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characterization - Coggle Diagram
characterization
XRD
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to check crystallinity, sample purity, crystal structure by Rietveld refinement, make textural measurements
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BET
higher SA, higher pore volume=higher electrochemical performance=provide more active sites & shorten transporting path of ions in electron
larger SSA& moderate mesoporous size features, contribute to fast ion migration/diffusion during redox reaction.
SSA: measured using BET method (m^2/g), V: usually determined by the amount of adsorbate gas that the material can hold (cm^3/g), D=4V/SSA (nm)@ mean pore diameter: derived from the assumption that the pores are cylindrical/ slit-like in shape and uniformly distributed
interpretation: 1) increase in SSA& decrease in volume= small pores, microporous (pore diameter < 2nm), 2) increase in SSA & increase in volume= mixture of small& large pores, mesoporous (pore diameter~2-50nm), 3) decrease in SSA&increase in volume= larger pores, macroporous (pore diameter> 50nm)
energy storage: in SCs& batteries, increase SSA & optimal pore sizes facilitate ion transport & increase charge storage capacity.
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HR-TEM & SAED
lattice fringes with lattice spacing corresponded to hkl=confirm the formation of crystalline & consistent XRD pattern
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