Synthesis and characterization of hybrid fluorescent superparamagnetic core-shell particles of Fe@C-CNx composition are presented for the first time. The prepared Fe@C-CNx hybrid nanoparticles were found to possess mu...Synthesis and characterization of hybrid fluorescent superparamagnetic core-shell particles of Fe@C-CNx composition are presented for the first time. The prepared Fe@C-CNx hybrid nanoparticles were found to possess multifunctionality by exhibiting strong superparamagnetic properties and bright fluorescence emissions at 500 nm after the excitation with light in the UV-visible range. Fe@C-CNx also exhibits photocatalytic activities for organic dye degradation comparable to pure amorphous CNx with reusability through magnetic separation. The combination of magnetic and fluorescent properties of core-shell Fe@C-CNx nanoparticles opens opportunities for their application as sensors and magnet manipulated reusable photocatalysts. Superparamagnetic Fe@C core-shell nanoparticles were used as the template material in the synthesis, where the carbon shell was functionalized through one-step free-radical addition of alkyl groups terminated with carboxylic acid moieties. The method utilizes the organic acyl peroxide of dicarboxylic acid (succinic acid peroxide) as a non-oxidant functional free radical precursor for functionalization. Further, covalently functionalized succinyl-Fe@C core-shell nanoparticles were coated with the amorphous carbon nitride (CNx) generated by an in-situ solution-based chemical reaction of cyanuric chloride with lithium nitride. A detailed physicochemical characterization of the microstructure, magnetic and fluorescence properties of the synthesized hybrid nanoparticles is provided.展开更多
α-AlH_(3)is regarded as one of the most promising hydrogen storage materials due to its high hydrogen storage capacity(10.1 wt.%,148 kg·m^(-3)).However,in practical applications,the associated hydrogen release t...α-AlH_(3)is regarded as one of the most promising hydrogen storage materials due to its high hydrogen storage capacity(10.1 wt.%,148 kg·m^(-3)).However,in practical applications,the associated hydrogen release temperature remains relatively high.To effectively address this issue,hollow structured Fe@C nanorods derived from Fe-MOF are introduced as highly efficient catalyst to optimize the dehydrogenation properties ofα-AlH_(3).Comparatively,the initial hydrogen release temperature ofα-AlH_(3)+3 wt.%Fe@C is reduced to 94.2℃,which is significantly lower than that of pureα-AlH_(3)(137.8℃).At 100 and 120℃,it exhibits hydrogen capacities of 5.38 wt.%and 7.47 wt.%,respectively,whereas pureα-AlH_(3)only delivers hydrogen capacities of 0.24 wt.%and 5.94 wt.%under the same temperatures.The density functional theory(DFT)calculations further indicate that the existence of Fe@C catalyst can make the length of Al-H bond increase,which is more conducive to the release of hydrogen.The results show that the synergistic effect of Fe and porous carbon in Fe@C nanorods can improve the hydrogen desorption kinetics ofα-AlH_(3),providing a good prospect for the application ofα-AlH_(3)in hydrogen storage fields.展开更多
The generalized gradient approximation （GGA） based on density functional theory （DFT） was used to analyze the structural and electronic properties of Fe@C60 and C59Fe for comparison. Among the six possible optimiz...The generalized gradient approximation （GGA） based on density functional theory （DFT） was used to analyze the structural and electronic properties of Fe@C60 and C59Fe for comparison. Among the six possible optimized geometries of Fe@C60, the most favorable endohedral site of Fe atom is under the center of a hexagon ring, i.e., Fe@C60-6. The Energy gap （Eg） of Fe@C60-6 is smaller than those of C59Fe and C60, indicating the higher chemical reactivity. The magnetic moment of Fe atom in Fe@C60-6 is preserved to some extent though there is the hybridization between the ge atom and C atoms of the cage, in contrast to the completely quenched magnetic moment of the Fe atom in C59Fe.展开更多
文摘Synthesis and characterization of hybrid fluorescent superparamagnetic core-shell particles of Fe@C-CNx composition are presented for the first time. The prepared Fe@C-CNx hybrid nanoparticles were found to possess multifunctionality by exhibiting strong superparamagnetic properties and bright fluorescence emissions at 500 nm after the excitation with light in the UV-visible range. Fe@C-CNx also exhibits photocatalytic activities for organic dye degradation comparable to pure amorphous CNx with reusability through magnetic separation. The combination of magnetic and fluorescent properties of core-shell Fe@C-CNx nanoparticles opens opportunities for their application as sensors and magnet manipulated reusable photocatalysts. Superparamagnetic Fe@C core-shell nanoparticles were used as the template material in the synthesis, where the carbon shell was functionalized through one-step free-radical addition of alkyl groups terminated with carboxylic acid moieties. The method utilizes the organic acyl peroxide of dicarboxylic acid (succinic acid peroxide) as a non-oxidant functional free radical precursor for functionalization. Further, covalently functionalized succinyl-Fe@C core-shell nanoparticles were coated with the amorphous carbon nitride (CNx) generated by an in-situ solution-based chemical reaction of cyanuric chloride with lithium nitride. A detailed physicochemical characterization of the microstructure, magnetic and fluorescence properties of the synthesized hybrid nanoparticles is provided.
基金supported by the Key R&D projects of Jilin Provincial Science and Technology Development Plan(Nos.20230201140GX and 20230201125GX)the National Key Research and Development Program of China(No.2021YFB4000604)+4 种基金the Youth Innovation Promotion Association CAS(No.2022225)the Youth Growth science and technology Plan project of Jilin Province Science and Technology Development Plan(No.20220508001RC)the Independent Research Project of the State Key Laboratory of Rare Earth Resources Utilization(No.110000RL86)the Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,the National Natural Science Foundation of China(No.22103010)the Natural Science Foundation of Shandong Province(No.ZR2021QB104).
文摘α-AlH_(3)is regarded as one of the most promising hydrogen storage materials due to its high hydrogen storage capacity(10.1 wt.%,148 kg·m^(-3)).However,in practical applications,the associated hydrogen release temperature remains relatively high.To effectively address this issue,hollow structured Fe@C nanorods derived from Fe-MOF are introduced as highly efficient catalyst to optimize the dehydrogenation properties ofα-AlH_(3).Comparatively,the initial hydrogen release temperature ofα-AlH_(3)+3 wt.%Fe@C is reduced to 94.2℃,which is significantly lower than that of pureα-AlH_(3)(137.8℃).At 100 and 120℃,it exhibits hydrogen capacities of 5.38 wt.%and 7.47 wt.%,respectively,whereas pureα-AlH_(3)only delivers hydrogen capacities of 0.24 wt.%and 5.94 wt.%under the same temperatures.The density functional theory(DFT)calculations further indicate that the existence of Fe@C catalyst can make the length of Al-H bond increase,which is more conducive to the release of hydrogen.The results show that the synergistic effect of Fe and porous carbon in Fe@C nanorods can improve the hydrogen desorption kinetics ofα-AlH_(3),providing a good prospect for the application ofα-AlH_(3)in hydrogen storage fields.
基金Project supported by the National Natural Science Foundation of China （No. 10174039） and Jiangsu Natural Science Foundation （No. BK2002099）. Dedicated to Professor Xikui Jiang on the occasion of his 80th birthday.
文摘The generalized gradient approximation （GGA） based on density functional theory （DFT） was used to analyze the structural and electronic properties of Fe@C60 and C59Fe for comparison. Among the six possible optimized geometries of Fe@C60, the most favorable endohedral site of Fe atom is under the center of a hexagon ring, i.e., Fe@C60-6. The Energy gap （Eg） of Fe@C60-6 is smaller than those of C59Fe and C60, indicating the higher chemical reactivity. The magnetic moment of Fe atom in Fe@C60-6 is preserved to some extent though there is the hybridization between the ge atom and C atoms of the cage, in contrast to the completely quenched magnetic moment of the Fe atom in C59Fe.
