TY - JOUR
T1 - Trap-Induced Dispersive Transport and Dielectric Loss in PbS Nanoparticle Films
AU - Chanaewa, Alina
AU - Poulsen, Katharina
AU - Gräfe, Alexander
AU - Gimmler, Christoph
AU - Von Hauff, Elizabeth
PY - 2017
Y1 - 2017
N2 - In this work, we investigate the electrical and dielectric response of lead sulfide (PbS) nanoparticle (NP) films with impedance spectroscopy. In particular, the influence of the ligand passivation on the surface trap state density of PbS NPs is demonstrated by comparing two different types of ligands: ethane-1,2-dithiol (EDT) and 3-sulfanylpropanoic acid (MPA). We observe that the MPA treatment passivates the PbS surface more efficiently than EDT. By analyzing the dielectric loss spectra, we are able to visualize shallow trap states in the bulk of PbS-EDT films and correlate this with the dispersive response observed in the impedance spectra. Evidence of deep trap states is revealed for both PbS-EDT and PbS-MPA diodes. Under illumination, the PbS-MPA and PbS-EDT films demonstrate almost identical trap profiles, showing solely the deep trap state densities. We conclude that the deep traps are related to the stoichiometry of the PbS NPs.
AB - In this work, we investigate the electrical and dielectric response of lead sulfide (PbS) nanoparticle (NP) films with impedance spectroscopy. In particular, the influence of the ligand passivation on the surface trap state density of PbS NPs is demonstrated by comparing two different types of ligands: ethane-1,2-dithiol (EDT) and 3-sulfanylpropanoic acid (MPA). We observe that the MPA treatment passivates the PbS surface more efficiently than EDT. By analyzing the dielectric loss spectra, we are able to visualize shallow trap states in the bulk of PbS-EDT films and correlate this with the dispersive response observed in the impedance spectra. Evidence of deep trap states is revealed for both PbS-EDT and PbS-MPA diodes. Under illumination, the PbS-MPA and PbS-EDT films demonstrate almost identical trap profiles, showing solely the deep trap state densities. We conclude that the deep traps are related to the stoichiometry of the PbS NPs.
KW - dielectric analysis
KW - impedance spectroscopy
KW - PbS nanoparticle films
KW - transport
KW - trap states
UR - http://www.scopus.com/inward/record.url?scp=85008958239&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85008958239&partnerID=8YFLogxK
U2 - 10.1515/zpch-2016-0906
DO - 10.1515/zpch-2016-0906
M3 - Article
AN - SCOPUS:85008958239
SN - 0942-9352
VL - 231
SP - 121
EP - 134
JO - ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS
JF - ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS
IS - 1
ER -