Nanostructured Absorbers for Multiple Transition Solar Cells
Nanostructured Absorbers for Multiple Transition Solar Cells
复制标题
用于多跃迁太阳能电池的纳米结构吸收体
DOI：
--
复制
发表时间：
2008
影响因子：
3.1
通讯作者：
C. Honsberg
中科院分区：
文献类型：
--
作者：
M. Levy;C. Honsberg
这篇论文确定了用纳米结构异质结实现的多过渡太阳能电池的吸收剂[例如，具有准费米能级变化的量子阱太阳能电池和量子点（QD）中间带太阳能电池]。在辐射极限下，使用这些吸收剂的太阳能电池能够实现转换效率ges50%，几何太阳能集中度至少为1000倍。该技术方法列举了一套定量设计规则，并将这些规则应用于技术上重要的III-V族半导体及其三元合金。一种新的设计规则要求势垒材料和受限材料之间的价带不连续性可以忽略不计。另一个关键的设计规则规定，衬底的晶格常数在势垒材料的晶格常数和量子限制材料的晶格常数之间，这允许应变补偿。应变补偿又允许将大量QD层并入太阳能电池中，因为每一层都没有缺陷。确定了四种候选材料系统（约束/势垒/衬底）：InP 0.85Sb 0.15/GaAs/InP、InAs 0.40P 0.60/GaAs/InP、InAs/GaAs 0.88Sb 0.12/InP和InP/GaAs 0.70P 0.30/GaAs。从设计特点，候选系统也可能会发现在其他光电应用的使用。
This paper identifies absorbers for multiple transition solar cells that are implemented with nanostructured heterojunctions [e.g., quantum well solar cells with quasi-Fermi-level variations and quantum dot (QD) intermediate-band solar cells]. In the radiative limit, the solar cells implemented with these absorbers are capable of achieving a conversion efficiency ges50% with a geometric solar concentration of at least 1000times. The technical approach enumerates a set of quantitative design rules and applies the rules to the technologically important III-V semiconductors and their ternary alloys. A novel design rule mandates a negligible valence band discontinuity between the barrier material and confined materials. Another key design rule stipulates that the substrate have a lattice constant in between that of the barrier material and that of the quantum-confined material, which permits strain compensation. Strain compensation, in turn, allows a large number of QD layers to be incorporated into the solar cell because each layer is free of defects. Four candidate materials systems (confined/barrier/substrate) are identified: InP0.85Sb0.15/GaAs/InP, InAs0.40P0.60/GaAs/InP, InAs/GaAs0.88Sb0.12/InP, and InP/GaAs0.70P0.30/GaAs. Resulting from the design features, the candidate systems may also find use in other optoelectronic applications.