) at current density of 240 mA g{sup −1}. Improved performance was due to improved conductivity of MgO, which may act as buffer layer leading to improved cycling stability. The cyclic voltammetry studies at scan rate of 0.058 mV/s show main cathodic at around 1.0 V and anodic peaks at 2.1 V vs. Li.

36 MATERIALS SCIENCE↗
DOE OSTI2016

SnO and SnO·CoO nanocomposite as high capacity anode materials for lithium ion batteries

Highlights: • The preparation methods are simple, low cost and can be scaled up for large production. • SnO is cheap, non-toxic and eco-friendly. • SnO shows high reversible capacity (Theoretical reversible capacity: 875 mA h g{sup −1}). • We showed high reversible capacity and columbic efficiency for SnO and SnO based composites. • We addressed the capacity degradation by introducing secondary phase (CoO and CNT etc.) - Abstract: We prepared SnO nanoparticles (SnO–S) and SnO·CoO nanocomposites (SnO·CoO–B) as anodes for lithium ion batteries (LIBs) by chemical and ball-milling approaches, respectively. They are characterized by X-ray diffraction and TEM techniques. The Li- storage performance are evaluated by galvanostatic cycling and cyclic voltammetry. The SnO–S and SnO·CoO–B showed improved cycling performance due to their finite particle size (i.e. nano-size) and presence of secondary phase (CoO). Better cycling stability is noticed for SnO·CoO–B with the expense of their reversible capacity. Also, addition of carbon nanotubes (CNT) to SnO–S further improved the cycling performance of SnO–S. When cycled at 60 mA g{sup −1}, the first-cycle reversible capacities of 635, 590 and 460 (±10) mA h g{sup −1} are noticed for SnO–S, SnO@CNT and SnO·CoO–B, respectively. The capacity fading observed are 3.7 and 1.8 mA h g{sup −1} per cycle for SnO–S and SnO@CNT, respectively; whereas 1–1.2 mA h g{sup −1} per cycle for SnO·CoO–B. All the samples show high coulombic efficiency, 96–98% in the range of 5–50 cycles.

36 MATERIALS SCIENCE↗
DOE OSTI2016

A contrastive study of three graphite anodes in the piperidinium based electrolytes for lithium ion batteries

Graphical abstract: The fitting results of R{sub sei} and R{sub ct} of three graphite/Li cells. Besides three graphite/Li cells show the similar R{sub sei}, the NG198/Li cell demonstrates a higher R{sub ct} value in all test temperatures. Especially, the R{sub ct} at 333 K is even up to 355.8 Ω cm{sup 2}. Obviously, the narrow distribution of edge plane for NG198 caused this result, and then greatly restricts its cell capacity. By contrast, CMB with bigger specific surface area and more Li{sup +} insertion points shows lower resistance at room temperature, which should help to improve its capacity. - Highlights: • SEI film is closely related to graphite structures and formation temperature. • The graphite with bigger surface area and more Li{sup +} insertion points behaves better. • The graphite with narrow edge plane is uncompetitive for ionic liquid electrolyte. - Abstract: The electrochemical behaviors of natural graphite (NG198), artificial graphite (AG360) and carbon microbeads (CMB) in an ionic liquid based electrolyte are investigated by cyclic voltammetry (CV). The surface and structure of three graphite materials are characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD) before and after cycling. It is found that solid electrolyte interface (SEI) is closely related to graphite structure. Benefiting from larger specific surface area and more dispersed Li{sup +} insertion points, CMB shows a better Li{sup +} insertion/de-insertion behavior than NG198 and AG360. Furthermore, electrochemical impedance spectra (EIS) prove that the SEI of different graphite electrodes has different intrinsic resistance and Li{sup +} penetrability. By comparison, CMB behaves better cell performances than AG360, while the narrow edge plane makes NG198 uncompetitive as a potential anode for the ionic liquids (ILs)-type Li-ion battery.

36 MATERIALS SCIENCE↗
DOE OSTI2016

New anthracene-based-phtalocyanine semi-conducting materials: Synthesis and optoelectronic properties

Highlights: • Synthesis of tow phtalocyanines based on the anthracene and tetrazole. • Semi-conducting supramolecular material. • Good PL quantum yield. • The film morphology of the phtalocynine containing tetrazole group enhanced the carrier mobility. - Abstract: A new anthracene-based semi-conducting phtalocyanines AnPc and AnPc-Tr were synthesized in solvent-free conditions. The supramolecular structure of these compounds was confirmed by NMR and FT-IR spectroscopies. Their optical properties were investigated by UV–vis and photoluminescence spectroscopies. The optical gaps were estimated from the absorption-onsets films, and the obtained values were of 1.50 eV and 1.47 eV for AnPc-Tr and AnPc respectively. In solid state, a weaker π–π-interactions of conjugated systems were obtained in the case of AnPc-Tr in comparison with AnPc. This behavior was explained by steric hindrance of triazol groups, which decrease the planarity of macromolecular structure. The HOMO and LUMO levels were estimated using cyclic voltammetry analysis; two phtalocyanine derivatives show a comparable ionization potential. The phtalacyanine containing triazole groups (AnPc-Tr) reveals a higher electron affinity in comparison with AnPc. Single-layer diode devices were fabricated and showed relatively low turn-on voltages.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Immobilization of ruthenium phthalocyanine on silica-coated multi-wall partially oriented carbon nanotubes: Electrochemical detection of fenitrothion pesticide

Highlights: • Hybrid material, SiO{sub 2}/MWCNTs containing ruthenium phthalocyanine (RuPc) synthesized in situ. • Silica containing multi-walled carbon nanotube partially oriented. • Determination of pesticide fenitrothion in orange juice. - Abstract: This paper reports on the determination of the pesticide fenitrothion using a glassy carbon electrode modified with silica-coated, multi-walled, partially oriented carbon nanotubes, SiO{sub 2}/MWCNTs, containing ruthenium phthalocyanine (RuPc) synthesized in situ. The hybrid SiO{sub 2}/MWCNTs/RuPc material was characterized by UV–vis absorption spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM) and differential pulse voltammetry. The modified electrode showed well-defined peaks in the presence of fenitrothion in acetate buffer, pH 4.5, with a sensitivity of 0.0822 μA μM{sup −1} mm{sup −2} and a detection limit of 0.45 ppm. Notably, the modified SiO{sub 2}/MWCNTs/RuPc electrodes with did not suffer from significant influences in the presence of other organophosphorus pesticides during the determination of the fenitrothion pesticide. Moreover, this modified electrode showed excellent performance in the determination of fenitrothion in orange juice.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Nickel/silicon core/shell nanosheet arrays as electrode materials for lithium ion batteries

Highlights: • Ni nanosheet arrays is the core and Si layer is the shell. • Ni nanosheet arrays act as a three-dimensional current collector to support Si. • Ni nanosheet arrays can improve the conductivity and stability of the electrode. • Ni/Si nanosheet arrays exhibit excellent cyclic and rate performance. - Abstract: Ni/Si core/shell nanosheet arrays are proposed to enhance the electrochemical lithium-storage properties of silicon. The arrays are characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The arrays are micro-sized in height, which are constructed by interconnected Ni nanosheet as the core and Si coating layer as the shell. The electrochemical properties as anode materials of lithium ion batteries are investigated by cyclic voltammetry (CV) and galvanostatic charge-discharge tests. The arrays can achieve high reversible capacity, good cycle stability and high rate capability. It is believed that the enhanced electrochemical performance is attributed to the electrode structure, because the interconnected Ni nanosheet can act as a three-dimensional current collector, and it has the ability of improving the electrode conductivity, enlarging the electrochemical reaction interface, and suppressing the electrode pulverization.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Investigation of super-capacitive nature of reduced graphene oxide nano mesh grown over 18 k gold foil using wings of Parides iphidamas as biological template

Highlights: • Novel rGO nano mesh (rGONM) like assembly was fabricated using bio-template method. • rGONM pattern exhibit nano-ridges (40 nm) and ribs (25 nm) resembling fishing net. • Super-capacitor performances of rGO and rGONM coated Au substrates were evaluated. • rGO-Au and rGONM-Au revealed specific capacitances of 291 and 418 F/g respectively. - Abstract: This paper deals with the fabrication of novel, reduced graphene oxide nano mesh (rGONM) patterns with longitudinal nano-ridges and transverse nano-ribs using nano tubular structures found on the scales of Parides iphidamas, a butterfly species as biological template. Raman spectra, EDAX and FTIR results confirm the obtained mesh-like morphology that comprises only reduced graphene oxide (rGO). Further, super-capacitor performances of rGO and rGONM-coated gold substrates have been evaluated using cyclic-voltammetry (CV), galvanostatic charge-discharge cycle (GCD) and electrochemical impedance spectroscopic (EIS) analysis. A characteristic rectangular curve obtained from the CV of rGO and rGONM-coated gold electrodes display specific capacitances of 291 F/g and 418 F/g respectively at a scan rate of 5 mV/s. The results obtained from EIS support the superior nature of rGONM-coated electrode against rGO system, suggesting the use of rGONM-Au as a potential candidate for electrochemical super capacitor applications.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2018

Ultrasensitive and selective non-enzymatic electrochemical glucose sensor based on hybrid material of graphene nanosheets/graphene nanoribbons/nickel nanoparticle

Highlights: • Nickel nanoparticles incorporated graphene nanosheets/graphene nanoribbons (GS/GNR/Ni) composite was synthesized by in-situ chemical reduction route and the as prepared GS/GNR/Ni modified glassy carbon electrode (GCE) was applied to detect glucose. • The fabricated GS/GNR/Ni/GCE modified electrode exhibits outstanding performance for non-enzymatic glucose sensing with sensitivity (2.3 mA/mM cm{sup 2}), linear range (5 nM - 5 mM) and detection limit (2.5 nM). • GS/GNR/Ni/GCE modified electrode exhibited a high selectivity towards glucose against the interferents, such as ascorbic acid (AA), uric acid (UA), dopamine and sucrose. - Abstract: A fast, highly sensitive and selective non-enzymatic electrochemical glucose sensor based on graphene sheet/graphene nanoribbon/nickel nanoparticles (GS/GNR/Ni) hybrid material modified electrode was fabricated. The hybrid material was synthesized via facile in-situ chemical reduction and characterized by X-ray diffraction, transmission electron microscopy, Raman spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The GS/GNR/Ni/GCE showed high electrochemical activity towards the oxidation of glucose in a 0.1 M NaOH solution. At an applied potential of +0.5 V, it displayed wide linear amperometric response towards glucose from the range of 5 nM–5 mM, with a detection limit of 2.5 nM and sensitivity of 2.3 mA/mM cm{sup 2}. Moreover, the modified electrode was relatively insensitive to commonly interfering species such as dopamine, ascorbic acid, sucrose, uric acid and Cl{sup −} ions. The fabricated sensor with better reproducibility, good long term stability, makes it a promising electrode for the development of effective glucose sensor.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2018

Improvement on the catalytic activity of the flexible PEDOT counter electrode in dye-sensitized solar cells

Highlights: • The catalytic activity of PEDOT electrode can be tuned by varying deposited time. • A highly effective Pt/PEDOT electrode was also prepared. • The DSSCs using Pt/PEDOT counter electrode shows high efficiency of 7.90%. - Abstract: A flexible Poly (3, 4-ethylenedioxythiophene) (PEDOT) electrode on indium-doped tin oxide coated polyethylene naphthalate (ITO-PEN) substrate is prepared by electrochemical methods for dye-sensitized solar cells (DSSCs) as counter electrode. The impact of deposition time on the catalytic activities of the flexible PEDOT electrode towards the iodide redox couple has been investigated by cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and Tafel polarization curve measurements. After optimization, the DSSCs using PEDOT counter electrode deposited 80 s shows power conversion efficiency (PCE) of 7.18%, close to than the Pt counter electrode based counterpart (7.56%). To further improve the catalytic activity of PEDOT, Pt/PDEOT composite catalyst is synthesized. And the DSSCs with the Pt/PDEOT composite CE generates a high PCE of 7.90%.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Synthesis and electrochemical properties of silver dendrites and silver dendrites/rGO composite for applications in paracetamol sensing

Highlights: • Synthesis of Ag dendrites and GO/Ag dendrites composites by Galvanic Replacement method. • Ag dendrites are wrapped over graphene sheets. • High sensitivity (10.046 μA cm{sup −2} mM{sup -1)} and lower limit of detection of 0.025 μM for sensing of Paracetamol. - Abstract: Electrochemical sensors are one of the important applications of electrochemistry. In this paper, synthesis, characterization and application of Silver Dendrites and Silver Dendrites/rGO sensors for simple and fast determination of Paracetamol are described. Silver dendrites and their composite with graphene oxide were synthesized by galvanic replacement method. The synthesized samples were characterized by XRD, SEM and TEM. XRD reveals the FCC structure of silver and TEM images show the formation of dendritic silver wrapped in the graphene sheets. The Electrochemical paracetamol sensing properties of these samples were tested using cyclic voltammetry and chronoamperometry. The silver dendrites exhibit a sensitivity of 2.807 × 10{sup 5}μA/mM/g and a lower detection limit of 2.5 μM, whereas, the composite with graphene oxide exhibits a high sensitivity of 2.511 × 10{sup 6}μA /mM/g with a lower detection limit of 0.025 μM.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Facile synthesis and photocatalytic activity of Ag3PO4 decorated MoS2 nanoflakes on carbon fiber cloth

Highlights: • A novel CC@MoS{sub 2}-Ag{sub 3}PO{sub 4} heterostructure is fabricated by a facile method. • The growth process of CC@MoS{sub 2} is investigated. • The heterostructure displays an excellent photocatalytic property. • Cyclic Voltammetry is utilized to investigate the photocatalytic mechanism. - Abstract: A novel CC@MoS{sub 2}-Ag{sub 3}PO{sub 4} heterostructure, composed of Ag{sub 3}PO{sub 4} nanoparticles decorated MoS{sub 2} nanosheets on carbon fiber cloth (CC), is fabricated by a simple hydrothermal method and a successive ionic layer absorption reaction. The CC@MoS{sub 2}-Ag{sub 3}PO{sub 4} heterostructure displays an excellent photocatalytic activity of ∼96% degradation rate for RhB solution under simulated daylight, which is more than 10 times as much as that of pure Ag{sub 3}PO{sub 4} or MoS{sub 2}. The CC@MoS{sub 2}-Ag{sub 3}PO{sub 4} heterostructure with optimized photoactivity is investigated by optical and electrochemical measurements. The CC@MoS{sub 2}-Ag{sub 3}PO{sub 4} heterostructure can not only broaden the photoresponse range of MoS{sub 2}, but also alleviate the photodegradation of Ag{sub 3}PO{sub 4}, and the easily separated CC provides a proper conductive substrate and rapid charge transfer channels. The probable photocatalytic mechanism of CC@MoS{sub 2}-Ag{sub 3}PO{sub 4} heterostructure is discussed in detail. Therefore, the CC@MoS{sub 2}-Ag{sub 3}PO{sub 4} heterostructure with high efficient photocatalytic performance and easy separation is a promising photocatalytic material.

36 MATERIALS SCIENCE↗