Tunable pore structure of Carbide Derived Carbon using accurate control of TiC solid solution

Abstract

Novel precursor, titanium solid solution carbide, was produced for the synthesis of carbide derived carbon (CDC) which has variety of applications such as supercapacitor, catalyst support, or adsorbents for gases like hydrogen, methane or separation of CO2 gas. All these applications are possible due to its tunable pore characteristics with experimental parameters. First, we can successfully synthesize and control accurate composition of solid solution precursor such as (Ti1-xMex)C and Ti(C1-xAx) by high energy ball milling. Second, with selection of the substitutional atom (A), it could be possible to change specific dimension of pore volumes which can be covered in the range of micropore (<2nm) or mesopore size (2nm-50nm). Third, properties for hydrogen storage and supercapacitor are analyzed. Finally, Pore structure of carbide derived carbon was successfully designed by chlorination of Ti(C1-xAx)(A= Oxygen or Nitrogen) solid solution phase. Ti(C1-xAx)-CDC has significantly better values of SSA and pore volume than reported before. Ti(C1-xOx)-CDC contains micropore sized pore, in contrast, Ti(C1-xNx)-CDC is dominantly shows formation of mesopore. Thus, characteristic dimensions of mesopore or micropore can be controlled by which kind of substitutional atom instead of carbon in solid solution. One of CDCs have noticeably shows not only 90% (Vmicro/Vtotal) micropore volume fraction up to Ti(C0.7O0.3)CDC: 1.55cm3/g (Vmicro) per 1.72cm3/g (Vtotal), 3200cm2/g (SSA) but also mesopore volume up to Ti(C0.5N0.5) : 3.34cm3/g (Vmeso) per 3.45cm3/g (Vtotal) , 522.1cm2/g (SSA) by selective extraction of titanium. Although (Ti1-xMex)C-CDC didnt show significant difference, its result was used for the basic data for analysis of CDC pore structure with molecular dynamics simulation.