TY - JOUR
T1 - Mapping Shunting Paths at the Surface of Cu2ZnSn(S,Se)(4) Films via Energy-Filtered Photoemission Microscopy
AU - Tiwari, Devendra
AU - Cattelan, Mattia
AU - Harniman, Robert L.
AU - Sarua, Andrei
AU - Abbas, Ali
AU - Bowers, Jake W.
AU - Fox, Neil A.
AU - Fermin, David J.
PY - 2018/11/30
Y1 - 2018/11/30
N2 - The performance of Cu2ZnSn(S,Se)4 thin-film solar cells, commonly referred to as kesterite or CZTSSe, is limited by open-circuit voltage (VOC) values less than 60% of the maximum theoretical limit. In the present study, we employ energy-filtered photoemission microscopy to visualize nanoscale shunting paths in solution-processed CZTSSe films, which limit the VOC of cells to approximately 400 mV. These studies unveil areas of local effective work function (LEWF) narrowly distributed around 4.9 eV, whereas other portions show hotspots with LEWF as low as 4.2 eV. Localized valence band spectra and density functional theory calculations allow rationalizing the LEWF maps in terms of the CZTSSe effective work function broadened by potential energy fluctuations and nanoscale Sn(S,Se) phases.
AB - The performance of Cu2ZnSn(S,Se)4 thin-film solar cells, commonly referred to as kesterite or CZTSSe, is limited by open-circuit voltage (VOC) values less than 60% of the maximum theoretical limit. In the present study, we employ energy-filtered photoemission microscopy to visualize nanoscale shunting paths in solution-processed CZTSSe films, which limit the VOC of cells to approximately 400 mV. These studies unveil areas of local effective work function (LEWF) narrowly distributed around 4.9 eV, whereas other portions show hotspots with LEWF as low as 4.2 eV. Localized valence band spectra and density functional theory calculations allow rationalizing the LEWF maps in terms of the CZTSSe effective work function broadened by potential energy fluctuations and nanoscale Sn(S,Se) phases.
UR - https://www.scopus.com/pages/publications/85061459950
U2 - 10.1016/j.isci.2018.10.004
DO - 10.1016/j.isci.2018.10.004
M3 - Article
SN - 2589-0042
VL - 9
SP - 36
EP - 46
JO - iScience
JF - iScience
ER -
