Quantum funneling in blended multi-band gap core/shell colloidal quantum dot solar cells

被引：8

作者：

Neo, Darren C. J. ^{[1
]}

Stranks, Samuel D. ^{[2
]}

Eperon, Giles E. ^{[2
]}

Snaith, Henry J. ^{[2
]}

Assender, Hazel E. ^{[1
]}

Watt, Andrew A. R. ^{[1
]}

机构：

[1] Univ Oxford, Dept Mat, Oxford OX1 3PH, England

[2] Dept Phys, Clarendon Lab, Oxford OX1 3PU, England

来源：

APPLIED PHYSICS LETTERS | 2015年 / 107卷 / 10期

基金：

英国工程与自然科学研究理事会;

关键词：

PHOTOVOLTAICS; PBS; RECOMBINATION; NANOCRYSTALS; PASSIVATION; GENERATION; TRANSPORT; ABSORBER; SOLIDS; LAYER;

D O I：

10.1063/1.4930144

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Multi-band gap heterojunction solar cells fabricated from a blend of 1.2 eV and 1.4 eV PbS colloidal quantum dots (CQDs) show poor device performance due to non-radiative recombination. To overcome this, a CdS shell is epitaxially formed around the PbS core using cation exchange. From steady state and transient photoluminescence measurements, we understand the nature of charge transfer between these quantum dots. Photoluminescence decay lifetimes are much longer in the PbS/CdS core/shell blend compared to PbS only, explained by a reduction in non-radiative recombination resulting from CdS surface passivation. PbS/CdS heterojunction devices sustain a higher open-circuit voltage and lower reverse saturation current as compared to PbS-only devices, implying lower recombination rates. Further device performance enhancement is attained by modifying the composition profile of the CQD species in the absorbing layer resulting in a three dimensional quantum cascade structure. (C) 2015 AIP Publishing LLC.

引用

页数：5

共 36 条

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