Chlorination of MAX Phase Carbides

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Chlorination of MAX Phase Carbides

• Engineering Nanoporous Carbon

Matt Hoban Mentor Liz Hoffman AdvisorDr. Michel
Barsoum
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The Beginning MAX Phase Carbides and Nitrides

• Ceramics with formula Mn1AXn
• M is an early transition metal
• A is an A group element
• X is either carbon or nitrogen
• First fabricated in bulk and characterized by Dr.
  Barsoum and his research group at Drexel
  University.
• Materials used in current study
• Ta2AlC
• Ti3GeC2
• Ti3SiC2

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MAX Phase Carbides
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Characteristics of MAX Carbides

• Share favorable characteristics of
• both metals and ceramics!
• Good thermal and electrical conductivity
• Low coefficient of thermal expansion
• Resistant to thermal shock
• Highly machinable due to lamellar structure
• Exhibit plastic deformation at high
• temperatures
• High melting point
• Low Density

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The Product CDC

• CDC stands for Carbide Derived Carbon
• Properties
• Conformal
• Nanosized pores
• High Specific Surface Area
• Applications
• Gas Filtration
• Gas Seperation
• Gas Storage
• Supercapacitors

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Producing CDC

• Process
• Purpose of each step
• Machines used
• Time elapsed
• Results received

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Chlorination of MAX Carbides

• Process of Chlorination
• Setup
• Variables
• Result
• Mn1ACn ((n1)xy)/2Cl2nC(n1)MClxACly

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Quantichrome Porosity

• Outgassing
• Purpose
• Removal of Vapors
• Results
• Accurate weight for analysis
• Analysis
• Preparation
• Procedure
• Gases used
• CO2
• N2
• Ar
• Data obtained

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Quantichrome Results
Type IV

• Initial Data
• Varied Braneur Isotherms
• Not extremely significant alone
• Density Functional Theory
• Interprets data
• Introduces artifacts

Type I
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Horriba Particle Size Analysis

• Procedure
• Dispersants
• Refractive index of materials
• Horriba
• How it works
• Angle of diffraction
• Inverse relationship
• Amount of Diffraction
• Direct relationship

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Research to date

• Grain size analysis of Ta2AlC (25 microns) and
  Ge3SiC2 (15 micron) samples
• Particle size analysis of all CDC created
• Mean18-20 micrometers by volume
• Chlorination of bulk and powder Ta2AlC at 400,
  800, and 1200 C
• Pore size distribution for two of the CDC samples
  created thus far

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Plan for the next 4 weeks

• Get data on porosity of all CDC from Ta2AlC
• Determine if particle size is a variable that
  affects pore size distribution
• Chlorinate sub-micrometer particles of Ta2AlC,
• if particle size does in fact influence pore
  size
• Synthesize and chlorinate bulk and powder samples
  of Ti3GeC2, as well as Ti3SiC2

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Acknowledgements

• Dr. Michel Barsoum
• Liz Hoffman
• Adrish Ganguly
• Ranjan Dash
• John Chmiola
• Aiguo Zhou
• Surojit Gupta
• Vadym Muchalin