Home > News >

Advanced Functional Materials:MOF High rate sodium ion battery by in situ growth of FEP quantum dots

wallpapers News 2020-09-20
With the development of science technology

requires higher higher battery performance in various fields the main factor affecting battery performance depends on electrode materials. In recent years the development of new anode materials with low cost high energy density long cycle life has become the focus of research. Transition metal phosphides (tmps) have high theoretical sodium storage capacity but their low conductivity volume expansion after sodium intercalation / removal lead to poor rate performance. It is considered that the effective way to solve the above problems is to composite tmps with carbon materials or reduce their characteristic size. However surface controlled capacitive behavior is generally dominant in the contribution of battery capacity which inevitably leads to the loss of charge discharge platform the reduction of the working potential window of the whole battery structure. However this problem has attracted little attention.

recently Professor Zhao Yufeng's team used the porous structure formed by self-assembly between metal ions (atoms) organic ligs in metal organic frameworks (MOF) materials to confine FEP quantum dots to p-doped three-dimensional octahedral carbon frameworks / carbon nanotubes by one-step carbonization / phosphating method( FeP@OCF )。 This self limiting growth method not only reduces the size of FEP nanoparticles shortens the ion transport path improves the rate performance of the material but also effectively alleviates the agglomeration effect of FEP particles in the growth process avoids the problem of electrode material pulverization caused by large volume expansion in the charge discharge process thus enhancing the stability of the material. At the same time in the process of synthesis of MOF the introduction of nitrogen doped carbon nanotubes constructs a three-dimensional conductive network structure which improves the conductivity of the composite accelerates the electron / ion transport improves the cycle rate performance of the whole material. Therefore the reversible capacity of 647 MAH g-1 can be achieved at a current density of 0.1 A g-1 even at a high current density of 20 a g-1 the capacity can still reach 224 MAH g-1 showing ultra-high rate performance. Compared with pure FEP FeP@OCF The capacity of the material in both platform area slope area is significantly improved. In addition by in situ transmission electron microscopy we observed in real time FeP@OCF There is no obvious volume expansion phenomenon in the charging process which is further confirmed by the analysis of in-situ selected area diffraction electron image data FeP@OCF The intercalation / conversion reaction mechanism of sodium ions. be based on FeP@OCF We used na3v2 (PO4) 3 as cathode material FeP@OCF The results show that the energy density of 184 whkg-1 can be achieved at 227 wkg-1 power density FeP@OCF Potential application value.

the three-dimensional octahedral carbon skeleton / carbon nanotube materials with FEP quantum dots confined by MOF confinement are designed in this work which show excellent rate performance in sodium ion half cell achieve high energy density in full cell test. This work provides a new way for the design practical application of phosphide full cell.

TRUNNANO (aka. Luoyang Tongrun Nano Technology Co. Ltd.) is a trusted global chemical material supplier & manufacturer with over 12 years' experience in providing super high-quality chemicals and Nanomaterials. Our company has successfully developed a series of powder materials (including oxides, carbides, nitrides, single metal, etc.), high-purity targets, functional ceramics, and structural devices. OEM service is available. Please contact us if necessary.