Cov hluav taws xob conductivity thiab thermal conductivity ntawm graphite electrodes yog dab tsi?

Cov electrodes graphite ua tau zoo heev hauv kev ua hluav taws xob thiab kev ua kom sov, feem ntau yog vim lawv cov qauv siv lead ua thiab cov yam ntxwv ntawm kev faib hluav taws xob. Nov yog kev tshuaj xyuas ntxaws ntxaws:

1. Kev Ua Hluav Taws Xob: Zoo heev thiab Anisotropic
   Qhov Chaw ntawm Kev Ua Haujlwm Siab:
   Txhua lub atom carbon hauv graphite tsim cov kev sib txuas covalent los ntawm sp² hybridization, nrog rau ib qho p electron seem tsim cov delocalized π bonds (zoo ib yam li cov electrons dawb hauv cov hlau). Cov electrons dawb no tuaj yeem txav mus los tau yooj yim thoob plaws hauv lub crystal, ua rau graphite muaj cov conductivity zoo li hlau.
   Kev Ua Haujlwm Anisotropic:

• Kev Taw Qhia Hauv Dav Hlau: Kev tiv thaiv tsawg kawg nkaus rau kev tsiv teb tsaws chaw ntawm cov hluav taws xob ua rau muaj kev coj ua siab heev (kev tiv thaiv kwv yees li 10⁻⁴ Ω·cm, ze rau ntawm tooj liab).
• Kev Taw Qhia Ntawm Cov Txheej Txheem: Kev hloov pauv ntawm cov electron vam khom rau cov zog van der Waals, ua rau txo qis kev coj ua hluav taws xob (kev tiv taus siab txog 100 npaug ntau dua li hauv-dav hlau).
  Qhov Tseem Ceeb ntawm Daim Ntawv Thov: Hauv kev tsim electrode, txoj kev sib kis tam sim no tuaj yeem ua kom zoo dua los ntawm kev taw qhia cov graphite flakes kom txo qis kev poob zog.
  Kev Sib Piv Nrog Lwm Cov Khoom Siv:
• Sib dua li cov hlau (piv txwv li, tooj liab), nrog rau qhov ceev tsuas yog 1/4 ntawm tooj liab, ua rau nws tsim nyog rau cov ntawv thov uas muaj qhov hnyav (piv txwv li, aerospace).
• Kev tiv taus kub siab dua piv rau cov hlau (graphite muaj qhov melting ntawm ~ 3650 ° C), tswj kev ua haujlwm ruaj khov hauv qab qhov kub heev.

2. Kev Ua Thermal Conductivity: Zoo thiab Anisotropic
   Qhov Chaw Uas Muaj Kev Ua Haujlwm Thermal Siab:

• Kev Taw Qhia Hauv Dav Hlau: Cov kev sib txuas lus sib xyaw ua ke ntawm cov pa roj carbon ua rau muaj kev nthuav dav ntawm cov phonons (lattice vibrations), nrog rau kev ua kom sov ntawm 1500–2000 W/(m·K), yuav luag tsib npaug ntawm tooj liab (401 W/(m·K)).
• Kev Taw Qhia Ntawm Cov Txheej Txheem: Kev ua kom sov poob qis mus txog ~ 10 W / (m · K), qis dua 100 npaug dua li hauv-dav hlau.
  Cov txiaj ntsig ntawm daim ntawv thov:
• Kev Tshem Kub Sai: Hauv cov chaw kub siab xws li cov cub hluav taws xob arc thiab cov cub hluav taws xob ua hlau, cov hluav taws xob graphite hloov pauv cua sov mus rau cov tshuab txias, tiv thaiv kev kub hnyiab thiab kev puas tsuaj hauv zos.
• Kev Ruaj Ntseg Thermal: Kev ua tau zoo ntawm cov cua sov tas li ntawm qhov kub siab txo cov kev pheej hmoo ntawm kev puas tsuaj ntawm cov qauv uas tshwm sim los ntawm kev nthuav dav thermal.

3. Kev Ua Haujlwm Zoo thiab Cov Ntawv Thov Ib Txwm Muaj
   Hluav Taws Xob Arc Rauv Hlau Ua:
   Cov hluav taws xob graphite yuav tsum tiv taus qhov kub thiab txias heev (>3000°C), cov dej ntws siab (kaum tawm txhiab tus amperes), thiab kev ntxhov siab ntawm lub tshuab. Lawv cov hluav taws xob conductivity siab ua kom muaj kev hloov pauv zog mus rau qhov them, thaum lawv cov thermal conductivity tiv thaiv cov hluav taws xob yaj lossis tawg.
   Cov Anodes ntawm Lithium-Ion Battery:
   Cov qauv graphite uas muaj ntau txheej ua rau cov lithium ions sib xyaw ua ke sai sai/tsis sib xyaw ua ke sai sai, thaum cov electron conduction hauv dav hlau txhawb nqa kev them thiab tso tawm sai.
   Kev Lag Luam Semiconductor:
   Cov graphite uas muaj purity siab yog siv rau hauv cov cub tawg uas muaj ib lub siv lead ua silicon, qhov twg nws cov thermal conductivity ua rau muaj kev tswj qhov kub thiab txias sib xws thiab nws cov hluav taws xob conductivity ua rau cov cua sov ruaj khov.

4. Cov Tswv Yim Txhim Kho Kev Ua Haujlwm
   Kev Hloov Kho Khoom Siv:

• Ntxiv cov carbon fibers lossis nanoparticles ua rau cov isotropic conductivity zoo dua.
• Cov txheej txheem saum npoo (piv txwv li, boron nitride) txhim kho kev tiv thaiv oxidation, ua kom lub neej ua haujlwm ntev dua ntawm qhov kub siab.
  Kev Tsim Qauv:
• Kev tswj cov graphite flake orientation ntawm extrusion lossis isostatic pressing ua rau qhov zoo tshaj plaws conductivity / thermal conductivity hauv cov lus qhia tshwj xeeb.

Kev Txheeb Xyuas:
Cov electrodes graphite yog qhov tseem ceeb hauv electrochemistry, metallurgy, thiab lub zog vim lawv cov hluav taws xob thiab thermal conductivity siab heev hauv-dav hlau, nrog rau kev tiv taus kub siab thiab kev tiv taus corrosion. Lawv cov khoom anisotropic xav tau kev hloov kho qauv tsim kom siv lossis them rau kev hloov pauv ntawm kev ua haujlwm.