ACS Applied Nano Materials
·
2018
·
IF 0
Guohong Ren,Yajun Liu,Weigang Wang,Mingqian Wang,Zhicheng Zhang,Ying Liang,Shishan Wu,Jian Shen
Exploitation of highly active catalysts for alcohol electrooxidation is urgent for direct alcohol fuel cells (DAFCs). In this research, a facile and mild synthetic approach is utilized to control and tailor the morphology of the three-dimensional (3D) urchin-like Pd@PtNi nanostructures (NSs), and the formation mechanism of the as-prepared nanostructures is expounded in detail. The Pd@PtNi NSs exhibit outstanding electrochemical properties and remarkable durability toward both methanol and ethanol oxidation reaction (MOR and EOR) in alkaline solution. The electrochemically active surface area (ECSA) of the Pd@PtNi NSs is 59.5 m2 g–1, and their mass activities for MOR and EOR are 1614.3 and 1502.3 mA mg–1, respectively, which are much higher than those of their ternary or binary alloy counterparts as well as commercial Pt black catalysts. Moreover, it still retains high current densities after catalyzing 10 000 s, while the current densities of other nanocatalysts reduce to nearly zero. The outstanding electrochemical activities and durability are owing to the specific 3D urchin-like nanostructures providing enormous active sites for catalytic reaction and the synergy effects between Pt, Pd, and Ni atoms. The 3D urchin-like Pd@PtNi NSs will enrich the electrocatalysts for DAFCs.
✓ 已验证
产品关联
DOI
RSC Advances
·
2018
·Vol. 8
·期 69
·39291-39295
·
IF 2.936
Weiming Wu,Xiao-Yuan Wu,Sa-Sa Wang,Can-Zhong Lu
Nanocrystalline transition metal phosphides (CoP and Ni2P) were successfully synthesized by a simple calcination method by using transition metal hydroxides and NaH2PO2 as raw materials. Their catalytic activities for the hydrogen evolution from water electrolysis were evaluated with silicotungstic acid as an electron-coupled-proton buffer, whereby hydrogen and oxygen could be produced separately. It was found that the CoP sample showed higher catalytic activity (32 mmol min−1 g−1) and good stability (12 h) as compared to the Ni2P sample, and its catalytic activity could rival that of the commercial Pt/C catalyst. The electrochemical results revealed that CoP had high cathodic current and small charge transfer resistance, which further suggested it was indeed an efficient noble metal-free catalyst for hydrogen evolution from water electrolysis.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2018
·
IF 4.229
Sheng Zhu,Pengcheng Li,Guitai Wu,Zhenyu Li,Pei Wu,Yongming Hu,Haoshuang Gu,Wanping Chen
Two kinds of Pt SnO 2 composite nanoceramics have been prepared using SnO 2 nanoparticles and SnO 2 agglomerate powder separately. One is of a relatively uniform and porous microstructure with a specific surface area of 8.1 m 2 /g, and the other is of a rather non-uniform microstructure with large SnO 2 agglomerates and crack-like pores and a specific surface area of 6.4 m 2 /g. While the samples of uniform microstructure typically show a sensitivity of 150 to 1% H 2 – 20% O 2 – N 2 in air of 50% relative humidity (RH) at room temperature , those of non-uniform microstructure surprisingly show much higher sensitivities of 850 and 450 in air of 50% and 70% RH, respectively, to the same concentration of hydrogen. The influence of humidity on the samples has been further studied and a much higher humidity tolerance has been revealed for those samples of non-uniform microstructure. All these results demonstrate a clear and unexpected advantage of a non-uniform microstructure over a uniform one in humidity tolerance for room-temperature hydrogen-sensitive Pt SnO 2 composite nanoceramics.
✓ 已验证
产品关联
DOI
高影响因子
ChemSusChem
·
2018
·Vol. 11
·期 14
·2382-2387
·
IF 7.411
Zhongjian Li,Gang Li,Xinlu Chen,Zheng Xia,Jiani Yao,Bin Yang,Lecheng Lei,Yang Hou
Graphical Confining metal inside carbon : Ni nanoparticles are embedded into N-doped carbon nanotubes (Ni@N-C) by rational catalyst design. The Ni@N-C catalyst exhibits high catalytic activity and good biocompatibility, which is further coupled with Cupriavidus necator H16 in a water splitting–biosynthetic system to achieve efficient conversion of CO 2 to poly-β-hydroxybutyrate. CO 2 reduction has drawn increasing attention owing to the concern of global warming. Water splitting–biosynthetic hybrid systems are novel and efficient approaches for CO 2 conversion. Intimate coupling of electrocatalysts and biosynthesis requires the catalysts possess both high catalytic performance and excellent biocompatibility, which is a bottleneck of developing such catalysts. Here, a complex of Ni nanoparticles embedded in N-doped carbon nanotubes (Ni@N-C) is synthesized as a hydrogen evolution reaction electrocatalyst and is coupled with a hydrogen oxidizing autotroph, Cupriavidus necator H16, to convert CO 2 to poly-β-hydroxybutyrate. In Ni@N-C, the Ni nanoparticles are encapsulated in N-C nanotubes, which prevents bacteria from direct contact with Ni and inhibits Ni 2+ leaching. As a result, Ni@N-C exhibits excellent biocompatibility and stability. This work demonstrates that electrocatalysts and biosynthesis can be intimately coupled through rational catalyst design.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2018
·
IF 8.173
Li Ma,Liya Zhou,Ying He,Lihui Wang,Zhihong Huang,Yanjun Jiang,Jing Gao
Core-shell structured nanocomposites (named PtPd@NCS) with N-doped carbon shell and bimetal core (Pt and Pd) were fabricated through a facile strategy for the first time. The PtPd@NCS nanocomposites were obtained through reduction of K 2 PtCl 4 , H 2 PtCl 6 and Na 2 PdCl 4 species, self-polymerization of dopamine (DA) and co-assembly of Pluronic F127 using a one-pot approach. DA serves as a reductant , as well as a carbon and nitrogen source. The core-shell structure of the PtPd@NCS nanocomposites was characterized and the result indicated that Pt-Pd nanoparticle core with a diameter of approximately 15 nm was encased in the N-doped carbon shells with a thickness of approximately 35 nm. The PtPd@NCS nanocomposites were used as an electrode material to prepare acetylcholinesterase (AChE) biosensors for detecting organophosphate pesticides . The obtained AChE biosensor exhibited a linear range of 1 × 10 –14 to 1 × 10 −10 M and 1 × 10 −9 to 1 × 10 −5 M within the detection limit of 7.9 × 10 –15 M for malathion , 1 × 10 –13 to 1 × 10 −6 within the detection limit of 7.1 × 10 –14 M for chlopyrifos, and 1 × 10 –14 to 1 × 10 –11 M and 1 × 10 −10 to 1 × 10 −5 M within the detection limit of 8.6 × 10 –15 M for parathion methyl . The proposed biosensor also exhibited high selectivity, reproducibility and stability. The AChE biosensor was also applied in real samples for detecting organophosphate pesticides and exhibited acceptable recovery. This work demonstrated that the PtPd@NCS had great potential in constructing biosensors to detect organophosphate pesticides and other analytes.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2018
·Vol. 165
·期 11
·A2502
·
IF 3.662
Liang Yu,Qingfeng Yi,Guang Li,Yao Chen,Xiaokun Yang
Precious metal-free C-N composites possess great significance as replacements for Pt-based catalysts used as cathodes in fuel cells. Herein, we have fabricated the Fe/Co-doped C-N composite catalysts, marked as C-N, Co/C-N and Fe-Co/C-N, by direct pyrolysis of the dried suspensions consisting of cobalt/iron salt, dicyandiamide and glucose. For the Fe-Co/C-N catalyst, its morphological texture is characterized by Fe-Co nanoparticles and hollow bamboo-like nitrogen-doped carbon nanotubes (C-N nanotubes). The electroactivity of the prepared samples for oxygen reduction reaction (ORR) in a neutral medium has been investigated. The catalyst Fe-Co/C-N presents the highest ORR current density of 5.1 mA·cm−2 @0.8V (vs Ag/AgCl) in a neutral medium. A zinc-air battery in neutral KNO3 solution, assembled with zinc as the anode and carbon paper loaded by the prepared catalysts as the air electrode (cathode), displays excellent and stable discharge performance. The maximum power density of the Fe-Co/C-N catalyst is 32 mW·cm−2, and the continuous discharge time reaches 209, 155, 17 h at constant discharging current density of 25, 50 and 100 mA·cm−2 respectively. Simultaneously, the air electrode using the Fe-Co/C-N as the catalyst shows good cycle stability and repeatability. Results reveal that the Fe-Co/C-N is a very promising cathodic catalyst applied in neutral zinc-air battery.
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2018
·
IF 4.229
Ruijing Wang,Peng Sun,Huanwen Wang,Xuefeng Wang
Development of highly-active and noble-metal-free electrocatalysts for hydrogen evolution reaction (HER) is of critical challenge for water splitting, and optimizing the structure and the composition of the relative materials is very necessary to obtain the high-quality catalysts. Herein, a novel molybdenum carbide/N-doped carbon (Mo 2 C/NC) hybrid is fabricated by using the hierarchical polyaniline tube network as a carbon source and a reactive template, and the as-fabricated Mo 2 C/NC hybrid possesses a uniform hierarchical tube structure. The coupling of the ultrafine Mo 2 C nanoparticles and the N-doped carbon substrate provides the abundant active sites and accelerates the charge transfer process. The final Mo 2 C/NC catalyst gives the excellent catalytic activity for HER in alkaline condition, which shows a lower overpotential of 142 mV at 10 mA cm −2 and a small Tafel slope of 61 mV decade −1 in 1 M KOH.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Minhan Zou,Jie Wang,Yunru Yu,Lingyu Sun,Huan Wang,Hua Xu,Yuanjin Zhao
Inspired by natural biological machines, lots of effort has been invested in developing artificially functional micromotors which can convert energy into movement for carrying out tasks in diverse areas. Here, we present a capillary microfluidic system with dual inner injections for one-step generation of composite structured polymer micromotors with two distinct cores of platinum (Pt) nanoparticle-integrated and iron oxide (Fe3O4) nanoparticle-dispersed hydrogels. Because the flow rates of the prepolymerized fluids can be precisely tuned in the microfluidics, the diameters of the micromotors as well as the sizes and numbers of the inner cores can be well tailored to optimize the parameters of the resultant micromotors. When exposed to a hydrogen peroxide (H2O2) medium, the Pt-integrated cores of the micromotors could provide propulsion by expelling bubbles produced from the catalytic decomposition of H2O2, while the Fe3O4-dispersed cores could impart magnetic guidance for the micromotors. Benefiting from the close cooperation of these two types of cores, the micromotors were imparted with a strong propulsion and prominent recyclability for the delivery of both microscale and macroscale objects. These results manifest that this kind of composite micromotor has great diversity in various applications.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2018
·
IF 4.229
Mengchen Wu,Xianxiang Hu,Congling Li,Jian Li,Haijun Zhou,Xia Zhang,Rui Liu
High-performance non-precious metal-doped carbon catalysts for oxygen reduction reactions (ORR) are viable candidates in lieu of platinum-based catalysts. It has been universally reported that active Co–N sites combined with Fe–N sites embedded in carbon matrix represent the most promising active sites for ORR process. Benefiting from the cage-encapsulated-precursor pyrolysis strategy, herein, we fabricated a Fe–N and Co–N homogeneously doped carbon framework by one step. TEM demonstrated the ultimate product had well-defined morphology with Fe (0.54 at%), Co (0.31 at%) and N (2.94 at%) uniformly distributed into the carbon skeleton. The N 2 absorption-desorption isotherms indicated the MOF-derived catalyst had a high specific surface area of 647.6 m 2 g −1 and inherit hierarchical porosity . Significantly, such FeCo–NC catalyst outperformed a current density (5.6 mA cm −2 ) at 0.70 V (vs reversible hydrogen electrode) 1.18 times higher than that of a commercial 20 wt% Pt/C (5 mA cm −2 ) catalyst in alkaline medium , and more positive peak potential of 0.63 V than its counterparts. Its high cycling stability and immunity towards methanol crossover in a wide range pH value showed good potential to be used as cathodes in proton exchange membrane fuel cells (PEMFCs) for long term operation. This simple synthesis strategy would to some degree leverage a cage-encapsulated-precursor for tailored utility of active sites for ORR in a porous carbon framework.
✓ 已验证
产品关联
DOI
高影响因子
ChemElectroChem
·
2018
·Vol. 5
·期 24
·3901-3905
·
IF 4.446
Wen-Tao Kuang,Ze-Li Jiang,Hui Li,Jing-Xuan Zhang,Lin-Nan Zhou,Yong-Jun Li
Graphical Bond breaking and bond making : Au/Pd 63 Pt 37 nanowires are prepared in a one-pot, two-step synthesis. The tri-metallic nanowires are an excellent bi-functional catalyst, capable of electrochemically catalyzing ethanol oxidation (C−C bond breaking) to output electric energy and chemically catalyzing Suzuki coupling (C−C bond formation) to produce new materials. Tri-metallic nanowire catalysts combine the synergistic effect of multiple metals with the geometrical effect of nanowires, exhibiting better catalytic performance than composition-equivalent nanospherical catalysts. However, tri-metallic nanowires are not easily produced directly because of the participation of multiple precursors and the difficulty of selecting capping agents. Herein, we develop a one-pot, two-step synthetic strategy, producing tri-metallic Au/PdPt core/shell nanowires. Moreover, the PdPt shell is an alloy composed of nanoparticles, and its Pd : Pt atomic ratio is easily adjusted by controlling reaction time. The formation of Au/PdPt nanowires is attributed to the initial formation of Au/Pd core/shell nanowire and subsequent galvanic replacement between Pd shell and PtCl 6 2− . As-prepared Au/PdPt nanowires show composition- and structure-dependent catalytic activity and durability for the electrooxidation of methanol and ethanol, and the Suzuki coupling reaction. Optimized Au/Pd 63 Pt 37 nanowire, due to its proper Pd : Pt atomic ratio and porosity of the PdPt shell, exhibits excellent catalytic activity and durability towards methanol and ethanol electrooxidation, ∼18 and 11 times in the specific activity better than that of commercial state-of-the-art Pt/C catalyst, respectively. Moreover, Au/Pd 63 Pt 37 nanowire shows the superior catalytic performance in Suzuki coupling reaction, ∼96 % at yield, far better than commercial state-of-the-art Pd/C catalyst.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Xueying Cao,Dedong Jia,Da Li,Liang Cui,Jingquan Liu
Considering the synergistic effect of transition metal phosphides and 3D structure substrates, herein, we directly deposited well-defined hierarchical radial Ni x P nanospheres on Ni foam via a facile, one-step co-electrochemical method to function as highly active flexible electrodes for both hydrogen evolution reaction and supercapacitor. Impressively, the bifunctional Ni x P/NF electrode requires an overpotential of only 63 mV to achieve a current density of 10 mA cm −2 and demonstrates a low Tafel slop of 55 mV dec −1 in 1 M KOH. Moreover, the electrochemical supercapacitor based on this hierarchical Ni x P/NF electrode also shows a superior specific capacitance of 1684 mF cm −2 (382.7 F/g) at a current density of 2 mA cm −2 and an outstanding retention ratio of 110.9% of its original capacitance value after 4000 cycles in 6 M KOH. Hopefully, excellent electrochemical performances demonstrate that this Ni x P/NF material could be a promising candidate for future applications in both hydrogen evolution reactions and supercapacitors.
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2018
·Vol. 5
·期 9
·2211-2217
·
IF 5.106
Xianghong Li,Xu Sun,Xiang Ren,Dan Wu,Xuan Kuang,Hongmin Ma,Tao Yan,Qin Wei
Electrochemical oxygen reduction is a key process for many energy storage and conversion devices, and finding highly efficient, economical, and durable electrocatalysts to replace the Pt-based catalyst for the oxygen reduction reaction (ORR) is a critical obstacle. In this article, porous Fe–N-codoped materials are obtained by pyrolysis of a defined precursor of polydopamine-coated Fe3O4 as not only template but also nitrogen and iron source. In 0.1 M KOH, the as-prepared catalyst exhibited high ORR activity (onset potential of 0.949 V and half-wave potential of 0.836 V vs. RHE), with excellent electrochemical stability, durability and remarkable tolerance toward methanol. The successful synthesis of porous nanospheres provides a novel way to explore a series of mesoporous metal electrocatalysts for energy conversion.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）