The nucleation and growth mechanism of nanoparticles is an important theory,which can guide the preparation of nanomaterials.However,it is still lacking in direct observation on the details of the evolution of interme...The nucleation and growth mechanism of nanoparticles is an important theory,which can guide the preparation of nanomaterials.However,it is still lacking in direct observation on the details of the evolution of intermediate state structure during nucleation and growth.In this work,the evolution process of bismuth nanoparticles induced by electron beam was revealed by in-situ transmission electron microscopy(TEM)at atomic scale.The experimental results demonstrate that the size,stable surface and crystallographic defect have important influences on the growth of Bi nanoparticles.Two non-classical growth paths including single crystal growth and polycrystalline combined growth,as well as,corresponding layer-by-layer growth mechanism along{012}stable crystal plane of Bi nanoparticles with dodecahedron structure were revealed by in-situ TEM directly.These results provide important guidance and a new approach for in-depth understanding of the nucleation and growth kinetics of nanoparticles.展开更多
Electrochemical analysis is a promising technique for detecting biotoxic and non-biodegradable heavy metals.This article proposes a novel composite electrode based on a polyaniline(PANi)fra mework doped with bismuth n...Electrochemical analysis is a promising technique for detecting biotoxic and non-biodegradable heavy metals.This article proposes a novel composite electrode based on a polyaniline(PANi)fra mework doped with bismuth nanoparticle@graphene oxide multi-walled carbon nano tubes(Bi NPs@GO-MWCNTs)for the simultaneous detection of multiple heavy metal ions.Composite electrodes are prepared on screenprinted electrodes(SPCEs)using an efficient dispensing technique.We used a SM200 SX-3 A dispenser to load a laborato ry-specific ink with optimized viscosity and adhesion to draw a pattern on the work area.The SPCE was used as substrate to facilitate cost-effective and more convenient real-time detection technology.Electrochemical techniques,such as cyclic voltammetry and differential pulse voltammetry,were used to demonstrate the sensing capabilities of the proposed sensor,The sensitivity,limit of detection,and linear range of the PANi-Bi NPs@GO-MWCNT electrode are 2.57×10^(2)μA Lμmol^(-1) cm^-2,0.01 nmol/L,and 0.01 nmol/L-5 mmol/L and 0.15×10^(-1)μALμmol^(-1) cm^-2,0.5 nmol/L,and 0.5 nmol/L-5 mmol/L for mercury ion(Hg(Ⅱ))and copper ion(Cu(Ⅱ))detection,respectively.In addition,the electrode exhibits a good selectivity and repeatability for Hg(Ⅱ)and Cu(Ⅱ)sensing when tested in a complex heavy metal ion solution.The constructed electrode system exhibits a detection performance superior to similar methods and also increases the types of heavy metal ions that can be detected.Therefore,the proposed device can be used as an efficient sensor for the detection of multiple heavy metal ions in complex environments.展开更多
Plasmonic bismuth(Bi^0)nanoparticle-decorated flower-like CeO2-δ(Bi^0/CeO2-δ)photocatalysts with abundant oxygen vacancies(OVs)were synthesized via a solvothermal method.The OVs can not only improve the separation o...Plasmonic bismuth(Bi^0)nanoparticle-decorated flower-like CeO2-δ(Bi^0/CeO2-δ)photocatalysts with abundant oxygen vacancies(OVs)were synthesized via a solvothermal method.The OVs can not only improve the separation of electron-hole pairs,but also facilitate the adsorption and activation of gas molecules(NO/O2).In addition,the Bi^0 nanoparticles can enhance the visible light response and prevent the recombination of charge carriers by virtue of the surface plasmon resonance(SPR)effect,achieving an excellent ability for NO elimination and NO2 inhibition under visible light irradiation.Density functional theory(DFT)calculations confirm that the Schottky barrier between Bi^0 and CeO2-δaccompanied with the OVs are pivotal for the migration of photogenerated charge carriers to involve in the photocatalytic NO removal.Trapping experiments and in situ FTIR spectroscopy were conducted to explore the mechanism of the photocatalytic NO removal,suggesting that the photocatalytic NO removal can be significantly enhanced by introducing abundant OVs and the involvement of Bi^0 metal nanoparticles.展开更多
基金Funded by the National Natural Science Foundation of China(No.52103285)the 111 National Project(No.B20002)。
文摘The nucleation and growth mechanism of nanoparticles is an important theory,which can guide the preparation of nanomaterials.However,it is still lacking in direct observation on the details of the evolution of intermediate state structure during nucleation and growth.In this work,the evolution process of bismuth nanoparticles induced by electron beam was revealed by in-situ transmission electron microscopy(TEM)at atomic scale.The experimental results demonstrate that the size,stable surface and crystallographic defect have important influences on the growth of Bi nanoparticles.Two non-classical growth paths including single crystal growth and polycrystalline combined growth,as well as,corresponding layer-by-layer growth mechanism along{012}stable crystal plane of Bi nanoparticles with dodecahedron structure were revealed by in-situ TEM directly.These results provide important guidance and a new approach for in-depth understanding of the nucleation and growth kinetics of nanoparticles.
基金the Tianjin Natural Science Foundation(Nos.18JCZDJC998007JCQNJC00900)+4 种基金National Natural Science Foundation of China(No.51502203)Tianjin Young Overseas High-level Talent Plans(No.01001502)Tianjin Science and Technology Foundation(No.17ZXZNGX00090)Tianjin Distinguished Professor Foundation of Young ResearchersTianjin Development Program for Innovation and Entrepreneurship。
文摘Electrochemical analysis is a promising technique for detecting biotoxic and non-biodegradable heavy metals.This article proposes a novel composite electrode based on a polyaniline(PANi)fra mework doped with bismuth nanoparticle@graphene oxide multi-walled carbon nano tubes(Bi NPs@GO-MWCNTs)for the simultaneous detection of multiple heavy metal ions.Composite electrodes are prepared on screenprinted electrodes(SPCEs)using an efficient dispensing technique.We used a SM200 SX-3 A dispenser to load a laborato ry-specific ink with optimized viscosity and adhesion to draw a pattern on the work area.The SPCE was used as substrate to facilitate cost-effective and more convenient real-time detection technology.Electrochemical techniques,such as cyclic voltammetry and differential pulse voltammetry,were used to demonstrate the sensing capabilities of the proposed sensor,The sensitivity,limit of detection,and linear range of the PANi-Bi NPs@GO-MWCNT electrode are 2.57×10^(2)μA Lμmol^(-1) cm^-2,0.01 nmol/L,and 0.01 nmol/L-5 mmol/L and 0.15×10^(-1)μALμmol^(-1) cm^-2,0.5 nmol/L,and 0.5 nmol/L-5 mmol/L for mercury ion(Hg(Ⅱ))and copper ion(Cu(Ⅱ))detection,respectively.In addition,the electrode exhibits a good selectivity and repeatability for Hg(Ⅱ)and Cu(Ⅱ)sensing when tested in a complex heavy metal ion solution.The constructed electrode system exhibits a detection performance superior to similar methods and also increases the types of heavy metal ions that can be detected.Therefore,the proposed device can be used as an efficient sensor for the detection of multiple heavy metal ions in complex environments.
基金supported by the National Natural Science Foundation of China(51772183,21673118 and 21972067)the Key Research and Development Program of Shaanxi Province(2018ZDCXL-SF-02-04)+1 种基金the Natural Science Foundation of Hubei Province(2019CFB225)the Fundamental Research Funds for the Central Universities(GK201903023 and GK201801005)。
文摘Plasmonic bismuth(Bi^0)nanoparticle-decorated flower-like CeO2-δ(Bi^0/CeO2-δ)photocatalysts with abundant oxygen vacancies(OVs)were synthesized via a solvothermal method.The OVs can not only improve the separation of electron-hole pairs,but also facilitate the adsorption and activation of gas molecules(NO/O2).In addition,the Bi^0 nanoparticles can enhance the visible light response and prevent the recombination of charge carriers by virtue of the surface plasmon resonance(SPR)effect,achieving an excellent ability for NO elimination and NO2 inhibition under visible light irradiation.Density functional theory(DFT)calculations confirm that the Schottky barrier between Bi^0 and CeO2-δaccompanied with the OVs are pivotal for the migration of photogenerated charge carriers to involve in the photocatalytic NO removal.Trapping experiments and in situ FTIR spectroscopy were conducted to explore the mechanism of the photocatalytic NO removal,suggesting that the photocatalytic NO removal can be significantly enhanced by introducing abundant OVs and the involvement of Bi^0 metal nanoparticles.
