光伏效應(yīng)及其光電轉(zhuǎn)化理論-馬貴軍課件

光伏效應(yīng)及其光電轉(zhuǎn)化理論報(bào)告人：馬貴軍研究課題：光催化分解硫化氫研究指導(dǎo)教師：李燦研究員SeminarΙ2008年5月27日報(bào)告內(nèi)容概念介紹研究進(jìn)展結(jié)論與展望參考文獻(xiàn)概念介紹1839年:法國科學(xué)家貝克雷爾(Becqurel)發(fā)現(xiàn)，光照能使半導(dǎo)體材料的不同部位之間產(chǎn)生電位差。這種現(xiàn)象后來被稱為“光生伏打效應(yīng)”，簡稱“光伏效應(yīng)”1954年:美國科學(xué)家恰賓和皮爾松在美國貝爾實(shí)驗(yàn)室首次制成了實(shí)用的單晶硅太陽電池(6％)，誕生了將太陽光能轉(zhuǎn)換為電能的實(shí)用光伏發(fā)電技術(shù)。光伏效應(yīng)(Photovoltaiceffect):

指光照使不均勻半導(dǎo)體或半導(dǎo)體與金屬結(jié)合的不同部位之間產(chǎn)生電位差的現(xiàn)象。它首先是由光子（光波）轉(zhuǎn)化為電子、光能量轉(zhuǎn)化為電能量的過程；其次，是形成電壓過程。有了電壓，就像筑高了大壩，如果兩者之間連通，就會(huì)形成電流的回路。e-------------

++++++++++++h+空間電荷區(qū)內(nèi)建電場空穴擴(kuò)散力電子擴(kuò)散力概念介紹―節(jié)P型n型_+ρ(C/cm3)+eNd-eNaxpxpxnxnNaxp=Ndxn概念介紹―節(jié)e-------------

++++++++++++h+P型n型C=；2(Vd-Va).(ε1Na+ε2Nd)qε1ε2NdNa1/C2=_+ρ(C/cm3)+eNd-eNaxpxnVaVa+dVC：電容Vd:內(nèi)建電勢Va:外加電壓ε:介電常數(shù)N：攙雜濃度+dQ-dQdQdVa概念介紹―節(jié)BackandFrontcontact:導(dǎo)出電荷Antireflectioncoating:增加光吸收P-andN-typesemiconductor:產(chǎn)生電荷Coverglass:保護(hù)電極光伏電池基本原理IVDarkLightVocIphIscMaximumPowerpointVmpImpI-Vcurve概念介紹―光伏電池填充因子(FF):電池在不同的負(fù)載條件下，輸出的功率是不一樣的。FF=Pmax/IscVoc,Pmax為最大輸出功率。入射光子到電子的轉(zhuǎn)換效率(IPCE):

IPCE是描述太陽能電池在單色光作用下的轉(zhuǎn)換效率指標(biāo)，定義為：IPCE=轉(zhuǎn)移到外電路的電子數(shù)/入射的光子數(shù)。IPCE的大小決定于：1)光捕獲效率[LHE(λ)],2)電荷注入效率(Φinj),3)電荷收集效率(ηe)。能量轉(zhuǎn)換效率(η):太陽能電池的最大功率輸出與入射光的能量(Plight)之比。幾種最主要的光伏電池TypeofcellEfficiency(%)ResearchandtechnologyneedsCellModuleCrystallinesilicon2410-15Higherproductionyields,loweringofcostandenergycontentMulticrystallinesilicon189-12LowermanufacturingcostandcomplexityAmorphoussilicon137Lowerproductioncosts,increaseproductionvolumeandstabilityCuInSe21912Replaceindium(tooexpensiveandlimitedsupply),ReplaceCdSwindowlayer,scaleupproductionDye-sensitizednanostructuredmaterials10-117Improveefficiencyandhigh-temperaturestability,scaleupproductionBipolarAlGaAs/Siphotoelectrochemicalcell19-20-Reducematerialscost,saleupOrganicsolarcell2-3-ImprovestabilityandefficiencyM.Gr?tzel,Photoelectrochemicalcells,Nature2001(414),338硅基光伏電池AdolfGoetzbergera,ChristopherHeblinga,Hans-WernerSchockPhotovoltaicmaterials,history,statusandoutlook.MaterialsScienceandEngineeringR40(2003)1–46Althoughcrystallinesiliconisnottheoptimalmaterialfromasolidstatephysicspointofviewitdominatesthemarketandwillcontinuetodothisforthenext5–10years.CdTe-CdS光伏電池

AdolfGoetzbergera,ChristopherHeblinga,Hans-WernerSchockPhotovoltaicmaterials,history,statusandoutlookMaterialsScienceandEngineeringR40(2003)1–46Efficiencies:above16%BandgapclosetotheoptimumforsolarenergyconversionEasytohandleinthin-filmdepositionprocessesCd：toxicmaterialThedifficultyofdopingp-typeCdTeThedifficultyintherecombinationlossesassociatedwiththejunctioninterfaceCIGS光伏電池AdolfGoetzbergera,ChristopherHeblinga,Hans-WernerSchockPhotovoltaicmaterials,history,statusandoutlook.MaterialsScienceandEngineeringR40(2003)1–46Efficiencies:11–18%染料敏化光伏電池原理示意圖AdolfGoetzbergera,ChristopherHeblinga,Hans-WernerSchockPhotovoltaicmaterials,history,statusandoutlook.MaterialsScienceandEngineeringR40(2003)1–46Theconductionmechanismisbasedonamajoritycarriertransportasopposedtotheminoritycarriertransportofconventionalinorganiccells.InstabilityoverthetimeandthetemperaturerangewhichoccursunderoutdoorconditionsEfficiencies:7–11%有機(jī)光伏電池ExtremelyhighopticalabsorptioncoefficientsEaseoflarge-scalemanufacturingatlow-temperatureprocessesandverylowcostsThewidthofthechargegenerationlayerismuchsmallerthaninorganiccells.HolgerSpanggaard,FrederikC.Krebs,Abriefhistoryofthedevelopmentoforganicandpolymericphotovoltaics,SolarEnergyMaterials&SolarCells83(2004)125–146AdolfGoetzbergera,ChristopherHeblinga,Hans-WernerSchockPhotovoltaicmaterials,history,statusandoutlook.MaterialsScienceandEngineeringR40(2003)1–46Efficiencies:4.3%參考文獻(xiàn)虞麗生.半導(dǎo)體異質(zhì)節(jié)物理.北京:科學(xué)出版社,2006,30.姜月順,李鐵津.光化學(xué).北京:化學(xué)工業(yè)出版社,2005,295.DonaldA.Neamen.SemiconductorPhysicsanddevices.2005,75.Arnulf

J?ger-Waldau,PVStatusReport2003,EuropeanCommission,DGJRC,InstituteforEnvironmentandSustainability,RenewableEnergiesUnit,2003,4A