Graphene(rGO)based hybrid materials exhibiting electrical conductivity and spin crossover(SCO)behavior are reported.The non-conductive[Fe(qnal)_(2)]_(n)GO(1·GO)and[Fe(qsal)_(2)]_(n)GO(2·GO)hybrids have been ...Graphene(rGO)based hybrid materials exhibiting electrical conductivity and spin crossover(SCO)behavior are reported.The non-conductive[Fe(qnal)_(2)]_(n)GO(1·GO)and[Fe(qsal)_(2)]_(n)GO(2·GO)hybrids have been prepared by employing the electrostatic interaction between the negatively charged graphene oxide(GO)nanosheet and the respective iron(III)complex cations in[Fe(qnal)_(2)]^(+)Cl^(−)and[Fe(qsal)_(2)]^(+)Cl^(−).展开更多
The preparation of uniform and well-dispersed catalysts is crucially important for the controlled growth of single-walled carbon nanotubes(SWCNTs)on substrates.We used graphene oxide(GO)as a support to prepare well-di...The preparation of uniform and well-dispersed catalysts is crucially important for the controlled growth of single-walled carbon nanotubes(SWCNTs)on substrates.We used graphene oxide(GO)as a support to prepare well-dispersed CoWO_(4)nanoparticles with a narrow diameter distribution.When using GO-supported CoWO_(4)as the catalyst precursor and performing the SWCNT growth under the optimized chemical vapor deposition conditions,we realized the diameter-controlled growth of SWCNTs with the mean size of 1.74±0.18 nm.CoWO_(4)is a superior catalyst precursor that can be used to obtain catalyst nanoparticles with a well-controlled size.GO shows to be a feasible substrate,presenting oxygen-containing groups which act as both the binding sites to facilitate the formation of uniform nanoparticles and hydrophilic groups to ensure a good dispersibility in aqueous solution.This strategy may find wide applications in the preparation of various functional nanomaterials.展开更多
We perform detailed quantum chemical calculations to elucidate the origin and mechanism of the selective permeability of alkali and alkaline earth cation- decorated graphene oxide （M-GO） membranes to organic solvent...We perform detailed quantum chemical calculations to elucidate the origin and mechanism of the selective permeability of alkali and alkaline earth cation- decorated graphene oxide （M-GO） membranes to organic solvents. The results show that the selectivity is associated mainly with the transport properties of solvents in the membranes, which depends on two regions of the flow path： the sp3 C-O matrix of the GO sheets and the cation at the center of the hexagon rather than the sp~ region. According to the delocalization of ~ states in sp2 regions, we propose a design guide for high-quality M-GO membranes. The solvent-cation interaction essentially causes directional transport of molecules in the M-GO membranes under the transmembrane pressure, indicating a site-to-site mech- anism. The solvent-sp3 C-O matrix interaction may inhibit molecular transport between two fixed cations by consuming energy. The competition between energy consumption by the solvent-cation interaction and energy expenditure by the solvent-sp3 C-O matrix interaction leads to various transport properties of solvents and thus allows for the selective permeability of the M-GO membranes. Findings from the study are helpful for the future design of multifunctional M-GO macro-membranes as cost-effective solution nanofilters in chemical, biological, and medical applications展开更多
基金supported by KAKENHI Grant-in-Aid for Scientific Research(B)26288026Grant-in-Aid for Scientific Research on Innovative Areas 2506[Science of Atomic Layers].
文摘Graphene(rGO)based hybrid materials exhibiting electrical conductivity and spin crossover(SCO)behavior are reported.The non-conductive[Fe(qnal)_(2)]_(n)GO(1·GO)and[Fe(qsal)_(2)]_(n)GO(2·GO)hybrids have been prepared by employing the electrostatic interaction between the negatively charged graphene oxide(GO)nanosheet and the respective iron(III)complex cations in[Fe(qnal)_(2)]^(+)Cl^(−)and[Fe(qsal)_(2)]^(+)Cl^(−).
基金supported by the Ministry of Science and Technology of China(2016YFA0201904)the National Natural Science Foundation of China(21631002)+2 种基金the Beijing National Laboratory for Molecular Sciences(BNLMS-CXTD-202001)the Shenzhen Basic Research Project(JCYJ20170817113121505)the Shenzhen KQTD Project(KQTD20180411143400981).
文摘The preparation of uniform and well-dispersed catalysts is crucially important for the controlled growth of single-walled carbon nanotubes(SWCNTs)on substrates.We used graphene oxide(GO)as a support to prepare well-dispersed CoWO_(4)nanoparticles with a narrow diameter distribution.When using GO-supported CoWO_(4)as the catalyst precursor and performing the SWCNT growth under the optimized chemical vapor deposition conditions,we realized the diameter-controlled growth of SWCNTs with the mean size of 1.74±0.18 nm.CoWO_(4)is a superior catalyst precursor that can be used to obtain catalyst nanoparticles with a well-controlled size.GO shows to be a feasible substrate,presenting oxygen-containing groups which act as both the binding sites to facilitate the formation of uniform nanoparticles and hydrophilic groups to ensure a good dispersibility in aqueous solution.This strategy may find wide applications in the preparation of various functional nanomaterials.
文摘We perform detailed quantum chemical calculations to elucidate the origin and mechanism of the selective permeability of alkali and alkaline earth cation- decorated graphene oxide （M-GO） membranes to organic solvents. The results show that the selectivity is associated mainly with the transport properties of solvents in the membranes, which depends on two regions of the flow path： the sp3 C-O matrix of the GO sheets and the cation at the center of the hexagon rather than the sp~ region. According to the delocalization of ~ states in sp2 regions, we propose a design guide for high-quality M-GO membranes. The solvent-cation interaction essentially causes directional transport of molecules in the M-GO membranes under the transmembrane pressure, indicating a site-to-site mech- anism. The solvent-sp3 C-O matrix interaction may inhibit molecular transport between two fixed cations by consuming energy. The competition between energy consumption by the solvent-cation interaction and energy expenditure by the solvent-sp3 C-O matrix interaction leads to various transport properties of solvents and thus allows for the selective permeability of the M-GO membranes. Findings from the study are helpful for the future design of multifunctional M-GO macro-membranes as cost-effective solution nanofilters in chemical, biological, and medical applications
