@article {Chen2018,
	title = {Above 10\% Efficiency Earth-abundant Cu2ZnSn(S,Se)4 Solar Cells by Introducing Alkali Metal Fluoride Nanolayers as Electron-selective Contacts},
	journal = {Nano Energy},
	year = {2018},
	note = {n/a},
	pages = {-},
	abstract = {<p>Abstract The present investigation mainly addresses the open circuit voltage (Voc) issue in kesterites based Cu2ZnSn(S,Se)4 solar cells by simply introducing alkali metal fluoride nanolayers (~ several nm NaF, or LiF) to lower the work functions of the front {\.I}TO\} contacts without conventional hole-blocking ZnO layers. Kelvin probe measurements confirmed that the work function of the front {\.I}TO\} decreases from 4.82 to 3.39 and 3.65 eV for NaF and LiF, respectively, resulting in beneficial band alignment for electron collection and/or hole blocking on top electrodes. Moreover, a 10.4\% power conversion efficiency (~11.5\% in the cell effective area) \{CZTSSe\} cell with improved Voc of up to 90 mV has been attained. This demonstration may provide a new direction of further boosting the performance of copper chalcogenide based solar cells as well.</p>
},
	keywords = {Solar cells},
	issn = {2211-2855},
	doi = {https://doi.org/10.1016/j.nanoen.2018.06.028},
	url = {https://www.sciencedirect.com/science/article/pii/S2211285518304233},
	author = {Cheng-YingChen and Bandiyah Sri Aprillia and Wei-ChaoChen and Yen-Ching Teng and Chih-Yuan Chiu and Ruei-San Chen and Jih-Shang Hwang and Kuei-Hsien Chen and Li-Chyong Chen}
}
