Chemical modification of MWCNTs via oxidation followed by side wall functionalization using polyethylene glycol （PEG） and octadecylamine （ODA）, separately, was studied. Different characterization techniques such a...Chemical modification of MWCNTs via oxidation followed by side wall functionalization using polyethylene glycol （PEG） and octadecylamine （ODA）, separately, was studied. Different characterization techniques such as FTIR spectrometery, thermogravimetric analysis （TGA）, scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and solubility in different solvents were performed for the oxidized MWCNTs, MWCNTs-PEG and MWCNTs-ODA. The characterization techniques proved the presence of the functional groups on the MWCNTs surface. Thermal gravimetric analysis revealed that nearly 16% （by weight） of the MWCNTs were functionalized with PEG and 39% （by weight） was functionalized with ODA.展开更多
Wide transmittance range is an essential factor for the design of infrared optical materials.Traditionally,the designs of mid-far infrared crystals have focused on oxygenfree systems of chalcogenides and pnictides.Nev...Wide transmittance range is an essential factor for the design of infrared optical materials.Traditionally,the designs of mid-far infrared crystals have focused on oxygenfree systems of chalcogenides and pnictides.Nevertheless,the introduction of elements with large atomic numbers,such as the lone-pair cation Pb^(2+) and halogen anion I^(-),based on the oxyhalides,can broaden the infrared transmittance range.Thus,two new polymorphs of Pb(Ⅱ)-containing oxyhalides,Pb_(14)O_(8)I_(12)(α-POI)and Pb_(7)O_(4)I_(6)(β-POI),are successfully synthesized via the high-temperature solution method.Interestingly,they crystallize in the same space group,P1,and present unprecedented[O_(8)Pb_(14)]clusters from the perspective of oxocentered[OPb_(4)]basic units.Remarkably,POI exhibits a quite wide transparent range(0.47-16.0μm),which enlightens the oxyhalides with prominent infrared optical properties.Additionally,the first principles calculations show that they have large birefringence(0.139 and 0.108 for α-and β-POI at 1064 nm,respectively),which makes POI promising infrared optical materials.展开更多
文摘Chemical modification of MWCNTs via oxidation followed by side wall functionalization using polyethylene glycol （PEG） and octadecylamine （ODA）, separately, was studied. Different characterization techniques such as FTIR spectrometery, thermogravimetric analysis （TGA）, scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and solubility in different solvents were performed for the oxidized MWCNTs, MWCNTs-PEG and MWCNTs-ODA. The characterization techniques proved the presence of the functional groups on the MWCNTs surface. Thermal gravimetric analysis revealed that nearly 16% （by weight） of the MWCNTs were functionalized with PEG and 39% （by weight） was functionalized with ODA.
基金supported by the Youth Innovation Promotion Association of Chinese Academy of Sciences(CAS)(2020429)the National Natural Science Foundation of China(22122509,52002398 and 11774414)+3 种基金the West Light Foundation of the CAS(2019-YDYLTD-002)the International Partnership Program of CAS(1A1365KYSB20200008)the Instrument Developing Project of CAS(GJJSTD20200007)the Science and Technology Service Network Initiative of CAS(KFJ-STS-QYZD-130)。
文摘Wide transmittance range is an essential factor for the design of infrared optical materials.Traditionally,the designs of mid-far infrared crystals have focused on oxygenfree systems of chalcogenides and pnictides.Nevertheless,the introduction of elements with large atomic numbers,such as the lone-pair cation Pb^(2+) and halogen anion I^(-),based on the oxyhalides,can broaden the infrared transmittance range.Thus,two new polymorphs of Pb(Ⅱ)-containing oxyhalides,Pb_(14)O_(8)I_(12)(α-POI)and Pb_(7)O_(4)I_(6)(β-POI),are successfully synthesized via the high-temperature solution method.Interestingly,they crystallize in the same space group,P1,and present unprecedented[O_(8)Pb_(14)]clusters from the perspective of oxocentered[OPb_(4)]basic units.Remarkably,POI exhibits a quite wide transparent range(0.47-16.0μm),which enlightens the oxyhalides with prominent infrared optical properties.Additionally,the first principles calculations show that they have large birefringence(0.139 and 0.108 for α-and β-POI at 1064 nm,respectively),which makes POI promising infrared optical materials.
