title: Built-in potential and charge distribution within single heterostructured nanorods measured by scanning Kelvin probe microscopy.
abstract: The electrostatic potential distribution across single, isolated, colloidal heterostructured nanorods (NRs) with component materials expected to form a p-n junction within each NR has been measured using scanning Kelvin probe microscopy (SKPM). We compare CdS to bicomponent CdS-CdSe, CdS-PbSe, and CdS-PbS NRs prepared via different synthetic approaches to corroborate the SKPM assignments. The CdS-PbS NRs show a sharp contrast in measured potential across the material interface. We find the measured built-in potential within an individual NR to be attenuated by long-range electrostatic forces between the sample substrate, cantilever, and the measuring tip. Surface potential images were deconvoluted to yield built-in potentials ranging from 375 to 510 meV in the heterostructured NRs. We deduce the overall built-in potential as well as the charge distribution across each segment of the heterostructured NRs by combining SKPM data with simulations of the system.
authors: National Renewable Energy Laboratory, 1617 Cole Blvd., Golden, Colorado, United States.
authors: Sanjini U
authors: SU
authors: Nanayakkara
authors: Gilad
authors: G
authors: Cohen
authors: Chun-Sheng
authors: CS
authors: Jiang
authors: Manuel J
authors: MJ
authors: Romero
authors: Klara
authors: K
authors: Maturova
authors: Mowafak
authors: M
authors: Al-Jassim
authors: Jao
authors: J
authors: van de Lagemaat
authors: Yossi
authors: Y
authors: Rosenwaks
authors: Joseph M
authors: JM
authors: Luther