Cooling and Auger Recombination of Charges in PbSe Nanorods: Crossover from Cubic to Bimolecular Decay

被引：26

作者：

Aerts, Michiel ^{[1
]}

Spoor, Frank C. M. ^{[1
]}

Grozema, Ferdinand C. ^{[1
]}

Houtepen, Arjan J. ^{[1
]}

Schins, Juleon M. ^{[1
]}

Siebbeles, Laurens D. A. ^{[1
]}

机构：

[1] Delft Univ Technol, Optoelect Mat Sect, Dept Chem Engn, NL-2628 BL Delft, Netherlands

来源：

NANO LETTERS | 2013年 / 13卷 / 09期

关键词：

PbSe; nanorods; quantum dots; Auger recombination; charge cooling; MULTIPLE EXCITON GENERATION; SEMICONDUCTOR QUANTUM DOTS; CARRIER MULTIPLICATION; ELECTRONIC-STRUCTURE; CDSE NANOCRYSTALS; SOLAR-CELL; EFFICIENCY; RELAXATION; PROSPECTS; CUBES;

D O I：

10.1021/nl402223q

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The cooling and Auger recombination of electron hole pairs in PbSe quantum dots (QDs) and a series of nanorods (NRs) with similar diameter and varying length was studied by ultrafast pump-probe laser spectroscopy. Hot exciton cooling rates are found to be independent of nanocrystal shape. The energy relaxation rate decreases during cooling of charges, due to reduction of the density of electronic states. Auger recombination occurs via cubic third-order kinetics of uncorrelated charges in the QDs and Nits with length up to 29 nm. On increasing the NR length to 52 nm, a crossover to bimolecular exciton decay is found, This suggests a spatial extent of the one-dimensional exciton of 30-50 nm, which is significantly smaller than the value of 92 nm for the three-dimensional exciton diameter in bulk PbSe. The Auger decay time increases with NR length, which is beneficial for applications in nanocrystal lasers as well as for generation of free charges in photovoltaics.

引用

页码：4380 / 4386

页数：7

共 34 条

[1] The peculiar electronic structure of PbSe quantum dots [J].

An, J. M. ;

Franceschetti, A. ;

Dudiy, S. V. ;

Zunger, Alex .

NANO LETTERS, 2006, 6 (12) :2728-2735

[2] Electronic states and optical properties of PbSe nanorods and nanowires [J].

Bartnik, A. C. ;

Efros, Al. L. ;

Koh, W. -K. ;

Murray, C. B. ;

Wise, F. W. .

PHYSICAL REVIEW B, 2010, 82 (19)

[3] Stochastic models of charge carrier dynamics in semiconducting nanosystems [J].

Barzykin, A. V. ;

Tachiya, M. .

JOURNAL OF PHYSICS-CONDENSED MATTER, 2007, 19 (06)

[4] Multiple Exciton Generation in Semiconductor Quantum Dots [J].

Beard, Matthew C. .

JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 2011, 2 (11) :1282-1288

[5]

BEARD MC, 2013, J ACC CHEM RES, V46, P1252, DOI DOI 10.1021/AR3001958

[6] Flat Colloidal Semiconductor Nanoplatelets [J].

Bouet, Cecile ;

Tessier, Mickael D. ;

Ithurria, Sandrine ;

Mahler, Benoit ;

Nadal, Brice ;

Dubertret, Benoit .

CHEMISTRY OF MATERIALS, 2013, 25 (08) :1262-1271

[7] Strong configuration mixing due to dielectric confinement in semiconductor nanorods [J].

Climente, J. I. ;

Royo, M. ;

Movilla, J. L. ;

Planelles, J. .

PHYSICAL REVIEW B, 2009, 79 (16)

[8] Enhanced Multiple Exciton Generation in Quasi-One-Dimensional Semiconductors (vol 11, pg 3476, 2011) [J].

Cunningham, Paul D. ;

Boercker, Janice E. ;

Foos, Edward E. ;

Lumb, Matthew P. ;

Smith, Anthony R. ;

Tischler, Joseph G. ;

Melinger, Joseph S. .

NANO LETTERS, 2013, 13 (06) :3003-3003

[9] Enhanced Multiple Exciton Generation in Quasi-One-Dimensional Semiconductors [J].

Cunningham, Paul D. ;

Boercker, Janice E. ;

Foos, Edward E. ;

Lumb, Matthew P. ;

Smith, Anthony R. ;

Tischler, Joseph G. ;

Melinger, Joseph S. .

NANO LETTERS, 2011, 11 (08) :3476-3481

[10]

Haug H., 2001, QUANTUM THEORY OPTIC, Vthird

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