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To explore the effects of the introduction order of calcium sources and the bacteria-to-calcium ratio on the microbially induced calcium carbonate precipitation (MICP) product CaCO3 and to achieve the regulation of CaCO3 crystal morphology, the mineralisation products of MICP were compared after combining bacteria and calcium at ratios of 1/9, 2/9, 3/9, 4/9, 5/9, and 6/9. A bacterial solution was combined with a urea solution in two calcium addition modes: calcium-first and calcium-later modes. Finally, under the calcium-first addition method, the output of high-purity vaterite-type CaCO3 was achieved at bacteria-to-calcium ratios of 2/9 and 3/9; under the calcium-later addition method, the output of calcite-type CaCO3 could be stabilised, and the change in the bacteria-to-calcium ratio did not have much effect on its crystalline shape. [ABSTRACT FROM AUTHOR]

High capacity electrodes are demanded to increase the energy and power density of lithium ion batteries. However, the cycling and rate properties are severely affected by the large volume changes caused by the lithium insertion and extraction. Structured electrodes with mechanically stable scaffolds are widely developed to mitigate the adverse effects of volume changes. Tin, as a promising anode material, receives great attentions because of its high theoretic capacity. There is a critical value of tin particle size above which tin anodes readily crack, leading to low cyclability. The electrode design using mechanical scaffolds must retain tin particles below the critical size and concurrently enable high volumetric capacity. It is a challenge to guarantee the critical size for high cyclability and space utilization for high volumetric capacity. This study provides a highly conductive TiN nanotubes array with submicron diameters, which enable thin tin coating without sacrificing the volumetric capacity. Such a structured electrode delivers a capacity of 795 mAh g Sn − 1 (Sn basis) and 1812 mAh c m el − 3 (electrode basis). The long-term cycling shows only 0.04% capacity decay per cycle. [ABSTRACT FROM AUTHOR]

Porous poly(3,4-ethylenedioxythiophene) (PEDOT) nanoarray used for flexible supercapacitor has been prepared to investigate its electrochemical capacitance performance. Well-aligned titania (TiO 2 ) and titanium nitride (TiN) nanotube array was fabricated by an anodization, crystallization, nitridation processes. PEDOT-TiO 2 and PEDOT-TiN nanoarray hybrid was fabricated by coating PEDOT on nanotube walls of TiO 2 and TiN through a pulse voltammetry electrodeposition process. PEDOT nanopore array was fabricated through HF corrosion of TiN from PEDOT-TiN. The morphology and microstructure of PEDOT-TiO 2 , PEDOT-TiN and PEDOT were characterized by scanning electron microscopy and Raman spectroscopy. The electrochemical capacitance was investigated by cyclic voltammetry and galvanostatic charge–discharge measurements. PEDOT-TiO 2 and PEDOT-TiN showed heterogeneous coaxial nanotube structure. PEDOT exhibited free-standing nanopore array structure. The specific capacitance of PEDOT-TiN nanoarray hybrid was determined to be 393.1 F g −1 at a current density of 1.0 mA cm −2 , presenting much higher capacitance than PEDOT-TiO 2 nanoarray hybrid (128.7 F g −1 ) and PEDOT nanopore array (109.3 F g −1 ). All-solid-state flexible supercapacitor was constructed using supple electrode of PEDOT-TiN nanoarray hybrid and polyvinyl alcohol gel electrolyte of sulphuric acid. The volume specific capacitance, energy and power density were determined to be 4.08 F cm −3 , 2.26 mW h cm −3 and 250 mW cm −3 at a high output voltage of 2.0 V and a current density of 10 mA cm −2 . PEDOT-TiN nanoarray hybrid exhibited the effective energy storage in flexible supercapacitor application. [ABSTRACT FROM AUTHOR]

Both polypyrrole–titanium nitride (PPy–TiN) and polypyrrole–titania (PPy–TiO2) nanotube hybrids have been prepared by incorporating electroactive polypyrrole into well-aligned titanium nitride and titania nanotube arrays through a normal pulse voltammetry deposition process. Microstructure characterization shows that the polypyrroles have been fully coated on the titanium nitride and titania nanotube arrays to form coaxial heterogenous nanohybrids. The galvanostatic charge–discharge measurements indicate that the PPy–TiN and PPy–TiO2 nanotube hybrids have specific capacitances of 1265 and 382 F g−1 at a current density of 0.6 A g−1. Both nanotube hybrids have similar cyclability, exhibiting stable capacitances of 459 and 72 F g−1 after 2000 cycles at a high current density of 15 A g−1. The highly conductive titanium nitride substrate can promote the electrochemical capacitance of polypyrrole more significantly, as compared to the titania semiconductor, contributing to a higher supercapacitance performance of PPy–TiN. This indicates that PPy–TiN nanotube hybrids can be more suitable to act as supercapacitor electrode materials. [ABSTRACT FROM AUTHOR]

In this study, the polypyrrole-titania nanotube hybrid has been synthesized for an electrochemical supercapacitor application. The highly ordered and independent titania nanotube array is fabricated by an electro-oxidation of titanium sheet through an electrochemical anodization process in an aqueous solution containing ammonium fluoride, phosphoric acid and ethylene glycol. The polypyrrole-titania nanotube hybrid is then prepared by electrodepositing the conducting polypyrrole into well-aligned titania nanotubes through a normal pulse voltammetry deposition process in an organic acetonitrile solution containing pyrrole monomer and lithium perchlorate. The morphology and microstructure of polypyrrole-titania nanotube hybrid are characterized by scanning electron microscopy, infrared spectroscopy and Raman spectroscopy. The electrochemical capacitance performance is determined by cyclic voltammetry and charge/discharge measurement. It indicates that the polypyrrole film can been uniformly deposited on both surfaces of titania nanotube walls, demonstrating a heterogeneous coaxial nanotube structure. The specific capacitance of polypyrrole-titania nanotube hybrid is determined to be 179 F g based on the polypyrrole mass. The specific energy and specific power are 7.8 Wh kg and 2.8 kW kg at a constant charge/discharge current of 1.85 mA cm, respectively. The retained specific capacitance still keeps 85% of the initial capacity even after 200 cycle numbers. This result demonstrates the satisfying stability and durability of PPy-TiO nanotube hybrid electrode in a cyclic charge/discharge process. Such a composite electrode material with highly ordered and coaxial nanotube hybrid structure can contribute high energy storage for supercapacitor applications. [ABSTRACT FROM AUTHOR]

• Investigation of high-temperature pore pressure in concrete slabs designed to 94 MPa. • Larger pore pressure in reinforced concrete slabs than that in plain concrete slabs. • The "moisture clog" formed by vapor been at the 50 mm deep in concrete slabs. • The reduction of pore pressure by adding the polypropylene fibers in concrete slabs. • The positive correlation between pore pressure and concrete strength. Based on the pore pressure test of the cylindrical specimens at high temperatures, the pore pressure in the reinforced slabs (390 (L) × 390 (W) × 120 (H) mm) made of high strength concrete and high performance concrete (HSC/HPC) exposed to elevated temperatures was studied, and the effects of elevated temperatures and heating duration on the pore pressure in heated HSC/HPC were presented. Four types of slabs made of C80 HPC including plain HPC slabs (HPCS), plain rebar-reinforced HPC slabs (RHPCS), PP fiber-reinforced HPC slabs (PPHPCS), rebar-PP fiber-reinforced HPC slabs (RPPHPCS) were tested. The pore pressure results indicate that the heating rate of the concrete slabs gradually decreases with increase of the depth from the heated surface. The 50 mm depth in slabs may be a "moisture clog", which is consistent with the relevant numerical results. Comparison with tensile strength shows that the pore pressure is not the only cause of spalling. According to few related reports, studies on the effects of the rebar mesh on the pore pressure and spalling of slabs have showed that spalling in RHPCS is not as severe as that in HPCS at high temperatures, but the pore pressure of rebar-reinforced concrete slabs is greater compared to the plain concrete slabs. Adding PP fibers can effectively prevent the occurrence of spalling and reduce the pore pressure in the heated slabs. It was determined that the rebar mesh and PP fibers reduce the occurrence of spalling, which provides ideas and test data for improving the fire resistance (anti-spalling) of HSC/HPC. [ABSTRACT FROM AUTHOR]

Exploring cheap and efficient cocatalysts is particularly important for a photoanode during photoelectrochemical (PEC) water splitting. Herein, we demonstrate that composite CoOx/CuO cocatalyst could efficiently enhance the oxygen evolution activity of BiVO4. The onset potential of BiVO4 shifts negatively from 0.42 to 0.38 V vs. the reversible hydrogen electrode (RHE), and the photocurrent of BiVO4 increases from 0.42 mA cm−2 to 1.58 mA cm−2 at 1.23 V vs. RHE, which increases by about 3.76 times. It was confirmed by subsequent electrochemical and physical characterization that the charge separation and injection efficiency were improved, and the IPCE was also improved. Systematic studies indicate that composite CoOx/CuO cocatalyst exhibits better performance than the single CoOx or CuO cocatalyst for promoting the separation of electron‐hole, and accelerating the surface water oxidation reaction. [ABSTRACT FROM AUTHOR]

The ternary nanocomposite of polyaniline/carbon/titanium nitride (PANI/C/TiN) nanowire array (NWA) is fabricated as electroactive electrode material for flexible supercapacitor application. Firstly, TiN NWA is formed through ammonia nitridation treatment of TiO 2 NWA, which is synthesized via seed-assisted hydrothermal reaction. PANI/C/TiN NWA is then formed through sequentially coating carbon and PANI on the surface of TiN NWA. PANI/C/TiN NWA has unique shell/shell/core architecture, including a core layer of TiN NWA with a diameter of 40–160 nm and a length of 1.5 μm, a middle shell layer of carbon with a thickness of about 6.0 nm and an external surface layer of PANI with a thickness of 20–50 nm. PANI/C/TiN NWA provides ion diffusion channel at interspaces between the neighboring nanowires and electron transfer route along independent nanowires. The carbon shell layer is able to protect TiN NWA from electrochemical corrosion during charge/discharge process. PANI/C/TiN NWA displays high specific capacitance of 1093 F g −1 at 1.0 Ag −1 , and good cycling stability with a capacity retention of 98% after 2000 cycles, presenting better supercapacitive performance than other integrated nanocomposites of C/PANI/TiN, PANI/TiN and PANI/C/TiO 2 NWA. Such a ternary nanocomposite of PANI/C/TiN NWA can be used as an electrode material of flexible supercapacitors. [ABSTRACT FROM AUTHOR]

The electroactive polyaniline (PANI) and manganese oxide (MnO) were integrated with titanium nitride (TiN) nanowire array (NWA) to form PANI/MnO/TiN ternary nanocomposite for supercapacitor application. TiN NWA was prepared via a seed-assisted hydrothermal synthesis and ammonia nitridization process. The electroactive MnO and PANI was layer-by-layer coated on TiN NWA to form heterogeneous coaxial structure through a stepwise electrodeposition process. Scanning electron micrographs revealed that the well-separated TiN NWA was composed of well-distributed nanowires with diameters in the range of 10-30 nm and a total length of 1.5 μm. A villiform MnO layer with a thickness of 10-20 nm covered on TiN NWA to form MnO/TiN NWA composite. The coral-like PANI layer with thicknesses in the range of 20-50 nm covered on the above MnO/TiN NWA to form PANI/MnO/TiN NWA. Electrochemical measurements showed that a high specific capacitance of 674 F g at a current density of 1 A g (based on total mass of PANI/MnO) was obtained for PANI/MnO/TiN NWA ternary nanocomposite, which was much higher than that of PANI/MnO/carbon-cloth composites reported previously. This ternary nanocomposite also showed a good rate and cycling stability. Moreover, in comparison with PANI/TiN NWA or MnO/TiN NWA, the specific capacitance of PANI/MnO/TiN NWA was obviously enhanced due to the extra pseudocapacitance contribution and the effective surface area of coral-like PANI layer, showing the advantage of manipulating the heterogeneous coaxial configuration between PANI and MnO for fundamentally improved capacitive performance. These results demonstrated that PANI/MnO/TiN NWA ternary nanocomposite was a promising candidate electrode material for supercapacitor application. [ABSTRACT FROM AUTHOR]

In this study, the effects of soybean-urease-induced carbonate precipitation on a high-temperature damage repair of concrete were explored. C50 concrete specimens were exposed to high temperatures from 300 to 600 °C, then cooled to an ambient temperature and repaired by two different methods. The influences of the damage temperature and repair methods on surface film thickness, average infrared temperature increase, water absorption, and compressive strength were investigated. Scanning electron microscopy (SEM) images were carried out to further study the mechanism involved. The results revealed that the white sediments on the surface of the repaired specimens were calcium carbonate (CaCO3) and calcium oxalate (CaC2O4). The surface film thickness reached up to 1.94 mm after repair. The average infrared temperature increase in the repaired specimens at different damage temperatures was averagely reduced by about 80% compared with that before the repair. It showed more obvious repair effects at higher temperatures in water absorption and compressive strength tests; the compressive strength of repaired specimens was 194% higher than that before repairs at 600 °C. A negative pressure method was found to be more effective than an immersion method. This study revealed the utilization of SICP on repairing high-temperature damage of concrete is feasible theoretically. [ABSTRACT FROM AUTHOR]

Highlights: [•] TiN nanoarray is formed by a nitridation process of TiO2 in ammonia atmosphere. [•] TiN nanoarray exhibits much higher EDLC capacitance than TiO2 nanoarray. [•] The specific capacitance of TiN nanoarray achieves a high level of 99.7mFcm−2. [•] A flexible solid-state supercapacitor is constructed by TiN nanoarray and PVA gel. [Copyright &y& Elsevier]

• A novel TiO 2 @TiN nanocomposite enhances the extracellular electron transfer of bacteria. • TiO 2 @TiN nanocomposites reduce charge transfer resistance at biofilm-electrode interfaces. • The biosynthesis of electron transfer mediators is enhanced by a TiO 2 @TiN nanocomposite. • Cytochrome c expression can be increased by a TiO 2 @TiN nanocomposite. Extracellular electron transfer (EET) allows microorganisms to perform anaerobic respiration using insoluble electron acceptors, including minerals and electrodes. EET-based applications require efficient electron transfer between living and non-living systems. To improve EET efficiency, the TiO 2 @TiN nanocomposite was used to form hybrid biofilms with Shewanella loihica PV-4 (PV-4). Chronoamperometry showed that peak current was increased 4.6-fold via the addition of the TiO 2 @TiN nanocomposite. Different biofilms were further tested in a dual-chamber microbial fuel cell. The PV-4 biofilm resulted a maximum power density of 33.4 mW/m2, while the hybrid biofilm of the TiO 2 @TiN nanocomposite with PV-4 yielded a 92.8% increase of power density. Electrochemical impedance spectroscopy analyses showed a lower electron-transfer resistance in the hybrid biofilm. Biological measurements revealed that both flavin secretion and cytochrome c expression were increased when the TiO 2 @TiN nanocomposite presented. These results demonstrated that the TiO 2 @TiN nanocomposite could synergistically enhance the EET of PV-4 through altering its metabolism. Our findings provide a new strategy for optimizing biotic-abiotic interactions in bioelectrochemical systems. [ABSTRACT FROM AUTHOR]

The performance of TiO 2 nanosheets (TiO 2 -NSs) modified carbon paper anode (TiO 2 -NSs/CP) in S. loihica PV-4 inoculated MFCs is greatly improved by intentional N doping of TiO 2 -NSs to modulate its electronic properties. TiO 2 -NSs/CP is calcined in NH 3 atmosphere at different temperatures (T = 400, 500, 600 and 700 °C) to obtain N doped anodes (T-NTiO 2 -NSs/CP, T represents temperature), in which 600-NTiO 2 -NSs/CP electrode show best performance with the maximum output power density increased by 196% and 50% compared to that from the bare CP and TiO 2 -NSs/CP electrodes respectively. The surface morphology, structure and electrochemical activity are characterized by FESEM, XRD, Raman, XPS, CVs and EIS. The results show that heating in NH 3 atmosphere keep surface morphology and bio-affinity of the electrode. The midpoint potential E m (−0.29 V) of outer membrane c-type cytochromes (OMCs) at 600-NTiO 2 -NSs/CP anode is in accordance with that at TiO 2 -NSs/CP. However, 600-NTiO 2 -NSs/CP electrode had smaller charge transfer resistance, more positive flat-band potential and larger transient charge storage capacity than untreated electrode due to modulation of the electronic structure via N doping, which all are favorable to interfacial electron transfer from OMCs to underlying electrode. The method is simply and efficient, and could be extended to other nano-semiconductor modified electrodes for superior MFC anodes. [ABSTRACT FROM AUTHOR]

• Magnetite-GO were successfully prepared by attaching magnetite nanoparticles on the surface of GO. • GO were magnetically aligned through the application of an external magnetic field. • GO alignment improved both the flexural strength and elastic modulus of the cement paste. This study fabricated magnetic nanocomposites by attaching magnetite nanoparticles on the surface of graphene oxide (GO). Through the application of an external magnetic field with a strength of 0.045 T, GO nanosheets were found to be aligned in the cement paste specimen. According to polarized Raman spectroscopic study, the orientation factor of aligned and randomly oriented GO were 0.66 and 0.53, respectively. Further, the GO alignment contributed to mechanical properties. At 28 d, the flexural strength and flexural modulus of elasticity of specimen with aligned GO was improved by 40.82 and 90.93 %, respectively, compared to that of blank cement paste without GO. In addition, compared to the cement paste with randomly oriented GO, the specimen with aligned GO exhibited an increase of 12.61 and 11.86 %, in flexural strength and flexural modulus of elasticity, respectively. This study provides insights into the design of GO incorporated cement-based materials by carefully manipulating magnetic properties of GO. [ABSTRACT FROM AUTHOR]

Understanding the photocatalytic reductive dehalogenation mechanism of halogenated aromatic pollutants is of great research value. However, the proton source in the photocatalytic dehalogenation process of representative halogenated aromatic pollutants by TiO 2 is not clear. In this study, the TiO 2 surface was modified by hydrochloric acid, sodium hydroxide, and sodium fluoride to obtain TiO 2 samples with different hydroxyl groups. It was found that the hydroxyl groups on the surface of TiO 2 affects the sequence of proton and electron transfer in dehalogenation. The abundance of hydroxyl groups on the surface of TiO 2 can accelerate the reductive dehalogenation process of representative halogenated aromatic pollutants. The kinetic solvent isotope effect was used to study the proton-coupled electron transfer process in the reaction. It shows that the enriching of protons on TiO 2 bridging oxygen (bridging hydroxyl groups) is conducive to the rapid step of protonation of the reactant, and subsequent proton and electron transfer. On the contrary, the bridging hydroxyl groups can be removed by reacting with strongly basic sodium hydroxide and sodium ions can occupy the bridging oxygen. The substitution of bridging oxygen by fluorine ions can also lead to the destruction of bridge hydroxyl groups. Significantly, the absence of bridging hydroxyl groups on titanium dioxide will lead to the dehalogenation of representative halogenated aromatic pollutants initiated by electron transfer. This study is helpful to understand dehalogenation reaction paths catalyzed by TiO 2. [Display omitted] • Regulation of surface hydroxyl groups on TiO 2 by acid, base, and NaF modification. • Debromination induced by proton transfer on TiO 2 with abundant bridging hydroxyls. • Debromination initiated by electron transfer on TiO 2 lacking bridging hydroxyls. [ABSTRACT FROM AUTHOR]

• α-Fe 2 O 3 photoanode was modified by antimony. • Ethylene glycol was an excellent solvent for antimony treatment. • The α-Fe2O3 photoanodes combined with antimony post-treatment showed the best photoelectrochemical performance. The photoelectrochemical (PEC) performance of α-Fe 2 O 3 photoanode suffers from the high carrier recombination rate and the short hole diffusion distance. Enhancing its carrier transport is an important way to improve its performance. In this paper, α-Fe 2 O 3 films were synthesized by hydrothermal method and further optimized by ethylene glycol assisted antimony treatment. Antimony treatment can be divided into pre-annealing and post-annealing treatment. The photocurrent of hematite photoanode post-annealing treated by Sb dissolved in ethylene glycol photoanode can reach to 1.18 mA cm−2, which is 1.6 times higher than that of bare α-Fe 2 O 3 photoanode. The improvement of PEC performance is mainly attributed to the effective inhibition of carrier recombination by antimony treatment. In addition, the slope of the Mott-Schottky curves of Fe 2 O 3 can be obviously changed by antimony treatment, demonstrating the significant increase of carrier concentration. [ABSTRACT FROM AUTHOR]

The polypyrrole/titania/polyaniline (PPy/TiO 2 /PANI) coaxial nanotube hybrid has been prepared through a stepwise electrodeposition process for an electrochemical energy storage. Independent TiO 2 nanotube array was used as the framework, which was formed by anodizing titanium foil at 30 V in fluoride-containing water and ethylene glycol mixture solution. The PPy was selectively coated on the outer surface of TiO 2 nanotube walls to form PPy/TiO 2 through a normal pulse voltammetry electrodeposition process. The PANI was then coated on the inner surface of TiO 2 nanotube walls to form PPy/TiO 2 /PANI coaxial nanotube hybrid through a photoassisted cyclic voltammetry electrodeposition process. The morphology and microstructure feature of PPy/TiO 2 /PANI were characterized by field-emission scanning electron microscopy and Raman spectrum. The capacitance performance was conducted by cyclic voltammetry and galvanostatic charge–discharge measurements. PPy/TiO 2 /PANI coaxial nanotube hybrid with P/N-type doping properties exhibited a high specific capacitance of 497 F g −1 at a current density of 0.5 A g −1 and a potential window of −0.2 to 0.8 V in 1.0 M H 2 SO 4 solution. The capacitance declined from 267.9 to 193.7 F g −1 after 500 cycles at a high current density of 2.0 A g −1 , showing 72.3% capacitance retention and a good cycle stability for the promising supercapacitor application. [ABSTRACT FROM AUTHOR]

We report on a new nanocomposite material for electrochemical sensing of hydrogen peroxide using a titanium dioxide nanotube arrays modified with reduced graphene oxide onto which silver nanoparticles (AgNPs) were chemically deposited. Transmission electron microscopy, scanning electron microscopy, X-ray diffraction, and energy-dispersive X-ray and Raman spectroscopy were used to characterize its microstructure and morphology. The results demonstrated that the AgNPs were uniformly dispersed on the surface of the modified electrode which was investigated with respect to capability for sensing hydrogen peroxide (HO). Under optimized experimental condition, the electrode responds to HO with a sensitivity of 1152 μA mM cm at a working potential of −0.6 V. The current response is linearly related to the concentration of HO in the range from 50 to 15.5 mM (with a correlation coefficient of 0.9997), and the detection limit is 2.2 μM. The sensor exhibits good stability and excellent selectivity for HO. By immobilizing glucose oxidase on the surface of this electrode, a glucose biosensor was obtained that responds to glucose in the 0.5 to 50 mM concentration range. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

• GO can effectively suppress the pore structure coarsening of cement pastes during heat treatment. • Adding GO delays the compressive strengths loss of the cement pastes exposed to high temperatures. • The water bound in GO agglomerates is negligible, the interlaminar water content comprises approximately 0.06% of the total weight loss. This study investigated the high-temperature properties of cement pastes with graphene oxide (GO) agglomerates at temperatures of 105 °C, 200 °C, 300 °C, and 450 °C. Generally, at ambient temperatures, incorporating GO can refine the pore structures and crystal sizes of calcium hydroxide, which is beneficial for the thermal resistance of a cement paste. In this study, during heat treatment, it was found that the water bound in GO agglomerates is negligible (from conducting a weight loss analysis). The GO agglomerates suppress the pore structure coarsening of cement pastes. The pore structure is finer and the total porosity is reduced by 8.5% with incorporation of 0.04% (by weight) GO at 300 °C which is close to critical point of water. With incorporation of 0.04% by weight GO in cement pastes at 200 °C, 300 °C, and 450 °C, the residual compressive strengths are 9.28%, 12.63%, and 10.83% higher than that of a reference sample, respectively. [ABSTRACT FROM AUTHOR]

Highlights: [•] PANI/TiN core–shell nanowire arrays were prepared for supercapacitor application. [•] TiN nanowire arrays contributed to high surface area and low resistance for PANI. [•] PANI/TiN core–shell nanowire arrays exhibited much higher capacitance than PANI/TiO2. [Copyright &y& Elsevier]

A glucose biosensor has been fabricated by immobilizing glucose oxidase (GOx) on unhybridized titanium dioxide nanotube arrays using an optimized cross-linking technique. The TiO nanotube arrays were synthesized directly on a titanium substrate by anodic oxidation. The structure and morphology of electrode material were characterized by X-ray diffraction and scanning electron microscopy. The electrochemical performances of the glucose biosensor were conducted by cyclic voltammetry and chronoamperometry measurements. It gives a linear response to glucose in the 0.05 to 0.65 mM concentration range, with a correlation coefficient of 0.9981, a sensitivity of 199.6 μA mM cm, and a detection limit as low as 3.8 µM. This glucose biosensor exhibited high selectivity for glucose determination in the presence of ascorbic acid, sucrose and other common interfering substances. This glucose biosensor also performed good reproducibility and long-time storage stability. This optimized cross-linking technique could open a new avenue for other enzyme biosensors fabrication. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A polyaniline/titanium nitride (PANI/TiN) nanotube hybrid was prepared and used for an electrochemical supercapacitor application. Firstly, the well-aligned TiN nanotube array was prepared by anodization of titanium foil and subsequent nitridation through ammonia annealing. Then, PANI was deposited into TiN nanotube through the electrochemical polymerization process. The obtained PANI/TiN nanotube hybrid had an ordered porous structure. A high specific capacitance of 1,066 F g was obtained at the charge-discharge current density of 1 A g when only the mass of PANI was considered. The specific capacitance can even achieve 864 F g at 10 A g and still keep 93 % of the initial capacity after 200 cycles. An aqueous supercapacitor, consisting of two symmetric PANI/TiN nanotube hybrid electrodes and 1.0 M HSO electrolyte solution, showed the specific capacitance of 194.8 F g, energy density of 9.74 Wh kg, and power density of 0.3 kW kg. [ABSTRACT FROM AUTHOR]