The Preparation Of Heteroatom Doped Nanocarbon Structure Through The Method Of Layered Hydroxides Precursor And Its Electrochemical Evolution

Lithium ion battery (LIBs), Sodium ion battery (SIBs) and Supercapacitor (SC) are one of the most promising energy storage devices which various research efforts for rechargeable batteries have been mainly concentrated on electrode materials for LIBs and SIBs since the 21st century. In terms of the graphite, which as the commercial anode material, there are some advantages existed in graphite such as light weight, easier available and environment friendly, however, the specific capacity, volume density and power density cannot meet the increasing requirements, in particular, mini portable electronic devices, electric vehicles (EVs) and smart grid. Similarly, because of supercapacitor owns the same application in the view of the practical industry, searching for some candidates materials which possess high specific capacity is the key of the development of the supercapacitor. In this regard, as far as we are concerned, exploring some alternative anode materials in which possess higher specific surface area, suitable porous distribution and enhanced electrical conductibility to replace the graphite electrode. Because of those chemical parameters are indeed vital for the promotion of the specific capacity, the enhanced diffusion abilities of electronic and ion as well as the shorten transmission path of the ion during the cycling process. Nowadays, hydrotalcite and hydrotalcite-like precursor have been the most interesting candidate materials in the aspect of the electrochemistry. In this work, we use various of commercial surfactants intercalated CoFeAl-LDH and NiAl-LDH as the precursor to obtain different types of heteroatom doped carbon which as anode electrode in the alkali metal energy devices and supercapacitor, the results demonstrated that those alternative product could exhibit high energy capacities and durability when compared with the commercial graphite electrode. The merits of this work are as followings:(1) Taking advantage of the separate nucleation and aging steps (SNAS) method as the mainly procedure to obtain the CoFeAl-LDH precursor and then mixed with the Melamine in a mortar, upon the calcination and subsequently by acid etching process, the Nitrogen doped amorphous nanocarbon (NAC) has been obtained. With the help of the heteroatom of N, this NAC electrode shows promoted electroconductivity, suitable porous distribution and specific surface area when compared with the traditional non doped carbon. After the evaluation of this anode material, its high performance explain the reason why the layered double hydroxide could enhance the ability in the alkali metal batteries. Similarly, the N doped amorphous carbon exhibits a higher performance in the view of the supercapacitor.(2) We described a preparation of sulfur doped, mesoporous, amorphous carbon (SMAC) from a commercially available alkyl surfactant sulfonate anion intercalated NiAl-LDH precursor via thermal decomposition and subsequent acid leaching. The resulting electrode combines the advantages of facilitating the following electrochemical performances, such as intrinsic doping of sulfur, highly specific area and suitable mesoporous size distribution. The electrochemical performance of the SMAC electrode was also examined for application in LIBs and SIBs compared with the non-doped carbon electrode and hard carbon, etc. The results may provide a clue for producing low cost anode material for industrial applications.