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SnS is an important semiconductor and its performance depends greatly on its morphology and 3D architecture. So the synthesis for it with specific structures has been widely paid attention. Herein, a novel hollow nanoparticle-based SnS crystal product with microcluster-like 3D network hierarchitectures was developed, via a template-assisted solvothermal route in diethylene glycol (DEG) solvent, followed by annealing in N 2 atmosphere and subsequent corrosion of template by dilute acid. CaCO 3 nanoparticles were used as the template, SnCl 2 as the tin source, thiourea and l -cysteine hydrochloride monohydrate (Cys) as two different sulfur sources for a comparison study. Results show that successful fabrication of the hollow-structured SnS product mentioned above was achieved only in the case of using Cys as the sulfur source, mainly due to much stronger adhesion of Cys on CaCO 3 template and microcluster-like stacking patterns of CaCO 3 nanoparticles in DEG solvent. This novel 3D hierarchical SnS product owns 1–5 times higher specific surface area, unique hollow nanostructure units with rich mesopores inside the shells, and scattering-enhanced absorption in UV–vis light region, as against those previously reported micro-scale tin sulfide 3D hierarchitectures assembled by nanopetals, nanosheets, nanorods, nanobelts, etc. So it should have much more extensive and promising applications. [ABSTRACT FROM AUTHOR]

Abstract: A composite coating which could control drug release and biocorrosion of magnesium alloy stent materials WE42 was prepared. This composite coating was fabricated on the surface of the micro-arc oxidation (MAO) film of the magnesium alloy, WE42, by mixing different degrees of cross-linked gelatin with well-dispersed poly(dl-lactide-co-glycolide) (PLGA) nanoparticles. The PLGA nanoparticles were prepared by emulsion solvent evaporation/extraction technique. Nano ZS laser diffraction particle size analyzer detected that the size of the nanoparticles to be 150–300nm. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) was used to analyze the morphology of the nanoparticles and the composite coating. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) were used to evaluate the corrosion behavior of the composite coating. Drug release was determined by ultraviolet–visible (UV–vis) spectrophotometer. The corrosion resistance of the composite coating was improved by preventing the corrosive ions from diffusing to the MAO films. The drug release rate of paclitaxel (PTX) exhibited a nearly linear sustained-release profile with no significant burst releases. [Copyright &y& Elsevier]

Abstract: Catalytic dechlorination of para-nitrochlorobenzene (p-NCB) by Ni/Fe (nickel/iron) bimetallic nanoparticles was carried out. The catalytic reduction and dechlorination reaction was believed to take place on the surface site of the nanoscale catalysts. In the reaction, Ni plays a role of catalyst decreasing activation energy of hydrogenolysis of C–Cl bonds and the Fe was corroded to produce hydrogen gas. 100% dechlorination efficiency was achieved for particles with 2.0% Ni, in contrast, just 51% chlorine was obtained for particles with 0.5% Ni at the Ni/Fe nanoparticles mass concentration of 6 g l−1 used after 300 min reaction. The p-NCB was first adsorbed by nanoparticles completely then quickly reduced to p-chloroaniline (p-CAN) and aniline (AN), and p-CAN was detected as an intermediate. As expected, with the Ni/Fe addition and the Ni loading percentage over Fe increasing, the temperature going up, and the pH decreasing, the dechlorination efficiency increased. The Ni/Fe catalytic reductants showed prominent activity to the reductive catalytic dechlorination of p-NCB at ambient temperature and pressure as well as high removal efficiency of p-NCB and p-CAN in agricultural pesticide wastewater, therefore, they could be good choices for remediation of contaminated groundwater. [Copyright &y& Elsevier]

Graphical abstract Highlights • Enhanced 2,4-DCBA dechlorination with low intermediate products was achieved. • 2,4-DCBA removal by moveable Pd/AC was 5–194 folds faster than fixed catalysts. • High Pd loading, current, and acidity favored the dechlorination of 2,4-DCBA. • Excessive electrolyte inhibited the dechlorination of 2,4-DCBA. • Good longevity and recyclability of moveable Pd/AC catalyst was confirmed. Abstract In this study, a novel approach was developed for the dechlorination of 2,4-dichlorobenzoic acid (2,4-DCBA) via the combination of the moveable activated carbon (AC) supported palladium (Pd) nanoparticles and nickel (Ni) foam electrode. The morphology and chemical structure of Pd/AC catalyst was investigated by various characterization techniques, including SEM, TEM, EXS-mapping, XRD, and XPS. Pd nanoparticles was successfully loaded and dispersed on the AC, accompanied with the significantly enhanced reactivity. The removal rate of 2,4-DCBA by Ni electrode with moveable Pd/AC catalyst was 222, 25, and 5 folds higher than dispersed AC and Ni electrode system, chemical deposited Pd/Ni electrode, and electrodeposited Pd/Ni electrode, respectively. Compared with the conventional electrocatalytic reductive approach which deposited Pd on the Ni foam electrode, moveable Pd/AC catalyst possesses higher surface area, more atomic H∗ production and more active sites, favored mass transfer, and enhanced reactivity, without the consideration of catalyst loss and deactivation. The effects of Pd:AC mass ratio, constant current, initial solution pH, and electrolyte concentration on the dechlorination of 2,4-DCBA were studied. Generally, high Pd loading, constant current, and acidity favored the dechlorination of 2,4-DCBA, while excessive electrolyte would inhibit the dechlorination of 2,4-DCBA. Good longevity and recyclability of moveable Pd/AC catalyst was confirmed via consecutive experiments. The findings of the present study show that making the catalyst moveable is a promising strategy for electrocatalytic remediation technology. [ABSTRACT FROM AUTHOR]

Stabilized iron sulfide (FeS) nanoparticles have been proven effective in the adsorption of Hg from the water environment. However, previous work with these nanoparticles determined that the separation from the treated water was difficult and time-consuming. In this study, nanoscale FeS-Fe 3 O 4 nanocomposites were firstly synthesized with chitosan as the stabilizer (CTO-MFeS). Then, the Hg adsorption capacity and mechanism were studied. Results showed that the size of the prepared nanoparticles was about 20 nm and the specific surface area was 21.3 m 2 /g. Hg removal by the CTO-MFeS nanoparticles involved both adsorption and precipitation. Further investigation with XPS showed that Hg 2 + was adsorbed on the surface of the CTO-MFeS nanoparticles and reacted with CTO-MFeS to form HgS and [Fe (1 − x) Hg x ]S. It was also found as pH decreased below 4, the adsorption capacity of CTO-MFeS was significantly reduced that might be due to the dissolving of Fe. Additionally, the presence of Cl − resulted in the transformation of Hg 2 + to HgClx 2-x (x = 1, 2, 3, 4) that competed with OH in solution for Hg 2 + and therefore inhibited the adsorption of Hg. Our findings provide additional information that may be useful for a theoretical basis for Hg treatment in water environment. [ABSTRACT FROM AUTHOR]

Iron sulfide (FeS) nanoparticles were known for their excellent ability to scavenge aqueous Hg(II). However, the aggregation and oxidizability of FeS nanoparticles greatly restricted their practical application. This study developed an Al 2 O 3 -supported nanoscale FeS (FeS/Al 2 O 3 ) which effectively optimized the material performance. Characteristic data suggested that FeS/Al 2 O 3 (mass ratio of FeS to FeS/Al 2 O 3 is 30%) with a large specific surface area (142.7 m 2 g −1 ) could evenly distribute FeS, suppressing the aggregation of FeS successfully. The maximum enrichment capacity of Hg(II) on FeS/Al 2 O 3 achieved ∼313 mg/g at pH 6 and 30 °C. The pH studies indicated that alkaline environment strongly inhibited mercury uptake, while removal rate of 1 mg/L Hg(II) maintained a high level (>97.5%) over the pH range of 3–9. However, FeS/Al 2 O 3 loss was observed at low pH due to the acid corrosion. Additionally, the rates of Hg(II) reduction were almost unaffected over the range of 0.1–100 mM NaCl, but greatly inhibited by the presence of humid acid (HA). The synthetic FeS/Al 2 O 3 remained high mercury removal efficiency (over 95% in 1 mg/L Hg(II)) and low iron dissolution rate when preserved for 30 days, showing good long-term stability and remarkable application potential. [ABSTRACT FROM AUTHOR]

Multilayer Zn-doped SnO 2 nanospheres are successfully synthesized by using Sn/Zn bimetal-organic nanoparticles as precursor. These multilayer spheres are found to be very suitable for solving the critical volume expansion problem and mass transfer property due to its high surface area, small crystal size and hollow structure, which is critical for high capacity metal oxide electrodes for lithium-ion batteries. Moreover, the covalently interconnected three-dimensional graphene foams encapsulated these multilayer spheres are successfully obtained through self-assembly effect and chemical cross-linking of graphene oxide nanosheets. The graphene network could further greatly improve the cycling stability and rate capability of the Zn-doped SnO 2 spheres electrode due to its flexible buffering matrix and high electric conduction. As a result, the graphene encapsulating multilayer Zn-doped SnO 2 spheres anodes exhibit excellent rate capacity and a high reversible capacity of 446 mA h g −1 even after 1000 cycles at the current density of 1 A g −1 . These excellent electrochemical performances are ascribed to its large specific surface area, fast electron/ion transfer, and stable electrode structure. Furthermore, this strategy using covalently interconnected 3D graphene foams encapsulate the Zn-doped SnO 2 spheres not only develops a high performance anode material with long cycle life but also holds great promise for binder-free lithium ion batteries. [ABSTRACT FROM AUTHOR]

In order to discuss the effect of polymer coating layer on the Sn anode, the composition and morphology of the solid electrolyte interphase (SEI) film on the surface of Sn and Sn@PEO anode materials have been investigated. Compared with the bare cycled Sn electrode, the SEI on the surface of cycled Sn@PEO electrode is thinner, smoother, and more stable. Therefore, the Sn@PEO nanoparticles can basically keep the original appearance during cycling. Based on the results obtained from X-ray photoelectron spectroscopy (XPS), the SEI formed on the Sn@PEO electrode is characterized by inorganic components (LiCO)-rich outer layer and organic components-rich inner which could make the SEI more stable and inhibit the electrolyte immerging into the active materials. In particular, the elastic ion-conductive polyethylene oxide (PEO) coating could increase the toughness of SEI and allow the SEI to endure the stress variation in repetitive lithium insertion and extraction process. As a result, the Sn@PEO electrodes show significantly better capacity retention than bare Sn electrodes. The findings can serve as the theoretical foundation for the design of lithium-ion battery electrode with high energy density and long cycle life. [ABSTRACT FROM AUTHOR]

Highlights: [•] Nano-Ni/Fe were synthesized in the presence of ultrasonic irradiation. [•] Ultrasonic irradiation can improve nano-Ni/Fe′ disparity and avoid agglomeration. [•] 2,4-DCP was first adsorbed by nano-Ni/Fe, then was quickly dechlorinated. [•] Factors of reductive dechlorination by nano-Ni/Fe were studied. [ABSTRACT FROM AUTHOR]

Nanostructured hollow Sn-Cu multi-phase composite nanoparticles anode that contains Sn and CuSn was synthesized via galvanic replacement reaction using Sn nanoparticles as a sacrificial template. The sacrificial oxidation of Sn and simultaneous reduction of Cu on the surface because of the redox potential difference is proposed to account for the formation of hollow Sn-Cu nanostructures. The structural evolution of the Sn-Cu hollow nanoparticle, in the process of galvanic replacement and structure, composition changes during charge/discharge processes were studied based on scanning electron microscope, X-ray powder diffraction, transmission electron microscopy, and energy dispersive X-ray spectroscopy investigations. The electrochemical properties of the samples were evaluated by galvanostatic discharge-charge cycling, cyclic voltammetry, and electrochemical impedance spectroscopy. Compared with solid Sn-Cu nanoparticles, hollow Sn-Cu nanoparticles showed better capacity retention. The improved electrochemical performance may be attributed to the stable hollow structure and the combination of CuSn. The facile solution-based process and excellent cycling stability show great potential of the multi-phase Sn-Cu hollow composite nanoparticles as an anode material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: Palladium/Iron (Pd/Fe) nanoparticles were prepared by using ultrasound strengthened liquid phase reductive method to enhance dispersion and avoid agglomeration. The dechlorination of 2,4-dichlorophenol (2,4-DCP) by Pd/Fe nanoparticles was investigated to understand its feasibility for an in situ remediation of contaminated groundwater. Results showed that 2,4-DCP was first adsorbed by Pd/Fe nanoparticles, then quickly reduced to o-chlorophenol (o-CP), p-chlorophenol (p-CP), and finally to phenol (P). The induction of ultrasound during the preparation of Pd/Fe nanoparticles further enhanced the removal efficiency of 2,4-DCP, as a result, the phenol production rates increased from 65% (in the absence of ultrasonic irradiation) to 91% (in the presence of ultrasonic irradiation) within 2h. Our data suggested that the dechlorination rate was dependent on various factors including Pd loading percentage over Fe0, Pd/Fe nanoparticles availability, temperature, mechanical stirring speed, and initial pH values. Up to 99.2% of 2,4-DCP was removed after 300min reaction with these conditions: Pd loading percentage over Fe0 0.3wt.%, initial 2,4-DCP concentration 20mgL−1, Pd/Fe dosage 3gL−1, initial pH value 3.0, and reaction temperature 25°C. The degradation of 2,4-DCP followed pseudo-first-order kinetics reaction and the apparent pseudo-first-order kinetics constant was 0.0468min−1. [Copyright &y& Elsevier]

Abstract: In this study a systematic investigation of two specified MWCNTs-Pd/Fe nanocomposites to remove 2,4-dichlorophenol (2,4-DCP) is presented. Two specified Multi-Walled Carbon Nanotubes (MWCNTs), i.e., 60–100nm and 10–20nm were introduced in nZVI synthesis in order to improve its adsorption–dechlorination efficiency. Both MWCNTs-Pd/Fe nanocomposites showed excellent adsorption efficiencies for phenols and followed the sequential order; 2,4-DCP>p-CP>o-CP>P. Batch sorption experiments including kinetics and isotherm were also intensively investigated. Significantly high 2,4-DCP removal was observed after 1min when it reached to 49.7% and 53.2%, then continuously increased up to 95.2% and 77.7% after 5h at 0.20wt.% Pd loading by 60–100nm and 10–20nm MWCNTs-Pd/Fe nanocomposites, respectively. However, stronger dechlorination and weaker adsorption was found in 60–100nm MWCNTs-Pd/Fe nanocomposites. Moreover, an integrated approach of physical adsorption by 60–100nm MWCNTs and chemical reduction by Pd/Fe nanoparticles to remove 2,4-DCP was successfully achieved. The property of quick adsorption of targeted pollutants and steady release of dechlorination products enhance the applicability of this process for an in situ pollution remediation measures. [Copyright &y& Elsevier]

Abstract: This paper describes the synthesis of sodium carboxymethyl cellulose (CMC)-stabilized Pd/Fe nanoparticles and their applications to the dechlorination of 2,4-dichlorophenoxyacetic acid (2,4-D) under controlled laboratorial conditions. For this purpose batch mode experiments were conducted to understand the effects of CMC on the surface characteristics of Pd/Fe nanoparticles, optimum removal of 2,4-D and other surface interactions mechanism. Our experimental results demonstrated considerable enhancements in particle stability and chemical reactivity with the addition of CMC to Pd/Fe nanoparticles. Transmission electron microscopy (TEM) analysis indicated that CMC-stabilized Pd/Fe nanoparticles were well dispersed, and nanoparticles remained in suspension for days compared to non-stabilized Pd/Fe nanoparticles precipitated within minutes. The isoelectric point (IEP) of the nanoparticles shifted from pH 6.5 to 2.5, suggesting that CMC-stabilized Pd/Fe nanoparticles were negatively charged over a wider pH range. Our batch experiments demonstrated that CMC-stabilized Pd/Fe nanoparticles (0.6gFeL−1) were able to remove much higher levels of 2,4-D with only one intermediate 2-chlorophenoxyacetic acid (2-CPA) and the final organic product phenoxyacetic acid (PA), than non-stabilized Pd/Fe nanoparticles or microsized Pd/Fe particles. The removal percentage of 2,4-D increased from 10% to nearly 100% as the reaction pH decreased from 11.5 to 2.5. The optimal CMC/Fe mass ratio for the dechlorination of 2,4-D was determined to be 5/1, and the removal of 2,4-D was evidently hindered by an overdose of CMC. [Copyright &y& Elsevier]

Abstract: The present study dealt with the performance evaluation of the nanoscale Fe0 systems for the remediation of chromium contaminated groundwater in the ambient environment. The role of humic acid (HA) in the Cr(VI) removal and the reduction mechanism were investigated. HA was found to exert an obvious inhibitory effect on Cr(VI) removal by Fe0 nanoparticles, and the Cr(VI) removal efficiencies decreased from 71.6%, 58.4%, 57.8% to 38.5% with the increasing HA concentrations (0, 5, 10, 20 to 40mgL−1). A dual effect of humic acid on chromium(VI) reduction by Fe0 nanoparticles was observed. HA adsorbed on the surface of Fe0 nanoparticles and occupied the active surface sites, leading to the decrease in Cr(VI) reduction rates. Greater was the adsorbed HA, the more obvious was the inhibitory effect. However, the HA adsorption on iron surface areas was one of the factors leading to the decreased reduction rate. The appropriate starch dosage (0.5g per 0.3g nanoscale Fe0 particles) could definitely eliminate the inhibitory effect of humic acid. [Copyright &y& Elsevier]

Abstract: The photocatalytic degradation of 2-chlorophenol (2-CP) irradiated with visible light over iodine doped TiO2 (IT) modified with SnO2 (SIT) nanoparticles has been investigated in this study. The structure and optical properties of the SIT catalysts have been well characterized by X-ray diffraction, the Brunauer–Emmett–Teller method, transmission electron microscopy, UV–visible absorption spectra and X-ray photoelectron spectroscopy. The effects of preparation conditions, such as SnO2 content and calcination temperature, on the photocatalytic degradation efficiency have been surveyed in detail. The improved photocatalytic activity of SIT is derived from the synergistic effect between the SnO2 and IT, which promoted the efficiency of migration of the photogenerated carriers at the interface of the catalysts and thereby enhanced the efficiency of photon harvesting in the visible region. The action of scavengers (fluoride ion, iodide ion, tert-butyl alcohol, and persulfate ion), as well as N2 purging on the photodegradation rate reveal that the valence band hole is mainly responsible for the effective photocatalytic removal of 2-CP and the corresponding TOC reduction. [Copyright &y& Elsevier]

Abstract: Pd/Fe bimetallic nanoparticles were synthesized for treatment of 2,4-dichlorophenol (2,4-DCP) in the presence of humic acid (HA), in order to understand their applicability for in situ remediation of groundwater. In this case, 2,4-DCP was catalytically dechlorinated to form the final products – phenol (P) via two intermediates, namely o-chlorophenol (o-CP) and p-chlorophenol (p-CP). We demonstrated that the carbon mass balances during the dechlorination were in the range of 82–91%, and other carbons were absorbed on the surface of Pd/Fe bimetallic nanoparticles. Our results suggest the dechlorination reaction of 2,4-DCP by Pd/Fe bimetallic nanoparticles in the presence of HA followed pseudo-first-order kinetics. HA competed for reaction sites on the Pd/Fe bimetallic nanoparticles with 2,4-DCP, and thus reduced the efficiency and rate of the dechlorination of 2,4-DCP. Efficiencies of dechlorination and phenol formations increased significantly as the Pd content increased from 0.10wt.%, 0.15wt.% to 0.20wt.%, the removal percentage of 2,4-DCP increased from 70.4%, 98.4% to 99.4% within 300min, respectively, the nitrate (NO3 −) content in water also has a significant impact on 2,4-DCP dechlorination efficiency. Our results show that no other intermediates were generated besides Cl−, o-CP, p-CP and phenol during the catalytic dechlorination of 2,4-DCP. [ABSTRACT FROM AUTHOR]

Abstract: The reduction of hexavalent chromium or Cr(VI) by zero-valent iron (Fe0) nanoparticles has received increasing attention in recent years. However, Fe0 nanoparticles prepared using conventional methods suffered several drawbacks due to their high reactivity towards surrounding media, which led to the formation of much larger flocs and significant loss in reactivity. To overcome these problems, we synthesized Fe0 nanoparticles by applying water-soluble carboxymethyl cellulose (CMC) as a stabilizer. CMC-stabilized Fe0 nanoparticles displayed much less agglomeration but greater Cr(VI) reduced power than those prepared without a stabilizer. At a dose of 0.15g L− 1, CMC-stabilized Fe0 nanoparticles were able to reduce 100% of 10mg L− 1 Cr(VI) in minutes. Several factors that may affect the efficiency of Cr(VI) removal were investigated. These included the concentration of CMC, the concentration of Fe0 nanoparticles, the initial Cr(VI) concentration, the pH value, the reaction temperature and the concentration of the calcium cation in the reaction mixture. Our study suggested that the introduction of an innocuous stabilizer such as CMC could significantly improve the performance of Fe0 nanoparticles for environmental remediation applications. [Copyright &y& Elsevier]

Abstract: This paper describes the use of highly reactive magnetite (Fe3O4) nanoparticles-stabilized Fe0 nanocomposites for the reduction and mitigation of hexavalent chromium Cr(VI) species in aqueous solutions. Higher proportions of Fe3O4 in the nanocomposites could increase the rate of Cr(VI) reduction. In the absence of magnetite, the Cr(VI) mitigation rate was just 51.4% after 60min of reaction, while with an initial Fe3O4 mass loading of 3gl−1, the Cr(VI) mitigation rate was nearly 100% after 60min. The optimal ratio of Fe3O4:Fe0 for the mitigation of Cr(VI) was found to be 40:1. Otherwise, solution pHs significantly affected the rate of Cr(VI) reduction, with reactions occurring more rapidly under acidic or neutral than basic conditions. It is hypothesized that the high efficiency of the Fe3O4 nanoparticles-stabilized Fe0 nanocomposites for Cr(VI) reduction was a direct result of the attachment of Fe0 nanoparticles to the surface of magnetite, which prevents the aggregation of nano-Fe0, moreover, the electron transfer during the reduction process most likely takes place via Fe0 nanoparticles that are located at the magnetite octahedral sites, which are versatile redox centers as they can accommodate both Fe(III) and Fe(II), and this will promote the reduction of Cr(VI). Cr(VI) reduction is coupled with nano-Fe0 oxidation. Nano-Fe0 particles are located at the magnetite octahedral sites. Ions of Fe(II) and Fe(III) accommodated by magnetite octahedral sites are products of nano-Fe0 oxidation. Therefore, Cr(VI) reduction is mediated either by nano-Fe0 (direct reduction) or Fe(II) species (indirect reduction). Additionally, catalytic Cr(VI) reduction by molecular H2 (or atomic H) is possible. [Copyright &y& Elsevier]

The dechlorination of 2,4-dichlorophenol (2,4-DCP) by Ni–Fe nanoparticles in the presence of humic acid (HA) was investigated to understand the feasibility of using Ni–Fe for the in situ remediation of contaminated groundwater. 2,4-DCP was first adsorbed by Ni–Fe nanoparticles, then quickly reduced to o-chlorophenol (o-CP), p-chlorophenol (p-CP), and finally to phenol (P). However, the introduction of HA decreased the removal percentage of 2,4-DCP, as a result, the phenol production rates dropped from 86% (in the absence of HA) to 29% within 2h. Our data suggested that the dechlorination rate was dependent on a number of factors including Ni–Fe availability, Ni loading percentage over Fe, temperature, pH, and HA concentration. In particular, the removal percentage of 2,4-DCP was determined to be 100, 99, 95, 84 and 69%, for HA concentrations of 0, 5, 10, 30 and 40mgL−1, respectively. The kinetic calculations for the dechlorination of 2,4-DCP indicated that k values for 2,4-DCP dechlorination dropped from 0.14, 0.051, 0.039, 0.021 to 0.011min−1 with increasing concentrations of HA from 0, 5, 10, 30 to 40mgL−1. [Copyright &y& Elsevier]

• The ZnO-rGO composites electrode was fabricated by self-assembly. • The agglomeration of nanoparticles and GO sheets was inhibited by self-assembly. • The sensitivity of this electrode to dopamine has been extremely improved. • This electrode has good reproducibility and anti-interference ability. This study introduces the self-assembly method to fabricate Zinc Oxide (ZnO) decorated reduced Graphene Oxide (ZnO-rGO) composites with higher sensitive for detection of dopamine (DA), one of the most common biomarkers of Parkinson's disease. The approach is reported to self-assembly Graphene Oxide (GO) and ZnO nanoparticles (NPs) modified by 3-aminopropyl triethoxysilane (APTES), forming ZnO-GO composites, then ZnO-rGO composites were obtained by electrochemical reduction of ZnO-GO composites. Utilizing differential pulse voltammetry (DPV), we found ZnO-rGO composites fabricated by the method of self-assembly reduced the agglomeration of ZnO and GO and showed a higher sensitivity for detection of DA than the dopamine electrochemical sensor previously reported. The fabricated sensor showed a linear dynamic range on 5–70 μM with a LOD of 0.167 μM (S/N = 3) and a sensitivity of 458nA/μM in response to DA. Finally, the as-prepared ZnO-rGO composite displayed an excellent detection recovery of 98.8 ~ 101.2% in human serum. [ABSTRACT FROM AUTHOR]