Herein,we report on magnetic microspheres with numerous imine groups on the surface,which have great potential for U(VI)recovery in seawater.Hyperbranched polyethylenimine(HPEI)was covalently grafted onto the surface ...Herein,we report on magnetic microspheres with numerous imine groups on the surface,which have great potential for U(VI)recovery in seawater.Hyperbranched polyethylenimine(HPEI)was covalently grafted onto the surface of the core–shell structured microspheres Fe_(3)O_(4)@SiO_(2).The microstructure and chemical composition of Fe_(3)O_(4)@SiO_(2)-HPEI were comprehensively characterized.Consequently,the adsorption performance at low concentrations(3–30μg L^(−1))under simulated seawater was investigated and the removal rate reached more than 90%.The superior performance of the Fe_(3)O_(4)@SiO_(2)-HPEI is attributed to electrostatic force and chemical bonding(between amine/imine groups and U(VI)).We recommend,therefore,Fe_(3)O_(4)@SiO_(2)-HPEI as a prospective alternative adsorbent in U(VI)recovery from seawater.展开更多
Semiconductor materials based on composite metal oxide nanomaterials have attracted enormous attention recently due to their unique chemical and electrical properties.P-p heterojunction CuO/CuCo_(2)O_(4)nanotubes were...Semiconductor materials based on composite metal oxide nanomaterials have attracted enormous attention recently due to their unique chemical and electrical properties.P-p heterojunction CuO/CuCo_(2)O_(4)nanotubes were synthesized by simple single-capillary electrospinning technology followed by a heat treatment process to achieve the tubular structure.Nanotubes with diameters in the range of 60-70 nm with a large specific surface area of as-prepared materials have been demonstrated by scanning electron microscopy(SEM),transmission electron microscopy(TEM),and N_(2)absorption-desorption isothermal analysis(Brunauer-Emmett-Teller,BET)of composite CuO/CuCo_(2)O_(4)nanotubes.The composition and crystal structure of CuO/CuCo_(2)O_(4)nanotubes were confirmed by X-ray diffraction,energy-dispersive X-ray spectrometry(EDX)analyses,and X-ray photoelectron spectroscopy(XPS).Room temperature gas sensing performance of CuO/CuCo_(2)O_(4)nanotubes toward n-propanol gas was investigated,where a response of 14 with rapid response(6.3 s)-recovery(4.1 s)times have been measured for 10 ppm n-propanol at room temperature.The stability,selectivity and sensing mechanism of p-p heterostructure CuO/CuCo_(2)O_(4)nanotubes were investigated and discussed as well.展开更多
基金supported by the National Natural Science Foundation of China(NSFC51603053)the Major Project of Science and Technology of Heilongjiang Province(GA14A101)+4 种基金the Fundamental Research Funds of the Central University(HEUCFM171010)the Natural Science Foundation of Heilongjiang Province(B2015021)the International Science&Technology Cooperation Program of China(2015DFA50050)the Application Technology Research and Development Projects of Harbin(2015RAQXJ038)the Application Technology Research and Development Plan of Heilongjiang Province(GX16A009).
文摘Herein,we report on magnetic microspheres with numerous imine groups on the surface,which have great potential for U(VI)recovery in seawater.Hyperbranched polyethylenimine(HPEI)was covalently grafted onto the surface of the core–shell structured microspheres Fe_(3)O_(4)@SiO_(2).The microstructure and chemical composition of Fe_(3)O_(4)@SiO_(2)-HPEI were comprehensively characterized.Consequently,the adsorption performance at low concentrations(3–30μg L^(−1))under simulated seawater was investigated and the removal rate reached more than 90%.The superior performance of the Fe_(3)O_(4)@SiO_(2)-HPEI is attributed to electrostatic force and chemical bonding(between amine/imine groups and U(VI)).We recommend,therefore,Fe_(3)O_(4)@SiO_(2)-HPEI as a prospective alternative adsorbent in U(VI)recovery from seawater.
基金supported by the National Natural Science Foundation of China(NSFC51402065)International Science&Technology Cooperation Program of China(2015DFR50050)+2 种基金Natural Science Foundation of Heilongjiang Province(B201404)the Major Project of Science and Technology of Heilongjiang Province(GA14A101)Fundamental Research Funds of the Central University(HEUCFM).
文摘Semiconductor materials based on composite metal oxide nanomaterials have attracted enormous attention recently due to their unique chemical and electrical properties.P-p heterojunction CuO/CuCo_(2)O_(4)nanotubes were synthesized by simple single-capillary electrospinning technology followed by a heat treatment process to achieve the tubular structure.Nanotubes with diameters in the range of 60-70 nm with a large specific surface area of as-prepared materials have been demonstrated by scanning electron microscopy(SEM),transmission electron microscopy(TEM),and N_(2)absorption-desorption isothermal analysis(Brunauer-Emmett-Teller,BET)of composite CuO/CuCo_(2)O_(4)nanotubes.The composition and crystal structure of CuO/CuCo_(2)O_(4)nanotubes were confirmed by X-ray diffraction,energy-dispersive X-ray spectrometry(EDX)analyses,and X-ray photoelectron spectroscopy(XPS).Room temperature gas sensing performance of CuO/CuCo_(2)O_(4)nanotubes toward n-propanol gas was investigated,where a response of 14 with rapid response(6.3 s)-recovery(4.1 s)times have been measured for 10 ppm n-propanol at room temperature.The stability,selectivity and sensing mechanism of p-p heterostructure CuO/CuCo_(2)O_(4)nanotubes were investigated and discussed as well.
