Spatially resolved photoconductivity of thin films formed by colloidal octapod-shaped CdSe/CdS nanocrystals

Yang Zhang; Karol Miszta; Stefan Kudera; Liberato Manna; Enzo Di Fabrizio; Roman Krahne

doi:10.1039/c1nr10251f

Spatially resolved photoconductivity of thin films formed by colloidal octapod-shaped CdSe/CdS nanocrystals

Yang Zhang, Karol Miszta, Stefan Kudera, Liberato Manna, Enzo Di Fabrizio, Roman Krahne^*

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

11 Scopus citations

Abstract

We studied the optical absorption and photoconductive properties of thin films consisting of core-shell octapod-shaped nanocrystals, which consisted of CdS pods that branch out from a CdSe core. The current-voltage characteristics were measured at room and cryogenic temperatures and agreed well with a phenomenological exponential fitting model, from which we could extract the sheet resistance and the average voltage barrier for the charge tunneling between the octapods. The temperature dependence of the photocurrent showed temperature activated behavior above 220 K and a non-Arrhenius exponential (T/T₀)ⁿ dispersion below 220 K. Furthermore, we mapped the photocurrent generation within the octapod film via scanning photocurrent microscopy, which revealed photocurrent enhancement near micron-size voids and spatial shifts of the photocurrent maxima with bias voltage.

Original language	English (US)
Pages (from-to)	2964-2970
Number of pages	7
Journal	Nanoscale
Volume	3
Issue number	7
DOIs	https://doi.org/10.1039/c1nr10251f
State	Published - Jul 2011
Externally published	Yes

ASJC Scopus subject areas

General Materials Science

Access to Document

10.1039/c1nr10251f

Cite this

@article{324b469b6e2b4f8d8cd8ac10e9776156,

title = "Spatially resolved photoconductivity of thin films formed by colloidal octapod-shaped CdSe/CdS nanocrystals",

abstract = "We studied the optical absorption and photoconductive properties of thin films consisting of core-shell octapod-shaped nanocrystals, which consisted of CdS pods that branch out from a CdSe core. The current-voltage characteristics were measured at room and cryogenic temperatures and agreed well with a phenomenological exponential fitting model, from which we could extract the sheet resistance and the average voltage barrier for the charge tunneling between the octapods. The temperature dependence of the photocurrent showed temperature activated behavior above 220 K and a non-Arrhenius exponential (T/T0)n dispersion below 220 K. Furthermore, we mapped the photocurrent generation within the octapod film via scanning photocurrent microscopy, which revealed photocurrent enhancement near micron-size voids and spatial shifts of the photocurrent maxima with bias voltage.",

author = "Yang Zhang and Karol Miszta and Stefan Kudera and Liberato Manna and {Di Fabrizio}, Enzo and Roman Krahne",

year = "2011",

month = jul,

doi = "10.1039/c1nr10251f",

language = "English (US)",

volume = "3",

pages = "2964--2970",

journal = "Nanoscale",

issn = "2040-3364",

publisher = "Royal Society of Chemistry",

number = "7",

}

TY - JOUR

T1 - Spatially resolved photoconductivity of thin films formed by colloidal octapod-shaped CdSe/CdS nanocrystals

AU - Zhang, Yang

AU - Miszta, Karol

AU - Kudera, Stefan

AU - Manna, Liberato

AU - Di Fabrizio, Enzo

AU - Krahne, Roman

PY - 2011/7

Y1 - 2011/7

N2 - We studied the optical absorption and photoconductive properties of thin films consisting of core-shell octapod-shaped nanocrystals, which consisted of CdS pods that branch out from a CdSe core. The current-voltage characteristics were measured at room and cryogenic temperatures and agreed well with a phenomenological exponential fitting model, from which we could extract the sheet resistance and the average voltage barrier for the charge tunneling between the octapods. The temperature dependence of the photocurrent showed temperature activated behavior above 220 K and a non-Arrhenius exponential (T/T0)n dispersion below 220 K. Furthermore, we mapped the photocurrent generation within the octapod film via scanning photocurrent microscopy, which revealed photocurrent enhancement near micron-size voids and spatial shifts of the photocurrent maxima with bias voltage.

AB - We studied the optical absorption and photoconductive properties of thin films consisting of core-shell octapod-shaped nanocrystals, which consisted of CdS pods that branch out from a CdSe core. The current-voltage characteristics were measured at room and cryogenic temperatures and agreed well with a phenomenological exponential fitting model, from which we could extract the sheet resistance and the average voltage barrier for the charge tunneling between the octapods. The temperature dependence of the photocurrent showed temperature activated behavior above 220 K and a non-Arrhenius exponential (T/T0)n dispersion below 220 K. Furthermore, we mapped the photocurrent generation within the octapod film via scanning photocurrent microscopy, which revealed photocurrent enhancement near micron-size voids and spatial shifts of the photocurrent maxima with bias voltage.

UR - http://www.scopus.com/inward/record.url?scp=79960191634&partnerID=8YFLogxK

U2 - 10.1039/c1nr10251f

DO - 10.1039/c1nr10251f

M3 - Article

C2 - 21643586

AN - SCOPUS:79960191634

SN - 2040-3364

VL - 3

SP - 2964

EP - 2970

JO - Nanoscale

JF - Nanoscale

IS - 7

ER -

Spatially resolved photoconductivity of thin films formed by colloidal octapod-shaped CdSe/CdS nanocrystals

Abstract

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this