Hnub ci vaj huam sib luag, tseem hu ua "solar chips" lossis "photocells" thiab "solar cells", yog photoelectric semiconductor nplooj ntawv uas siv lub hnub ci teeb ncaj qha los tsim hluav taws xob. Ib lub cuab yeej uas ncaj qha hloov lub hnub ci lub zog rau hauv hluav taws xob los ntawm cov nyhuv photoelectric lossis photochemical nyhuv. Nyob rau hauv physics, nws yog hu ua photovoltaic (Photovoltaic, abbreviated li PV), los yog photovoltaic luv luv. Ib lub hnub ci vaj huam sib luag tsis tuaj yeem siv ncaj qha los ua lub zog hluav taws xob. Txhawm rau siv los ua lub zog siv hluav taws xob, ntau lub hnub ci ib leeg yuav tsum tau txuas nrog hauv cov koob thiab sib luag thiab nruj nreem kaw rau hauv cov khoom sib txuas. Nws txoj hauv kev ua haujlwm tsuas yog tias lub hnub ci vaj huam sib luag nqus lub hnub ci lub zog thaum nruab hnub thiab hloov mus rau hauv hluav taws xob thiab khaws cia rau hauv lub roj teeb, thiab lub roj teeb siv lub hnub ci txoj kev teeb pom kev thaum hmo ntuj. Yog li vim li cas cov hnub ci vaj huam sib luag tsim hluav taws xob hauv tshav ntuj?
Hnub ci vaj huam sib luag feem ntau siv cov khoom siv uas teb rau lub teeb thiab tuaj yeem hloov lub hnub ci lub zog rau hauv hluav taws xob. Cov khoom siv feem ntau yog silicon, uas yog ib qho ntawm cov khoom siv ntau tshaj plaws hauv ntiaj teb. Nws muaj cov yam ntxwv semiconductor, uas nteg lub hauv paus rau cov txheej txheem hloov dua siab tshiab ntawm cov hnub ci.
Tab sis thawj yam uas yuav tsum tau to taub yog tias cov conductivity ntawm ntshiab silicon yog heev tsis zoo, thiab tsis muaj electrons uas yuav txav tau dawb do nyob rau hauv lub crystal qauv. Txhawm rau txhim kho nws cov conductivity, ntshiab silicon feem ntau yog doped nrog cov kab impurities los txhim kho nws cov conductivity. Raws li cov yam ntxwv no, cov khoom siv hluav taws xob sib txawv tuaj yeem ua tau.
Rau cov silicon siv los ua lub hnub ci vaj huam sib luag ntawm hnub ci zog txoj kev teeb, phosphorus lossis boron feem ntau yog ntxiv. Thaum boron ntxiv, silicon crystal yuav tsim ib lub qhov. Vim hais tias tus thawj silicon atom yog ib puag ncig los ntawm 4 electrons, thiab lub boron atom yog surrounded los ntawm tsuas yog 3 electrons, lub qhov yuav tsum generated thaum nws yog doped rau hauv thawj crystal qauv. Yog tsis muaj electrons, lub qhov no tsis ruaj khov heev thiab yooj yim absorbs lwm electrons los ua ib tug P-hom semiconductor.
Thaum phosphorus impurities yog doped rau hauv silicon crystals, vim hais tias muaj 5 electrons nyob ib ncig ntawm lub phosphorus atoms, cov electron ntxiv yuav muaj zog heev, tsim N-hom semiconductor. Muaj ntau qhov hauv P-hom semiconductors, thiab muaj ntau yam dawb electrons hauv N-hom semiconductors. Thaum ob qhov kev sib cuag, cov hluav taws xob dawb no yuav pom qhov thiab sau lawv. Qhov chaw sib cuag ntawm ob yuav tsim qhov sib txawv, uas yog, PN kev sib tshuam. P-hom sab yog qhov zoo thiab tsis zoo, thiab sab N-hom yog qhov zoo.
Thaum lub teeb tau txais, lub zog muaj nyob hauv lub teeb yuav raug xa mus rau lub semiconductor. Lub zog no yuav xoob cov qauv ntawm cov electrons thiab txav mus los ywj pheej. Qhov no yog vim lub hnub ci zog lub zog yuav sib cais electrons thiab qhov. Raws li qhov xwm txheej ib txwm muaj, photon nrog qee lub zog yuav tso tawm cov hluav taws xob, uas tsuas yog tshwm sim los tsim lub qhov dawb. Yog tias qhov no tshwm sim tsuas yog nyob ze ntawm qhov chaw sib cuag, thiab thaum nyiam los ntawm qhov chaw tsim hluav taws xob, cov khoom siv hluav taws xob yuav ntws mus rau hauv n cheeb tsam, thiab qhov yuav ntws mus rau hauv P cheeb tsam, tsim ib qho tam sim no los ntawm N-hom cheeb tsam mus rau P- hom tsam. Lub zog cog ntawm lub roj teeb yog tsim. Hluav taws xob yog tsim los ntawm qhov hluav taws xob, uas yog siv rau kev them nyiaj.
Txawm li cas los xij, nws yuav tsum tau muab sau tseg tias semiconductors tsis zoo conductors ntawm hluav taws xob, thiab electrons ntws los ntawm PN hlws ris thiab ces ntws nyob rau hauv lub semiconductor, uas yuav ua rau ntau poob. Yog li ntawd, txheej sab sauv feem ntau yog coated nrog hlau. Txawm li cas los xij, yog tias nws tau pleev xim tag nrho, nws yuav ua rau lub hnub ci tsis dhau. Raws li ib txwm muaj, daim phiaj hlau yog siv los npog PN kev sib tshuam. Lwm qhov yuav tsum tau nco ntsoov yog tias qhov saum npoo ntawm silicon yog qhov zoo heev. Yog tias tsis kho, lub hnub ci ntau yuav tshwm sim. Txhawm rau daws qhov teeb meem no, cov chaw tsim hluav taws xob hnub ci txoj kev teeb pom kev zoo feem ntau yuav ntxiv ib txheej ntawm kev tiv thaiv zaj duab xis uas tsis tshua muaj kev cuam tshuam coefficient ntawm lub hnub ci vaj huam sib luag. Qhov poob los ntawm kev xav yuav raug tswj tsis pub dhau 5 feem pua.
