Graphene oxide and Ni-Al layered double hydroxides(GO@LDH) nanocomposites were synthesized via a one-pot hydrothermal process,and characterized by X-ray diffraction(XRD),Fourier transformed infrared spectroscopy(FTIR)...Graphene oxide and Ni-Al layered double hydroxides(GO@LDH) nanocomposites were synthesized via a one-pot hydrothermal process,and characterized by X-ray diffraction(XRD),Fourier transformed infrared spectroscopy(FTIR),scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS) and Raman spectroscopy in detail.The exploration of U(VI) sorption on GO@LDH surface was performed as a function of ionic strength,solution pH,contact time,U(VI) initial concentrations and temperature.Results of Langmuir isotherms showed that the sorption capacity of GO@LDH(160 mg/g) was much higher than those of LDH(69 mg/g) and GO(92 mg/g).The formed surface complexes between surface oxygen-containing functional groups of GO@LDH and U(VI) turned out to be the interaction mechanism of U(VI) with GO@LDH.According to the thermodynamic studies results,the sorption interaction was actually a spontaneous and endothermic chemical process.The sorption isotherms were better fitted with the Langmuir model compared with other models,which suggested the interaction was mainly dominated by mono layer coverage.The GO@LDH nanocomposites provide potential applications as adsorbents in the enrichment of radionuclides from wastewater in nuclear waste management and environmental remediation.展开更多
以TiCl_4为钛源,采用简单易行的溶胶凝胶法低温制备锐钛矿型TiO_2光催化剂。采用XRD、SEM、DRS和LRS等手段对所制备的锐钛矿型TiO2催化剂的结构进行了表征。通过光催化还原U(Ⅵ)效果研究了锐钛矿型TiO_2光催化剂的光催化还原活性。结果...以TiCl_4为钛源,采用简单易行的溶胶凝胶法低温制备锐钛矿型TiO_2光催化剂。采用XRD、SEM、DRS和LRS等手段对所制备的锐钛矿型TiO2催化剂的结构进行了表征。通过光催化还原U(Ⅵ)效果研究了锐钛矿型TiO_2光催化剂的光催化还原活性。结果表明,催化剂在紫外光区有较强的吸收,纳米锐钛矿型TiO_2的吸收带边分别为398 nm,纳米TiO_2样品的禁带宽度为3.14 e V。锐钛矿型TiO_2对U(Ⅵ)的光催化还原活性可达到99%。为高效光催化还原技术处理低浓度含铀废水提供实验依据。展开更多
基金supported by the National Natural Science Foundation of China(91326202,21225730,21577032)the Fundamental ResearchFunds forthe Central Universities(JB2015001)
文摘Graphene oxide and Ni-Al layered double hydroxides(GO@LDH) nanocomposites were synthesized via a one-pot hydrothermal process,and characterized by X-ray diffraction(XRD),Fourier transformed infrared spectroscopy(FTIR),scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS) and Raman spectroscopy in detail.The exploration of U(VI) sorption on GO@LDH surface was performed as a function of ionic strength,solution pH,contact time,U(VI) initial concentrations and temperature.Results of Langmuir isotherms showed that the sorption capacity of GO@LDH(160 mg/g) was much higher than those of LDH(69 mg/g) and GO(92 mg/g).The formed surface complexes between surface oxygen-containing functional groups of GO@LDH and U(VI) turned out to be the interaction mechanism of U(VI) with GO@LDH.According to the thermodynamic studies results,the sorption interaction was actually a spontaneous and endothermic chemical process.The sorption isotherms were better fitted with the Langmuir model compared with other models,which suggested the interaction was mainly dominated by mono layer coverage.The GO@LDH nanocomposites provide potential applications as adsorbents in the enrichment of radionuclides from wastewater in nuclear waste management and environmental remediation.
文摘以TiCl_4为钛源,采用简单易行的溶胶凝胶法低温制备锐钛矿型TiO_2光催化剂。采用XRD、SEM、DRS和LRS等手段对所制备的锐钛矿型TiO2催化剂的结构进行了表征。通过光催化还原U(Ⅵ)效果研究了锐钛矿型TiO_2光催化剂的光催化还原活性。结果表明,催化剂在紫外光区有较强的吸收,纳米锐钛矿型TiO_2的吸收带边分别为398 nm,纳米TiO_2样品的禁带宽度为3.14 e V。锐钛矿型TiO_2对U(Ⅵ)的光催化还原活性可达到99%。为高效光催化还原技术处理低浓度含铀废水提供实验依据。
