Iron oxide nanoparticles（FeOx NPs, 5–30 nm size） prepared via laser ablation in liquid were supported onto Indium Tin Oxide conductive glass slides by magnetophoretic deposition（MD） technique. The resulting Fe O ...Iron oxide nanoparticles（FeOx NPs, 5–30 nm size） prepared via laser ablation in liquid were supported onto Indium Tin Oxide conductive glass slides by magnetophoretic deposition（MD） technique. The resulting Fe O x@ITO electrodes are characterized by a low amount of iron coverage of 16–50 nmol/cm^2,and show electrocatalytic activity towards water oxidation in neutral phosphate buffer pH 7 with 0.58 V overpotential and quantitative Faradaic efficiency towards oxygen production. XPS analysis on the oxygen region of the FeOx films reveals a substantial hydration of the surface after catalysis, recognized as a crucial step to access reactivity.展开更多
Black phosphorus(BP)exhibits a significant chemical reactivity toward transition metals,which is strongly dependent on its electronic and morphological features.Using as a case study metal Co atoms deposited by physic...Black phosphorus(BP)exhibits a significant chemical reactivity toward transition metals,which is strongly dependent on its electronic and morphological features.Using as a case study metal Co atoms deposited by physical vapor deposition on chemically exfoliated BP thinfilms,we document that environmentally oxidized BP edges react immediately with the formation of Co(Ⅱ)-POx species,but later also the basal plane strongly reacts,already at room temperature,to form an interfacial phosphide.Atomically resolved scanning tunneling microscopy data reveal the formation of a Co_(2)P(112)layer,upon which the further growth of metal Co nanoparticles takes place.X-ray photoemission spectroscopy data show similar inter facial reactions also for atomic W,suggesting a quite general behavior.The electrochemical and photo electrocatalytic properties of the resulting metal-BP nanohybrids are investigated by linear sweep voltam metry and electrochemical impedance spectroscopy.The Co-BP nanohybrid shows a marked stability in acid media and a significant increase of the electrocatalytic activity for the hydrogen evolution reaction with respect to bare BP,due to the formation of a very stable phosphide phase,and even an interesting photoactivity connected to the formation of p-n junction between BP and Co_(2)P.On the other hand,the W-BP nanohybrid exhibits a modest performance in the electrocatalytic production of hydrogen because of the formation of less active oxide phases as a consequence of environmental oxidation.展开更多
Graphene-h-BN hybrid nanostructures are grown in one step on the Pt(111) surface by ultra-high vacuum chemical vapor deposition using a single precursor,the dimethylamino borane complex.By varying the deposition condi...Graphene-h-BN hybrid nanostructures are grown in one step on the Pt(111) surface by ultra-high vacuum chemical vapor deposition using a single precursor,the dimethylamino borane complex.By varying the deposition conditions,different nanostructures ranging from a fully continuous hybrid monolayer to well-separated Janus nanodots can be obtained.The growth starts with heterogeneous nucleation on morphological defects such as Pt step edges and proceeds by the addition of small clusters formed by the decomposition of the dimethylamino borane complex.Scanning tunneling microscopy measurements indicate that a sharp zigzag in-plane boundary is formed when graphene grows aligned with the Pt substrate and consequently with the h-BN layer as well.When graphene is rotated by 30°,the graphene armchair edges are seamlessly connected to h-BN zigzag edges.This is confirmed by a thorough density functional theory (DFT) study.Angle resolved photoemission spectroscopy (ARPES) data suggests that both h-BN and graphene present the typical electronic structure of self-standing non-interacting materials.展开更多
Single-atom metal-incorporated carbon nanomaterials(CMs)have shown great potential towards broad catalytic applications.In this work,we show that N-doped porous CMs embedded with redox-able Zn atoms exhibit superior c...Single-atom metal-incorporated carbon nanomaterials(CMs)have shown great potential towards broad catalytic applications.In this work,we show that N-doped porous CMs embedded with redox-able Zn atoms exhibit superior capacitive performance.High Zn(~2.72 at.%)/N(~12.51 at.%)doping were realized by incorporating Zn2+and benzamide into the condensation and carbonization of formamide and subsequent annealing at 900℃.The Zn and N species are mutually benefited during the formation of ZnN4 motif.The as-obtained Zn1NC material affords a very large capacitance of 621 F·g^(−1)(at 0.1 A·g^(−1)),superior rate capability(~65%retention at 100 A·g^(−1)),and excellent cycling stability(0.00044%per cycle at 10 A·g^(−1)).These merits are attributed to the high Zn/N loading,atomic Zn-boosted pseudocapacitive behavior,large specific surface area(~1,085 m^(2)·g^(−1)),and rich pore hierarchy,thus ensuring both large pseudo-capacitance(e.g.,~37.9%at 10 mV·s^(−1))and double-layer capacitance.Besides of establishing a new type of high Zn/N-loading carbon materials,our work uncovers the capacitive roles of atomically dispersed metals in CMs.展开更多
A frontier topic in nanotechnology is the realization of multifunctional nanoparticles （NPs） via the appropriate combination of different elements of the periodic table. The coexistence of Fe and Ag in the same nano...A frontier topic in nanotechnology is the realization of multifunctional nanoparticles （NPs） via the appropriate combination of different elements of the periodic table. The coexistence of Fe and Ag in the same nanostructure, for instance, is interesting for nanophotonics, nanomedicine, and catalysis. However, alloying of Fe and Ag is inhibited for thermodynamic reasons. Here, we describe the synthesis of Fe-doped Ag NPs via laser ablation in liquid solution, bypassing thermodynamics constraints. These NPs have an innovative structure consisting of a scaffold of face-centered cubic metal Ag alternating with disordered Ag-Fe alloy domains, all arranged in a truffle-like morphology. The Fe-Ag NPs exhibit the plasmonic properties of Ag and the magnetic response of Fe-containing phases, and the surface of the Fe-Ag NPs can be functionalized in one step with thiolated molecules. Taking advantage of the multiple properties of Fe-Ag NPs, the magnetophoretic amplification of plasmonic properties is demonstrated with proof-of-concept surface-enhanced Raman scattering and photothermal heating experiments. The synthetic approach is of general applicability and virtually permits the preparation of a large variety of multi-element NPs in one step.展开更多
基金supported by the Italian Ministero dell’Università e della Ricerca (MIUR), (FIRB RBAP11C58Y, "Nano Solar" and PRIN 2010 "Hi-Phuture")COST action CM1205 "CARISMA: CAtalytic Rout Ines for Small Molecule Activation"
文摘Iron oxide nanoparticles（FeOx NPs, 5–30 nm size） prepared via laser ablation in liquid were supported onto Indium Tin Oxide conductive glass slides by magnetophoretic deposition（MD） technique. The resulting Fe O x@ITO electrodes are characterized by a low amount of iron coverage of 16–50 nmol/cm^2,and show electrocatalytic activity towards water oxidation in neutral phosphate buffer pH 7 with 0.58 V overpotential and quantitative Faradaic efficiency towards oxygen production. XPS analysis on the oxygen region of the FeOx films reveals a substantial hydration of the surface after catalysis, recognized as a crucial step to access reactivity.
基金supported by the following projects:financial support from the Italian MIUR(PRIN 2015:SMARTNESS,2015K7FZLH,PRIN2017:Multi-e,20179337R7)MAECI Italy-China bilateral project(GINSENG,PGR00953)+1 种基金The Cariparo foundation is acknowledged for funding(project Synergy,Progetti di Eccellenza 2018)Thanks are also expressed to the European Research Council(ERC)under the European Union’s Horizon 2020 research and inno vation program(Grant Agreement No.670173)for funding the project PHOSFUN“Phosphorene functionalization:a new plat form for advanced multifunctional materials”through an ERC Advanced Grant to MP.
文摘Black phosphorus(BP)exhibits a significant chemical reactivity toward transition metals,which is strongly dependent on its electronic and morphological features.Using as a case study metal Co atoms deposited by physical vapor deposition on chemically exfoliated BP thinfilms,we document that environmentally oxidized BP edges react immediately with the formation of Co(Ⅱ)-POx species,but later also the basal plane strongly reacts,already at room temperature,to form an interfacial phosphide.Atomically resolved scanning tunneling microscopy data reveal the formation of a Co_(2)P(112)layer,upon which the further growth of metal Co nanoparticles takes place.X-ray photoemission spectroscopy data show similar inter facial reactions also for atomic W,suggesting a quite general behavior.The electrochemical and photo electrocatalytic properties of the resulting metal-BP nanohybrids are investigated by linear sweep voltam metry and electrochemical impedance spectroscopy.The Co-BP nanohybrid shows a marked stability in acid media and a significant increase of the electrocatalytic activity for the hydrogen evolution reaction with respect to bare BP,due to the formation of a very stable phosphide phase,and even an interesting photoactivity connected to the formation of p-n junction between BP and Co_(2)P.On the other hand,the W-BP nanohybrid exhibits a modest performance in the electrocatalytic production of hydrogen because of the formation of less active oxide phases as a consequence of environmental oxidation.
文摘Graphene-h-BN hybrid nanostructures are grown in one step on the Pt(111) surface by ultra-high vacuum chemical vapor deposition using a single precursor,the dimethylamino borane complex.By varying the deposition conditions,different nanostructures ranging from a fully continuous hybrid monolayer to well-separated Janus nanodots can be obtained.The growth starts with heterogeneous nucleation on morphological defects such as Pt step edges and proceeds by the addition of small clusters formed by the decomposition of the dimethylamino borane complex.Scanning tunneling microscopy measurements indicate that a sharp zigzag in-plane boundary is formed when graphene grows aligned with the Pt substrate and consequently with the h-BN layer as well.When graphene is rotated by 30°,the graphene armchair edges are seamlessly connected to h-BN zigzag edges.This is confirmed by a thorough density functional theory (DFT) study.Angle resolved photoemission spectroscopy (ARPES) data suggests that both h-BN and graphene present the typical electronic structure of self-standing non-interacting materials.
基金the National Natural Science Foundation of China(Nos.22071137 and 21701101)the Shandong Scientific Research Awards Foundation for Outstanding Young Scientists(No.ZR2018JL010)+1 种基金the Natural Science Foundation of Shandong Province(No.ZR2020MB045)the Program for Tsingtao Al-ion Power and Energy-storage Battery Research Team in the University(No.17-2-1-1-zhc).
文摘Single-atom metal-incorporated carbon nanomaterials(CMs)have shown great potential towards broad catalytic applications.In this work,we show that N-doped porous CMs embedded with redox-able Zn atoms exhibit superior capacitive performance.High Zn(~2.72 at.%)/N(~12.51 at.%)doping were realized by incorporating Zn2+and benzamide into the condensation and carbonization of formamide and subsequent annealing at 900℃.The Zn and N species are mutually benefited during the formation of ZnN4 motif.The as-obtained Zn1NC material affords a very large capacitance of 621 F·g^(−1)(at 0.1 A·g^(−1)),superior rate capability(~65%retention at 100 A·g^(−1)),and excellent cycling stability(0.00044%per cycle at 10 A·g^(−1)).These merits are attributed to the high Zn/N loading,atomic Zn-boosted pseudocapacitive behavior,large specific surface area(~1,085 m^(2)·g^(−1)),and rich pore hierarchy,thus ensuring both large pseudo-capacitance(e.g.,~37.9%at 10 mV·s^(−1))and double-layer capacitance.Besides of establishing a new type of high Zn/N-loading carbon materials,our work uncovers the capacitive roles of atomically dispersed metals in CMs.
文摘A frontier topic in nanotechnology is the realization of multifunctional nanoparticles （NPs） via the appropriate combination of different elements of the periodic table. The coexistence of Fe and Ag in the same nanostructure, for instance, is interesting for nanophotonics, nanomedicine, and catalysis. However, alloying of Fe and Ag is inhibited for thermodynamic reasons. Here, we describe the synthesis of Fe-doped Ag NPs via laser ablation in liquid solution, bypassing thermodynamics constraints. These NPs have an innovative structure consisting of a scaffold of face-centered cubic metal Ag alternating with disordered Ag-Fe alloy domains, all arranged in a truffle-like morphology. The Fe-Ag NPs exhibit the plasmonic properties of Ag and the magnetic response of Fe-containing phases, and the surface of the Fe-Ag NPs can be functionalized in one step with thiolated molecules. Taking advantage of the multiple properties of Fe-Ag NPs, the magnetophoretic amplification of plasmonic properties is demonstrated with proof-of-concept surface-enhanced Raman scattering and photothermal heating experiments. The synthetic approach is of general applicability and virtually permits the preparation of a large variety of multi-element NPs in one step.
