乙二胺杂化锗酸锌纳米带的绿色合成及其对铀酰离子的吸附与检测

Green Synthesis of an Ethylenediamine Hybrid Zinc Germanate Nanoribbon and Its Application in Adsorption and Detection of Uranyl Ions

该文采用水热法合成了一种新型乙二胺杂化的锗酸锌纳米带(NH2-Zn_(2)GeO_(4)NRs),并用于铀酰离子(UO_(2)^(2+))的检测和吸附。利用透射电子显微镜(TEM)、傅里叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)、X射线衍射(XRD)、紫外-可见吸收光谱(UV-Vis)以及荧光光谱等对纳米带的结构及其光学特性进行了表征。结果表明NH_(2)-Zn_(2)GeO_(4)NRs表面含有大量的-Ge-O-H和-NH_(2)基团,为UO22+的检测和吸附提供了丰富的结合位点。此外NH_(2)-Zn_(2)GeO_(4)NRs可高效、高选择性地吸附和检测UO_(2)^(2+),其对UO_(2)^(2+)的吸附符合Langmuir等温模型,最大吸附量为190 mg/g。基于天线效应,UO_(2)^(2+)与NH_(2)-Zn_(2)GeO_(4)NRs的相互作用可打开UO_(2)^(2+)的绿色荧光,据此建立了灵敏的UO_(2)^(2+)检测方法,线性范围为0~45μmol/L,检出限达0.202μmol/L。对实际样品的加标回收率为87.2%~102%,相对标准偏差低于10%。制备的NH2-Zn_(2)GeO_(4)NRs在实现UO_(2)^(2+)检测的同时可对其进行吸附,在实际水样检测中具有广泛的应用价值。

A kind of novel ethylenediamine hybrid zinc germanate nanoribbons(NH_(2)-Zn_(2)GeO_(4) NRs)for adsorption and detection of uranyl ions was synthesized by hydrothermal synthesis.The structure and optical properties of NH_(2)-Zn_(2)GeO_(4) NRs were characterized by transmission electron mi⁃croscopy(TEM),Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD),thermogravimetric analysis(TG),X-ray energy spectrometry(EDS),ultraviolet-visible absorption spectrum(UV-Vis)and fluorescence spectroscopy.The re⁃sults showed that the NH_(2)-Zn_(2)GeO_(4) NRs have a crisscross band structure with good crystallinity and good thermal stability.Meanwhile,the surface of NH_(2)-Zn_(2)GeO_(4) NRs contains rich amino groups,greatly improving the dispersion of the nanoribbons and facilitating the coordination of UO_(2)^(2+)with the surface amino groups,and then adsorbing UO_(2)^(2+).Furthermore,the interaction between the-Ge-O-H group on the surface of zinc germanate nanoribbons and UO_(2)^(2+),based on the antenna effect,turns on green fluorescence to realize the fluorescence detection of UO_(2)^(2+).Therefore,the NH_(2)-Zn_(2)GeO_(4) NRs could selectively and efficiently adsorb UO_(2)^(2+),and their adsorption of uranyl ions con⁃forms to Langmuir isotherm model,with a maximum adsorption capacity of 190 mg/g.On the other hand,a sensitive detection method for UO_(2)^(2+)was established based on the interaction between UO_(2)^(2+)and NH_(2)-Zn_(2)GeO_(4) NRs,which could turn on green fluorescence,with a linear range of 0-45μmol/L and a detection limit as low as 0.202μmol/L.Results showed that only UO_(2)^(2+)can make NH_(2)-Zn_(2)GeO_(4) NRs solution produce green fluorescence,while other ions have no fluorescence en⁃hancement effect,indicating that the nano material has high selectivity and strong anti-interference ability.The method was successfully applied to the concentration analysis of UO_(2)^(2+)in tap water,lake water,river water and sea water.The recoveries for the actual samples ranged from 87.2%to 102%,with the relative standard deviations less than 10%.Therefore,the prepared NH_(2)-Zn_(2)GeO_(4) NRs could be used for the simultaneous adsorption and detection of UO_(2)^(2+),which has a wide application value in detection of actual water samples.