Electron Transfer Distance Research Articles

Long distance electron transfer through the aqueous solution between redox partner proteins

Despite the importance of electron transfer between redox proteins in photosynthesis and respiration, the inter-protein electron transfer rate between redox partner proteins has never been measured as a function of their separation in aqueous solution. Here, we use electrochemical tunneling spectroscopy to show that the current between two protein partners decays along more than 10 nm in the solution. Molecular dynamics simulations reveal a reduced ionic density and extended electric field in the volume confined between the proteins. The distance-decay factor and the calculated local barrier for electron transfer are regulated by the electrochemical potential applied to the proteins. Redox partners could use electrochemically gated, long distance electron transfer through the solution in order to conciliate high specificity with weak binding, thus keeping high turnover rates in the crowded environment of cells.

A facile dissolved and reassembled strategy towards sandwich-like rGO@NiCoAl-LDHs with excellent supercapacitor performance

Metal organic frameworks hold great potential for high-performance supercapacitors owning to ultrahigh specific surface area and exceptional porosity. Nevertheless, the poor charge transfer kinetics and chemical instability in alkali medium still remain a significant challenge. Herein, a facile dissolved and reassembled strategy towards sandwich-like rGO@NiCoAl-LDHs is proposed to address these drawbacks. NiAl-LDHs can be used as an accumulator to accommodate and reassemble the cobalt ions dissolved from ZIF-67. Graphene could facilitate charge transfer and provide more active sites. Meanwhile, the sandwich-like structure could shorten the transfer distance of electrons and reduce the diffusion resistance of electrolyte. The electrochemical performance is drastically improved due to the enhancement of intrinsic activity reassembling from sandwich-like rGO@ZIF-67@NiAl-LDHs to rGO@NiCoAl-LDHs during cycle process. The electrode material delivers a superior specific capacity of 2291.6 F/g at 1 A/g in a three-electrode configuration. The assembled rGO@NiCoAl-LDHs//AC fulfills a high energy density of 91.4 Wh/kg at a power density of 875 W/kg. In a word, this dissolved and reassembled strategy could possess the huge prospect for energy-related devices.

Interfacial Electron Transfer from the Outer Membrane Cytochrome OmcA to Graphene Oxide in a Microbial Fuel Cell: Spectral and Electrochemical Insights

A microbial fuel cell (MFC) is able to convert waste energy into electricity, and its performance is mainly constrained by extracellular electron transfer (EET) at biological/inorganic interfaces. In this work, the interaction process between the microbe’s outer membrane cytochrome (OmcA) and graphene oxide (GO) is investigated in vitro to elucidate the EET mechanism in the MFC. The feasibility of the electron transfer from the purified OmcA to GO is examined by protein film voltammetry tests. Stopped flow analysis demonstrates that the EET kinetic process obeys the Michaelis–Menten equation and exhibits the characteristics of enzyme catalysis. The structural changes of OmcA/GO monitored by a circular dichroism spectroscopy combined with infrared spectroscopy techniques indicate that the formation of a hydrogen bond between the −NH2 group of the residues and the −COOH/–OH group of GO shortens the electron-transfer distance to mitigate the energy barrier. These results help to understand the EET mechanism ...

Uniformly distributed TiO2 nanorods on reduced graphene oxide composites as anode material for high rate lithium ion batteries

TiO2 nanorods uniformly distributed on reduced graphene oxide (rGO) were successfully synthesized via a facile sol-static self-assembled method followed by an alkali-heat treatment. The flexible rGO nanosheets can not only serve as the electric matrix to increase the conductivity of composite, but also offer large active area between the electrode material and electrolyte to facilitate electrolyte permeability and shortened distance for lithium ion diffusion and electron transfer. Detailed analysis on electrochemical kinetics manifests that the increased diffusion coefficiency and capacitive behaviors during the charging/discharging processes lead to fast insertion/extraction of lithium ions in the obtained TiO2 nanorods/rGO composite (TNGC). Consequently, the as-obtained TNGC exhibited a good electrochemical performance with a high cyclic stability (353.6 mA h g−1 after 100 cycles at a current density of 0.1 A g−1) and outstanding rate capacity (205.1 mA h g−1 at a current density of 2 A g−1) as lithium ion batteries anode material.

In-situ insertion of carbon nanotubes into metal-organic frameworks-derived α-Fe2O3 polyhedrons for highly sensitive electrochemical detection of nitrite

Achieving highly sensitive electrochemical detection of nitrite for the control of nitrite contamination is a constant challenge, therefore, exploring hierarchical nanostructured materials for electrochemical detection with high activity is a vital importance. In the present study, we prepared the highly ordered MOFs-derived α-Fe2O3/CNTs hybrids through in-situ insertion of carbon nanotubes into MIL-101 (Fe) and their subsequent calcination for electrochemical detection of nitrite. MOFs-derived α-Fe2O3 polyhedrons are attached on the surface of CNTs tightly, forming hierarchical hybrids with interconnected building blocks. The in-situ insertion of CNTs in the novel hybrids shortens the electron-transfer distance between the α-Fe2O3 and CNTs, which makes α-Fe2O3 become highly active for oxidation of nitrite. The prepared sensor demonstrated excellent performances of nitrite detection with the limit of detection (LOD) as low as 0.15 μM, the high sensitivity of 334 μA mM−1 cm−2 and the wide linear range from 0.5 μM to 4000 μM. What's more, the prepared sensor displayed the prominent reproducibility and superior stability with excellent anti-interference ability, and then was successfully applied for the detection of nitrite in Tap water and Pond water.

Threshold-voltage shift model based on electron tunneling under positive gate bias stress for amorphous InGaZnO thin-film transistors

An analytical threshold-voltage (Vth) shift model of amorphous InGaZnO thin-film transistors (a-IGZO TFTs) under positive gate bias stress (PGBS) is reported in this paper. It is demonstrated that electrons in active layers of a-IGZO TFTs can tunnel into gate insulators when PGBS is applied, and a portion of the tunneled electrons would tunnel back. The transfer distance of the tunneled electrons and the time-dependent electron distribution in gate insulators are analyzed with the back-tunneling effect taken into consideration. Finally the Vth shift under PGBS is predicted and the influences of gate voltage and stress time are discussed. The calculated Vth shift under PGBS shows good consistency with the reported experimental data.

Surface and Interface Engineering in Ag2S@MoS2 Core–Shell Nanowire Heterojunctions for Enhanced Visible Photocatalytic Hydrogen Production

AbstractAn Ag2S@MoS2 core–shell nanowire heterojunction, facilely synthesized by simultaneous sulfuration of Ag nanowires (NMs) and growth of MoS2, is used as a model system to disclose how the surface and interface structures influence the photocatalytic activity. The Ag2S@MoS2 NWs with different loading amounts of MoS2 are used as photocatalysts for H2 production. It is found that the highest photocatalytic activity is realized by a moderate loading amount of MoS2. A lower loading amount of MoS2 not only reduces the interfacial contact for insufficient electron–hole separation but also decreases the number of catalytic active sites for H2 production, while a higher loading amount of MoS2 increases the light‐shielding effect of Ag2S and extends the distance of electron transfer to the catalytic active sites for H2 production. Furthermore, with the same loading amount of MoS2, Ag2S@MoS2 NWs also exhibit superior H2 production activity in comparison with pre‐Ag2S@MoS2 NWs with MoS2 grown on pre‐synthesized Ag2S nanowires. The proposed reason is that the simultaneous sulfuration of Ag nanowires and growth of MoS2 results in an intimate contact between Ag2S and MoS2 for smooth interfacial charge transfer, while the two‐step synthetic method leads to a lower quality of the MoS2‐Ag2S interface and thus poor interelectron transfer. This work highlights the importance of a rational surface and interface design of semiconductor heterojunctions for realizing high‐performance photocatalytic applications.

Thermally stable TiO2 quantum dots embedded in SiO2 foams: Characterization and photocatalytic H2 evolution activity

Highly dispersed and thermally stable TiO2 quantum dots (TiO2-QDs) were achieved in the pore channels of SiO2 foams with large pore size (14–20 nm) via in-situ hydrolysis of Ti-alkoxide. Owing to the anchoring effect between TiO2-QDs and the pore-wall of SiO2 foam, both the TiO2 phase transformation from anatase to rutile and the aggregation of TiO2-QDs were effectively prohibited. The anatase TiO2-QDs anchored on the surface of silica foams could be well maintained with a ultrafine crystal size (<7.0 nm) even after high temperature (up to 1000 °C) calcination in air, suggesting a high thermal stability. The sample of TiO2-QDs/SiO2 photocatalysts (molar ratio of Ti/Si = 60%, 900 °C) still exhibited a high H2 evolution rate (HER, 10399 μmol g−1 h−1) for reducing water with a quantum efficiency of 17.8% under UV light irradiation (λ = 365 nm), slightly lower than that of the sample treated at 500 °C. In the absence of the silica foam, the pure TiO2 crystals calcined at 900 °C crystals nearly cannot exhibit an obvious HER value. Such excellent photocatalytic hydrogen evolution performance was ascribed to the short electron-transfer distance, high anatase crystallinity, uniform dispersity in silica foam, and excellent stability of the TiO2-QDs. This proposed route offered an effective platform for fabricating highly active metal oxide QDs with high thermal stability, greatly prolonging the recyclability.

Triethanolamine-Modified Gold Nanoparticles Synthesized by a One-Pot Method and Their Application in Electrochemiluminescent Immunoassy.

In many electrochemiluminescent (ECL) systems, coreactants play crucial roles in the redox-induced light emission process at the electrode surface. In this work, a novel and environment-friendly nanoplatform for ECL immunosensing enabled by triethanolamine (TEOA)-modified gold nanoparticles (TEOA@AuNPs) is reported. The monodisperse TEOA@AuNPs are fabricated by one-pot synthesis using TEOA as both reducing and stabilizing agent. Then the TEOA@AuNPs-modified electrode not only acted as coreactant for Ru(bpy)32+ ECL system but also provided a carrier for antibody 1 to form label-free immunosensor through an interaction between antigen and antibody. The unique structure of the TEOA@AuNPs loaded a large amount of coreactant of Ru(bpy)32+, which shortened the electron-transfer distance from the AuNPs surface to the appended TEOA molecules, thereby greatly enhancing the ECL efficiency and amplifying the ECL signal. In addition, Ru(bpy)32+-doped silica (RuSiO2) nanoparticles and antibody 2 were combined to form a composite for labels and a sandwich-type ECL immunosensor has been constructed. The possible mechanism of those ECL systems have also been proposed and confirmed by the EC-MS hyphenated technique. The human cardiopathy biomarker, cardiac troponin I (cTnI), was detected in a wide linear concentration range and the limit of detection (LOD) was 34 or 5.5 fg mL-1 by using the proposed label-free or labeling ECL immunoassay method.

The harpooning mechanism as evidenced in the oxidation reaction of the Al atom.

The harpooning mechanism has long been proposed for elementary reaction dynamics involving metals. It is characterized by an initial electron transfer (ET) process from the metal to the oxidant molecule. For the titled reaction Al + O2, the ET distance can be predicted to be 2.6 Å by simply calculating the energy difference between the ionization energy of the Al atom and the electron affinity of the O2 molecule. Hereby we experimentally derived the maximum impact parameter bmax of 2.5 ± 0.2 Å for the titled reaction, in consistency with the predicted ET distance. This derivation of bmax was achieved by using the crossed molecular beam experiment at a collision energy of 507 cm-1 (i.e. 1.45 kcal mol-1) with a high resolution time-sliced ion velocity imaging detection of the state-selective AlO products based on the (1 + 1) resonance-enhanced multiphoton ionization. The small rotational constant of the AlO(X2Σ+) radical (Be = 0.6413 cm-1) facilitated the formation of the AlO(v = 0) products in high rotational levels up to the energetically limited state, Nmax = 52, with an almost zero velocity mapping. Hence, in this extreme angular momentum disposal case, the collisional orbital angular momentum l was nearly completely channeled into the product rotational angular momentum as a consequence of the conservations of energy and angular momentum, offering a reaction system that breaks the restriction of kinematically favored mass combination in order to obtain information on the impact parameters. The present study yields the first direct derivation of bmax from the maximum rotational level of products under the experimental condition with the recoil energy E'T ≈ 0. This, in turn, provides solid evidence in supporting the harpooning mechanism.

Core-shell Fe3O4@Fe ultrafine nanoparticles as advanced anodes for Li-ion batteries

Core-shell Fe3O4@Fe ultrafine nanoparticles (nano-Fe3O4@Fe, Fe3O4 content 84 wt%) with a core (Fe) diameter of 5.1 ± 1.4 nm and a shell (Fe3O4) diameter of 10.9 ± 1.6 nm is prepared by a liquid-phase pyrolysis and partial oxidation method. It is found that the core-shell Fe3O4@Fe ultrafine nanostructure can efficiently improve the electrochemical performance of Fe3O4 as anode material for Li-ion batteries in terms of rate capability and cycle life. For instance, specific capacities of 884 and 705 mAh/g can be obtained for the nano-Fe3O4@Fe electrode after 100 cycles at 200 mA/g and 500 cycles at 1000 mA/g, respectively. It is believed that these improvements can be attributed to the significant shortened transfer distance of electrons and Li-ions with relatively low specific surface area, ultrahigh electronic conductivity inside the nanoparticles and good ductility to accommodate the asymmetric volume change.

Synthesis, characterization and electrochemical properties of different morphological ZnO anchored on graphene oxide sheets

In this study, we reported an optimized facile method to synthesize ZnO particles of three kinds of morphologies, flower-like, rod-like and sphere. Although ZnO grew along the a- and c-axes, however, the anisotropic crystal growth mechanism of ZnO particles was investigated by the ratio of precursor and temperature of the reaction. The characterizations of three ZnO particles were measured by Field-emission scanning electron microscopy, Fourier-transform infrared spectroscopy and X-ray diffraction. In addition, ZnO with three shapes was fixed on gold-printed circuit board to detect their electrochemistry property in a 3% H2O2/phosphate buffer, while ZnO/GO (graphene oxide) composite was obtained by organic linking which showed the different electrochemical results compare to that of ZnO. electron-transfer distance and speed have been changed between the products and support due to the combination of ZnO and GO. The exploration of ZnO of different shape and ZnO/GO composites on their features and properties would provide significant evidence for their application as sensors in extensive fields.

Significance of [2Fe-2S] Cluster N1a for Electron Transfer and Assembly of Escherichia coli Respiratory Complex I.

NADH:ubiquinone oxidoreductase, respiratory complex I, couples electron transfer from NADH to ubiquinone with proton translocation across the membrane. NADH reduces a noncovalently bound FMN, and the electrons are transported further to the quinone reduction site by a 95 Å long chain of seven iron-sulfur (Fe-S) clusters. Binuclear Fe-S cluster N1a is not part of this long chain but is located within electron transfer distance on the opposite site of FMN. The relevance of N1a to the mechanism of complex I is not known. To elucidate its role, we individually substituted the cysteine residues coordinating N1a of Escherichia coli complex I by alanine and serine residues. The mutations led to a significant loss of the NADH oxidase activity of the mutant membranes, while the amount of the complex was only slightly diminished. N1a could not be detected by electron paramagnetic resonance spectroscopy, and unexpectedly, the content of binuclear cluster N1b located on a neighboring subunit was significantly decreased. Because of the lack of N1a and the partial loss of N1b, the variants did not survive detergent extraction from the mutant membranes. Only the C97AE variant retained N1a and was purified by chromatographic steps. The preparation showed a slightly diminished NADH/ferricyanide oxidoreductase activity, while the NADH:decyl-ubiquinone oxidoreductase activity was not affected. N1a of this preparation showed unusual spectroscopic properties indicating a different ligation. We discuss whether N1a is involved in the physiological electron transfer reaction.

Enzymes Confinement in Gold Nanospikes Electrodes Fabricated By Metal-Assisted Chemical Etching for Enhanced Electron Transfer

The field of enzyme based biofuel cells (EBFC) which utilize enzymes that can consume complex fuels (i.e. sucrose, fructose, etc.) and fuel mixtures to produce electrical energy has expanded over the last 3 decades, and it is now possible to consider applications for implantable fuel cells, bio-battery and aquatic device power source. The last three decades have seen major advancements in the field to enhance the open circuit potentials, current and power densities, fuel efficiency and biocatalyst stability. These advances have resulted in open circuit potentials increasing from 175 mV to almost 1 V and current densities increasing from μA/cm2 to mA/cm2. These increases come from enhanced electrochemically assessable surface areas with nanomaterials, increasing the oxidation reaction activity of anodes with enzyme cascades, metabolons, and optimal cell design to minimize internal resistance. However, further researches into improving power density over 1~5 mW are still needed to supply the power for stable operation of target devices. In this situation, the stable power output is hampered by a low level of electron transfer rate since electron transfer is known as crucial factor that determines performance of EBFC systems. The low level of electron transfer rate is resulted from several reasons that are related to protein structure and enzyme-layer formation. In detail, the redox center where electron is generated is often buried inside the protein matrix and moreover, enzymes are randomly oriented or forms multi-layers of enzymes during loaded on electrode, all of which attribute to long distance of electron transfer and degrade the performance of enzymatic electrode as well. To alleviate these problems, many groups have studied to develop the methods to enhance the electron transfer in these circumstances. Especially, construction of nanostructured high surface electrodes has been spotlighted because it could facilitate the electron transfer and thus performance of enzymatic electrode. In this research, we attempted to fabricate the nanostructured bioanode, optimizing the electron transfer from enzymes to electrode by control of enzyme layer thickness on the electrode surface. Genetically expressed FAD-dependent glucose dehydrogenase is immobilized on Au electrode modified by metal assisted chemical etching (MaCE). Recently, the fabrication of silicon (Si) subwavelength structure (SWS) by means of metal-assisted chemical etching (MaCE) has received increasing attention for its several merits during the modification of electrode surface that low-cost, fast, and scalable. Through this methodology, we fabricated nanospikes in pyramidal structure on the electrode surface, in which the nanospikes exist periodically with a sub-wavelength pitch all over the electrode surface. The effect of nanofabrication in this study is that immobilized enzyme on electrode surface are facilitated to be evenly distributed on the electrode surface. The periodically inclined structure grants equal opportunity of enzyme loading for unit area of electrode surface. By achieving the uniform distribution of enzymes, the distance between enzyme redox center and electrode surface can be reduced by excluding enzyme multilayers. Here, we experimentally studied the effect of pyramidal structure on enzymatic behaviors. During the experiment, the silicon (Si) wafer was selected with high conductive type for eliminating the possible overpotential that could be occured from the support material. Ag nanoparticles were used to assist the etching process of Si substrate, providing catalytic sites. The fabrication utilizing various diameter of Ag nanoparticles and etching times were conducted for having electrode candidates with different periodicities and pitch sizes. The optimized structure was confirmed by testing with electrochemical method, cyclic voltammetry (CV), and the optical slope which includes periodicity and pitch size was determined. Based on this research, it was concluded that electrode morphology is parameter that determines the performance of EBFC. Therefore, electrode structure for EBFC should be constructed in consideration of bio-electrode compatibility, not just of high surface area. Figure 1

Spontaneous and Widespread Electricity Generation in Natural Deep-Sea Hydrothermal Fields.

Deep-sea hydrothermal vents discharge abundant reductive energy into oxidative seawater. Herein, we demonstrated that in situ measurements of redox potentials on the surfaces of active hydrothermal mineral deposits were more negative than the surrounding seawater potential, driving electrical current generation. We also demonstrated that negative potentials in the surface of minerals were widespread in the hydrothermal fields, regardless of the proximity to hydrothermal fluid discharges. Lab experiments verified that the negative potential of the mineral surface was induced by a distant electron transfer from the hydrothermal fluid through the metallic and catalytic properties of minerals. These results indicate that electric current is spontaneously and widely generated in natural mineral deposits in deep-sea hydrothermal fields. Our discovery provides important insights into the microbial communities that are supported by extracellular electron transfer and the prebiotic chemical and metabolic evolution of the ocean hydrothermal systems.

Spontaneous and Widespread Electricity Generation in Natural Deep‐Sea Hydrothermal Fields

AbstractDeep‐sea hydrothermal vents discharge abundant reductive energy into oxidative seawater. Herein, we demonstrated that in situ measurements of redox potentials on the surfaces of active hydrothermal mineral deposits were more negative than the surrounding seawater potential, driving electrical current generation. We also demonstrated that negative potentials in the surface of minerals were widespread in the hydrothermal fields, regardless of the proximity to hydrothermal fluid discharges. Lab experiments verified that the negative potential of the mineral surface was induced by a distant electron transfer from the hydrothermal fluid through the metallic and catalytic properties of minerals. These results indicate that electric current is spontaneously and widely generated in natural mineral deposits in deep‐sea hydrothermal fields. Our discovery provides important insights into the microbial communities that are supported by extracellular electron transfer and the prebiotic chemical and metabolic evolution of the ocean hydrothermal systems.

Bimolecular Rate Constants for FAD-Dependent Glucose Dehydrogenase from Aspergillus terreus and Organic Electron Acceptors

The flavin adenine dinucleotide-dependent glucose dehydrogenase (FAD-GDH) from Aspergillus species require suitable redox mediators to transfer electrons from the enzyme to the electrode surface for the application of bioelectrical devices. Although several mediators for FAD-GDH are already in use, they are still far from optimum in view of potential, kinetics, sustainability, and cost-effectiveness. Herein, we investigated the efficiency of various phenothiazines and quinones in the electrochemical oxidation of FAD-GDH from Aspergillus terreus. At pH 7.0, the logarithm of the bimolecular oxidation rate constants appeared to depend on the redox potentials of all the mediators tested. Notably, the rate constant of each molecule for FAD-GDH was approximately 2.5 orders of magnitude higher than that for glucose oxidase from Aspergillus sp. The results suggest that the electron transfer kinetics is mainly determined by the formal potential of the mediator, the driving force of electron transfer, and the electron transfer distance between the redox active site of the mediator and the FAD, affected by the steric or chemical interactions. Higher k2 values were found for ortho-quinones than for para-quinones in the reactions with FAD-GDH and glucose oxidase, which was likely due to less steric hindrance in the active site in the case of the ortho-quinones.

Photoinduced δ electron transfer in phenylene bridged Mo2 dimers.

Photoinduced electron transfer (ET) in Mo2 dimers, [Mo2(DAniF)3]2(μ-E2C(ph)CE2) (DAniF = N,N'-di(p-anisyl)formamidinate, E = O or S), has been studied by femtosecond transient spectral techniques. Using a 355 nm laser pulse, the δ electrons on the Mo-Mo quadruple bonds are selectively excited and subsequent charge separation yields diradicals [Mo2]˙--ph-[Mo2]˙+ and [Mo2]-ph˙--[Mo2]˙+. The charge separation (CS) and recombination (CR) rates are derived by fitting the decay kinetic data of the excited states. Surprisingly, it is found that the CR rate constants (kCR-1, ∼1012 s-1) for [Mo2]˙--ph-[Mo2]˙+ are larger than the data (kCR-2) for [Mo2]-ph˙--[Mo2]˙+ by about one order of magnitude, although in the first case, the ET distance is doubled and the electronic coupling between the donor and acceptor is weaker. Optical analyses reveal that the free energy changes (ΔG°) for the two CR processes correspond to the δ → δ* and the metal (δ) to bridging ligand (π*) transition energies, respectively, and thus, the ET kinetics is dominated likely by the driving force (-ΔG°).

Achievement and assessment of direct electron transfer of glucose oxidase in electrochemical biosensing using carbon nanotubes, graphene, and their nanocomposites

Carbon nanotubes, graphenes, and their hybridized composites with nanoparticles have been attempted to establish a direct electrical communication between the recognition biomolecule and its underlying electrode surface. This review (with 133 refs.) focuses on advances, strategies and technical challenges in the development of reagentless electrochemical biosensors for glucose with enhanced detection sensitivity, selectivity, and simplicity. Specifically, the review commences with a discussion of the relevance of direct electron transfer (DET) in biosensing together with the fundamental of electro-enzymology and kinetics. General aspects of glucose oxidase (GOx), the most popular enzyme with a flavin cofactor, are discussed in view of its historical and important role in the development of electrical biosensors for blood glucose. The next section assesses DET of GOx based on the Marcus theory and the Laviron formalism. The reorganizational energy of the Marcus model and the overpotential play an important role in reaction kinetics and affect the rate of electron transfer significantly. The presence of nanomaterials, particularly for graphene oxide, decreases the electron transfer distance between the enzyme redox center and the underlying electrode surface well beyond 15 A. The improper Marcus-Hush-Chidsey integral is now simplified to estimate the rate of electron transfer with very good accuracy. Critiques, technical challenges, and future possibilities of glucose electrodes with respect to DET are also presented and discussed.

Phase separation induced rhizobia-like Ni nanoparticles and TiO2 nanowires composite arrays for enzyme-free glucose sensor

Accurate detection of blood glucose levels is necessary to prevent diabetic complications which cause disorders of the heart, kidney, retina, and neural system. Hence, we reported a novel non-enzymatic glucose biosensing platform consisting of highly ordered rhizobia-like nickel nanoparticles/titanium oxide nanowires composite arrays (Ni NPs/TiO2 NWAs). The Ni NPs/TiO2 NWAs were fabricated via hydrothermal treatment of Ti foil in a NaOH solution, Ni ion exchange, and subsequent annealing under H2/Ar. The as-reduced Ni NPs were in-situ grown on the surface of TiO2 NWAs by the phase separation of Ni and TiO2. This novel electrode of Ni NPs/TiO2 NWAs exhibits considerable sensitivity of 50.97μAmM−1cm−2 and low detection limit of 0.18μM (S/N=3) as well as a wide linear range from 1μM to 7mM for glucose detection. Moreover, the electrode shows powerful reliability, distinguished stability as well as high selectivity to interfering species such as ascorbic (response about 0.33%) acid and uric acid (less than 1.5%). The promising sensing characteristics Ni NPs/TiO2 NWAs could be contributed to the decreased electron and ion transfer distance of the nano-arrays resulting from the synergetic effect rendered by the highly active Ni NPs and the steady junction between NPs and NWAs. Significantly, this paper offers a consequential guide in fabricating nanocomposites and provides a promising platform for non-enzymatic glucose biosensor.