The space-confined synthesis method has been an efficient way for the preparation of linear carbon chains.However,the large-scale preparation of linear carbon chains still faces many challenges due to the lack of meth...The space-confined synthesis method has been an efficient way for the preparation of linear carbon chains.However,the large-scale preparation of linear carbon chains still faces many challenges due to the lack of methods for the large-scale synthesis of precursors,such as short carbon chains(polyynes),and regulation technology for the transport of reactants in one-dimensional space.Here,we report a facile method for the rapid preparation of polyynes in large quantities using a commercial laser marking machine.Spectroscopic characterizations show that a large number of polyynes,such as C_(8)H_(2),C_(10)H_(2),C_(12)H_(2),and C_(14)H_(2),can be produced by ablating the graphite plate immersed in the organic liquid using a laser marking machine.The results of in situ Raman spectroscopy investigation of C_(2n)H_(2)-filled single-walled carbon nanotubes further confirm that a variety of polyyne molecules are synthesized.Meanwhile,in situ Raman spectroscopy also shows that the local heating treatment can accelerate the filling process of C_(2n)H_(2)into one-dimensional channels.This work provides new insights into the study of linear carbon chains and space-confined synthesis methods.展开更多
New Aurivillius phase Bi9Fe4.7Me0.3Ti3O27(Me = Fe, Co, Ni, Mn) oxides have been prepared using a citrate combustion method. X-ray diffraction on powders and high-resolution transmission electron microscopy investigati...New Aurivillius phase Bi9Fe4.7Me0.3Ti3O27(Me = Fe, Co, Ni, Mn) oxides have been prepared using a citrate combustion method. X-ray diffraction on powders and high-resolution transmission electron microscopy investigation confirmed that the Bi9Fe4.7Me0.3Ti3O27 samples are with an eight-layer structure. Both ferromagnetic and ferroelectric investigations suggested that Co or Ni substitution could enhance their multiferroic properties,while Mn substitution depressed them. Among all the samples, Bi9Fe4.7Co0.3Ti3O27 sample exhibits the largest remnant polarization of Pr*3.8 l C/cm2, and the largest remnant magnetization of Mr*0.06 lB/f.u. with a Curie temperature about 764 K, while the Bi9Fe4.7Ni0.3Ti3O27 sample has the largest spontaneous magnetization(0.26 lB/f.u.). The improved ferromagnetic properties ofboth Bi9Fe4.7Co0.3Ti3O27 and Bi9Fe4.7Ni0.3Ti3O27 can be ascribed to the spin canting of magnetic ion-based sublattices via the Dzyaloshinskii–Moriya interaction and also the magnetic ions exchanging interactions(Fe3–O–Co3or Fe3–O–Ni3).展开更多
基金Project supported by the Nanhu Scholars Program for Young Scholars of Xinyang Normal University
文摘The space-confined synthesis method has been an efficient way for the preparation of linear carbon chains.However,the large-scale preparation of linear carbon chains still faces many challenges due to the lack of methods for the large-scale synthesis of precursors,such as short carbon chains(polyynes),and regulation technology for the transport of reactants in one-dimensional space.Here,we report a facile method for the rapid preparation of polyynes in large quantities using a commercial laser marking machine.Spectroscopic characterizations show that a large number of polyynes,such as C_(8)H_(2),C_(10)H_(2),C_(12)H_(2),and C_(14)H_(2),can be produced by ablating the graphite plate immersed in the organic liquid using a laser marking machine.The results of in situ Raman spectroscopy investigation of C_(2n)H_(2)-filled single-walled carbon nanotubes further confirm that a variety of polyyne molecules are synthesized.Meanwhile,in situ Raman spectroscopy also shows that the local heating treatment can accelerate the filling process of C_(2n)H_(2)into one-dimensional channels.This work provides new insights into the study of linear carbon chains and space-confined synthesis methods.
基金supported by the National Basic Research Program of China(2012CB922001)the National Natural Science Foundation of China(51072193)the Fundamental Research Funds for the Central Universities(WK2060140014)
文摘New Aurivillius phase Bi9Fe4.7Me0.3Ti3O27(Me = Fe, Co, Ni, Mn) oxides have been prepared using a citrate combustion method. X-ray diffraction on powders and high-resolution transmission electron microscopy investigation confirmed that the Bi9Fe4.7Me0.3Ti3O27 samples are with an eight-layer structure. Both ferromagnetic and ferroelectric investigations suggested that Co or Ni substitution could enhance their multiferroic properties,while Mn substitution depressed them. Among all the samples, Bi9Fe4.7Co0.3Ti3O27 sample exhibits the largest remnant polarization of Pr*3.8 l C/cm2, and the largest remnant magnetization of Mr*0.06 lB/f.u. with a Curie temperature about 764 K, while the Bi9Fe4.7Ni0.3Ti3O27 sample has the largest spontaneous magnetization(0.26 lB/f.u.). The improved ferromagnetic properties ofboth Bi9Fe4.7Co0.3Ti3O27 and Bi9Fe4.7Ni0.3Ti3O27 can be ascribed to the spin canting of magnetic ion-based sublattices via the Dzyaloshinskii–Moriya interaction and also the magnetic ions exchanging interactions(Fe3–O–Co3or Fe3–O–Ni3).
