| Layered double hydroxides?LDHs?are typical inorganic layered materials.The metal ions on the plate can be exchanged without changing the structure of the plate,the metal ions are highly dispersed on the plate,and the anions between the plates can also be replaced to adjust the distance between the plates and the corresponding chemical properties.These characteristics makes LDH has a wide range of applications in electrocatalysis,adsorption,biosensing,energy storage.Although great progress has been made in the application and development of LDH,the practical application of LDH in the field of electrochemical energy storage and sensing is mainly limited by the low conductivity.In order to solve this problem,LDH/carbon nanocomposites with high charge flow and high specific surface area have been synthesized for high efficiency electrode materials.In this study,we first prepared LDH with different metal components.By adjusting the types of metal cations on the laminate,the synergistic effect of different active metal ions on the physicochemical and capacitive properties of LDH was studied.The substitution of Al3+by different kinds of metal ions can effectively reduce the bandgap energy of the double active metal LDH and make the redox reaction of the sample easier.NiMn-LDH has the highest specific capacitance(1322F·g-1),good rate performance and high energy density(79.3 Wh·kg-1)in all the samples.The conductivity is increased due to the low bandgap energy Morphology is well maintained.Indicating that NiMn-LDH has the best energy storage performance in a series of multi-active metal components LDH.Furthermore,the application of three-dimensional carbon foam/LDH/graphene composites in the sensing field is studied.The carbon foam is an independent three-dimensional porous material.The double active metal component LDH grown on the sponge serves as a glucose sensing electrode material.The presence of a carbon sponge not only serves as a growth base for LDH,but also allows LDH to grow vertically on its surface to prevent its stacking,and it also greatly enhances the electrical conductivity.A small amount of graphene is coated on the surface of the LDH layer to connect adjacent LDH nanosheets.So as to further improve the conductivity and enhance the mechanical strength.By comparison of various metal components LDH,NiMn-LDH/SC/GO has the best glucose sensing sensitivity,strong anti-interference performance and the widest measurement range,which is of great guiding significance for the preparation of new and efficient glucose sensors. |
PDF Full Text Request