常见半导体能级图.ppt

.常用的半导体材料SCEg(eV)lbg(nm)SCEg(eV)lbg(nm)SnO23.5350CdS2.4520ZnO3.2390CdSe1.7730SrTiO33.2390CdTe1.4890TiO23.0410GaAs1.4890Fe2O32.1520InP1.3950GaP2.3540Si1.11130.太阳的幅射能Air mass幅射功率光子流平均能量AMW/cm2Ne/sm2eVAM013505.8x10211.48AM110605.0 x10211.32AM28804.3x10211.28AM37503.9x10211.21.半导体光分解反应热力学稳定性能级图CBVBnEDCBVBCBVBnEDnEDnEDpEDpEDCBVBpEDpED稳定，阴极稳定，阳极稳定，不稳定从反应相应的自由能变化进行热力学计算，可得到半导体的阴极和阳极分解反应的标准平衡电势+-.QuantumDotsMetalsCeramicsCarbonsOrganicOpticalMagneticMechanicalElectricalCatalyticSorptive纳米材料及特性.临界尺寸(in nm)低限低限高限高限临界尺寸及现象临界尺寸及现象半导体量子半导体量子点点 15 nm for CdSe,emission金属金属 100 nm for Au,scattering陶瓷陶瓷 40 nm for magnetic(Hc)碳碳-all different,structure-有机物有机物Size dependence only S/VGenerally true for isolated nanoparticles produced in bottoms-up methods1 nm1 nm2 nm.7 nm1 nm15 nm100 nm50 nm2 nm100 nm.Reduced DimensionalityBased on Bimberg(1999)BulkQuantum WellQuantum WireQuantum DotEnergyr3D(E)Energyr2D(E)e1e3e2e4Energyr1D(E)e1,1e1,2e1,3Energyr0D(E)Confining the electron motion in at least one spatial dimension affects the energy levels and the density of states.半导体纳晶多孔薄膜纳米尺寸的半导体超微粒子烧结而构成的粒子相互连接所形成的三维网络多孔结构单粒子的能级量子化微结构的影响无空间电荷层本征导导率电子输运光散射特性e.