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WOS: 000405643200003, In this Article, a new electrochemical sensor based on molecular imprinting polymer (MIP) and platinum nanoparticles (Pt NPs)/carbon nitride nanotubes (C3N4 NTs) nanocomposite was developed for atrazine (ATR) analysis. First, the structures of prepared nanocomposites and surfaces were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDX). After the characterization studies, ATR-imprinted glassy carbon electrode (GCE) based on Pt NPs/C3N4 NTs nanocomposite was developed by 100 mM phenol containing 25 nM ATR: The linearity range and the detection limit of the molecular imprinted sensor were calculated as 1.0 X 10(-12)-1.0 X 10(-10) and 1.5 X 10(-13) M, respectively. In addition, the voltammetric sensor was applied to wastewater samples with high recovery.

In this study, a novel electrochemical method as a conductive voltammetric sensor for determination of N-hydroxysuccinimide was developed. The N-hydroxysuccinimide sensor was achieved by carbon paste electrode (CPE) amplified with tri-component nanohybrid composite (Platinum nanoparticle/Polyoxometalate/Two-dimensional hexagonal boron nitride nanosheets) (PtNPs/POM/2D-hBN) and 1-hexyl-3-methylimidazolium chloride (HMICl) as conductive mediators. A significant decrease (110 mV) in the oxidation overvoltage and significant increased (2.4 times) in the current of the N-hydroxysuccinimide were observed using HMICl-PtNPs/POM/2D-hBN/POMBNS/CPE. Furthermore, the HMICl-PtNPs/POM/2D-hBN/POMBNS/CPE exhibited a good linearity from 0.1 to 300 ?M and detection limit 60 nM for determination of N-hydroxysuccinimide. The capability to promote the electron exchange between N-hydroxysuccinimide and the HMICl-PtNPs/POM/2D-hBN/POMBNS/CPE exhibited a novel analytical strategy for fabrication of water pollutant sensor. © 2020 Elsevier B.V., Nanjing Forestry University: 163020139, The authors appreciate Nanjing Forestry University [grant No. 163020139 ] financial support.

A fuel cell is an electrochemical cell that converts a source fuel into an electrical current. It generates electricity inside a cell through reactions between a fuel and an oxidant, triggered in the presence of an electrolyte. Fuel cells have been attracting more and more attention in recent decades due to high-energy demands, fossil fuel depletions, and environmental pollution throughout world. In this study, a facile and cost-effective catalysts have been developed on platinum nanoparticles (PtNPs) supported on nitrogen and sulfur-doped nanomaterial (PtNPs-NS). The successful synthesis of nanomaterials and the prepared glassy carbon electrode (GCE) surfaces were confirmed by transmission electron microscope (TEM), X-ray photo electron spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. According to TEM images, the average particle sizes of PtNPs were found to be approximately 20–25 nm. The effective surface areas of NS/GCE and PtNPs-NS/GCE were calculated to be 105 and 518 cm2/mg, respectively. The PtNPs-NS/GCE also exhibited a higher peak current for methanol oxidation than those of comparable GCE and NS/GCE, providing evidence for its higher electro-catalytic activity. © 2016, Springer Science+Business Media New York.

International audience; The increasing use of platinum in different forms including engineered nanoparticles (PtNPs) in a wide range of industrial applications and in particular in automotive catalysts is leading to a rising concern about their release and fate in the environment. This study investigates for the first time the uptake and fate of PtNPs by plants. Two model organisms Lepidium sativum and Sinapis alba were exposed to 70 nm PtNPs. An enzymatic digestion method was developed in order to extract intact PtNPs from the different plant tissues, optimizing different parameters in order to obtain the highest number of nanoparticles. Single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) was developed to provide information about nanoparticle size, nanoparticle number concentration and the presence of dissolved platinum in the samples. The enzymatic treatment allowed the extraction of PtNPs from the different tissues without changing their oxidation or aggregation state. The presence of PtNPs at the nominal size in all tissues from both plants was observed. PtNPs with higher sizes than the nominal one were observed as well, suggesting the occurrence of an aggregation process. The presence of platinum in the dissolved form was not detected. © The Royal Society of Chemistry 2016.

In the present study, platinum nanoparticles decorated on graphene sheets have been employed as electrocatalysts for both oxygen reduction reaction and hydrogen oxidation reaction in proton exchange membrane fuel cells. A green and simple approach has been followed for the reduction of graphite oxide using l-ascorbic acid (l-ARGO). Platinum nanoparticle decoration on graphene (Pt/l-ARGO) sheets has been carried out by polyol reduction technique. The structural and morphological characterizations have been performed by different characterization techniques to confirm the formation of materials. The power densities have been evaluated from the recorded polarization curves. The single cell measurements show that the electrocatalytic activity of Pt/l-ARGO is superior in comparison to chemically reduced Pt-graphene systems. This journal is � the Partner Organisations 2014.

In this report, a novel molecular imprinted voltammetric sensor based on glassy carbon electrode (GCE) modified with platinum nanoparticles (PtNPs) involved in a polyoxometalate (H 3 PW 12 O 40 , POM) functionalized reduced graphene oxide (rGO) was prepared for the determination of citrinin (CIT). The developed surfaces were characterized by using scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) method. CIT imprinted GCE was prepared via electropolymerization process of 80.0 mM pyrrole as monomer in the presence of phosphate buffer solution (pH 6.0) containing 20.0 mM CIT. The linearity range and the detection limit of the developed method were calculated as 1.0 × 10 -12 -1.0 × 10 -10 M and 2.0 × 10 -13 M, respectively. In addition, the voltammetric sensor was applied to rye samples. The stability and selectivity of the voltammetric sensor were also reported. © 2015 Elsevier B.V. All rights reserved.

A fuel cell is an electrochemical cell that converts a source fuel into an electrical current. It generates electricity inside a cell through reactions between a fuel and an oxidant, triggered in the presence of an electrolyte. Fuel cells have been attracting more and more attention in recent decades due to high-energy demands, fossil fuel depletions, and environmental pollution throughout world. A facile and cost-effective catalysts have been developed on polyoxometalate (NaPWO) functionalized graphene quantum dots (GQDs) with several mono-metallic and bi-metallic nanoparticles such as platinum nanoparticles (PtNPs), palladium nanoparticles (PdNPs) and platinum-palladium nanoparticles (Pt-PdNPs). The successful synthesis of nanomaterials and the prepared glassy carbon electrode (GCE) surfaces were confirmed by transmission electron microscope (TEM), X-ray photo electron spectroscopy (XPS), scanning electron microscope (SEM), electrochemical impedance spectroscopy (EIS) and X-ray diffraction (XRD) method. According to TEM images, the average particle sizes of PtNPs and PdNPs were found to be approximately 20-30 nm. The Pt-PdNPs/NaPWO/GQDs also exhibited a higher peak current for methanol oxidation than those of comparable PdNPs/NaPWO/GQDs and PtNPs/NaPWO/GQDs, thus providing evidence for its higher electro-catalytic activity. © 2016 The Electrochemical Society.

A fuel cell is an electrochemical cell that converts a source fuel into an electrical current. It generates electricity inside a cell through reactions between a fuel and an oxidant, triggered in the presence of an electrolyte. Fuel cells have been attracting more and more attention in recent decades due to high-energy demands, fossil fuel depletions and environmental pollution throughout world. In this study, a facile and cost-effective catalysts have been developed on platinum nanoparticles (PtNPs) supported on nitrogen and sulfur-doped reduced graphene oxide (NSrGO). The successful synthesis of nanomaterials and the prepared glassy carbon electrode (GCE) surfaces were confirmed by transmission electron microscope (TEM), X-ray photo electron spectroscopy (XPS), scanning electron microscope (SEM) and electrochemical impedance spectroscopy (EIS). According to TEM images, the average particle sizes of PtNPs were found to be approximately 15–20 nm. The effective surface areas (ESA) of NSrGO/GCE and PtNPs/NSrGO/GCE were calculated to be 148 and 469 cm2/mg, respectively. The PtNPs/NSrGO/GCE also exhibited a higher peak current for methanol oxidation than those of comparable GCE and NSrGO/GCE, providing evidence for its higher electro-catalytic activity. © 2016, Springer Science+Business Media New York.

Atar, Necip/0000-0001-8779-1412 WOS: 000373096500003 PubMed: 26928060 In this report, a novel molecular imprinted voltammetric sensor based on glassy carbon electrode (GCE) modified with platinum nanoparticles (PtNPs) involved in a polyoxometalate (H3PW12O40, POM) functionalized multi -walled carbon nanotubes (MWCNs) sheets was prepared for the determination of simazine (SIM). The developed surfaces were characterized by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) method. SIM imprinted GCE was prepared via electropolymerization process of 100 mM pyrrole as monomer in the presence of 0.1 M acetate buffer (pH 4.0) containing 25 mM SIM. The linearity range and the detection limit of the developed method were calculated as 1.0 x 10(-19)-5.0 x 10(-9) M and 2.0 x 10(-11) M, respectively. In addition, the voltammetric sensor was applied to wastewater samples. The stability and reproducibility of the voltammetric sensor were also reported. (C) 2016 Elsevier Inc. All rights reserved.

Boron doped graphene (BG) has been prepared using a facile technique and platinum (Pt) nanoparticles has been deposited on BG using different methods like sodium borohydride, polyol and modified polyol reduction method and used as oxygen reduction reaction (ORR) electrocatalyst in hydrogen fuel cell. The identification of crystal phases through X-ray diffraction (XRD) and the dispersion of the electrocatalyst by the Transmission Electronic Microscopy (TEM) have been studied. The electrochemically active surface area has been investigated by Cyclic Voltammetry (CV). The ORR activity has been evaluated by polarization studies using fuel cell fixture. Stability test also conducted in fuel cell mode for 50 h. This study revealed the superior ORR activity and stability of platinum nanoparticles decorated BG, which is synthesized by modified polyol reduction technique. Hence it can be considered as the alternative electrocatalyst for replacing contemporary electrocatalysts. � 2015 Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Nitrogen doped graphene has been synthesized using hydrothermal method and thermal solid state method with ammonia and melamine as nitrogen sources respectively. Platinum nanoparticles have been dispersed over these support materials using polyol method and these Pt loaded nitrogen doped graphene samples have been studied as electrocatalyst for oxygen reduction reaction (ORR) in a proton exchange membrane fuel cell and for methanol oxidation reaction (MOR). Also, the role of multiwalled carbon nanotubes as a spacer which avoids face to face agglomeration of graphene sheets has also been studied for both the samples. The morphology and structure of the graphene based powder samples have been studied using X-ray diffraction, Raman spectroscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. Half cell and full cell measurements have been performed on the samples for ORR and MOR. With the use of functionalized multiwalled carbon nanotubes, a maximum power density of 704 mW cm-2 and 650 mW cm-2 has been obtained with Pt dispersed nitrogen doped graphenes prepared by hydrothermal and thermal solid state methods respectively. The results have been compared with commercial Pt/C catalyst. � 2015 Hydrogen Energy Publications, LLC.

International audience; Nanocomposites combining the mesoporous iron(III) trimesate MIL-100(Fe) (MIL: Matériaux Institut Lavoisier) and platinum nanoparticles (Pt-NPs) have been used as immobilization matrices of glucose oxidase (GOx). Due to the physico-chemical properties of Pt-NPs (electroactivity) and MIL-100(Fe) (high specific surface area and pore volume, biocompatibility), the resulting GOx–MIL-100(Fe)–PtNP bioelectrode exhibits excellent electrocatalytic performances for glucose detection. This novel glucose biosensor presents a high sensitivity of 71 mA M−1 cm−2 under optimum conditions and a low limit of detection of 5 μM with low response time (

An investigation of the frictional behavior of platinum nanoparticles laterally manipulated on graphite has been conducted to answer the question of whether the recent observation of structural superlubricity under ambient conditions [E. Cihan, S. Ipek, E. Durgun, and M. Z. Baykara, Nat. Commun. 7, 12055 (2016)] is exclusively limited to the gold-graphite interface. Platinum nanoparticles have been prepared by e-beam evaporation of a thin film of platinum on graphite, followed by post-deposition annealing. Morphological and structural characterization of the nanoparticles has been performed via scanning electron microscopy and transmission electron microscopy, revealing a crystalline structure with no evidence of oxidation under ambient conditions. Lateral manipulation experiments have been performed via atomic force microscopy under ambient conditions, whereby results indicate the occurrence of structural superlubricity at mesoscopic interfaces of 4000-75 000 nm2, with a noticeably higher magnitude of friction forces when compared with gold nanoparticles of similar contact areas situated on graphite. Ab initio simulations of sliding involving platinum and gold slabs on graphite confirm the experimental observations, whereby the higher magnitude of friction forces is attributed to stronger energy barriers encountered by platinum atoms sliding on graphite, when compared with gold. On the other hand, as predicted by theory, the scaling power between friction force and contact size is found to be independent of the chemical identity of the sliding atoms, but to be determined by the geometric qualities of the interface, as characterized by an average "sharpness score" assigned to the nanoparticles.

Platinum nanoparticles ( d Pt = 1.0–1.2 nm) supported on single CeO 2 and La 2 O 3 metal oxides and Ce 0.8 La 0.2 O 2− δ solid solution were prepared to investigate for the first time the effect of La 3+ -doping of ceria on important mechanistic and kinetic aspects of the water-gas shift (WGS) reaction, namely: (i) the concentration and chemical structure of active adsorbed reaction intermediates present in the C-path and H-path of WGS at 250 and 300 °C, (ii) the chemical nature of inactive species formed during WGS, and (iii) the prevailing mechanistic path among “redox” and “associative” both proposed in the literature. For this, steady-state isotopic transient kinetic analysis (SSITKA) experiments coupled with in situ DRIFTS and mass spectrometry were performed to follow the H-path (use of D 2 O) and C-path (use of 13 CO) of the WGS. In addition, other transient isotopic experiments using operando methodology (use of DRFTS and mass spectrometry) were designed to follow with time on stream the reactivity toward water of the various adsorbed species formed under WGS. It is proposed that on Pt/Ce 1− x La x O 2− δ ( x = 0.0, 0.2 and 1.0) the WGS reaction follows both the “redox” and “associative” mechanisms but the extent of participation of each mechanism to the overall WGS reaction rate depends on the support chemical composition. The WGS kinetic rate (μmol CO g −1 s −1 ) increased by a factor of 2.0 and 2.8 at 300 °C on 0.5 wt% Pt supported on Ce 0.8 La 0.2 O 2− δ compared to CeO 2 and La 2 O 3 , respectively. This was explained by (i) the larger concentration of active surface intermediates formed around each Pt nanoparticle (larger extent of reactive zone) and (ii) the higher reactivity of sites ( k , s −1 ) responsible for CO 2 and H 2 formation on Pt/Ce 0.8 La 0.2 O 2− δ compared to Pt/CeO 2 and Pt/La 2 O 3 . Active OH groups is suggested to be formed on defect sites (Ce 3+ □ s ) of Ce 0.8 La 0.2 O 2− δ as a consequence of the introduction of La 3+ into the ceria lattice, the latter enhancing the concentration of labile oxygen and its surface mobility, important characteristics of the “redox” mechanism.