Premium
Toward Cost‐Effective Manufacturing of Silicon Solar Cells: Electrodeposition of High‐Quality Si Films in a CaCl 2 ‐based Molten Salt
Author(s) -
Yang Xiao,
Ji Li,
Zou Xingli,
Lim Taeho,
Zhao Ji,
Yu Edward T.,
Bard Allen J.
Publication year - 2017
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201707635
Subject(s) - materials science , impurity , silicon , photocurrent , molten salt , graphite , chemical engineering , substrate (aquarium) , salt (chemistry) , solar cell , semiconductor , electrolyte , metallurgy , optoelectronics , electrode , chemistry , organic chemistry , oceanography , engineering , geology
Electrodeposition of Si films from a Si‐containing electrolyte is a cost‐effective approach for the manufacturing of solar cells. Proposals relying on fluoride‐based molten salts have suffered from low product quality due to difficulties in impurity control. Here we demonstrate the successful electrodeposition of high‐quality Si films from a CaCl 2 ‐based molten salt. Soluble Si IV −O anions generated from solid SiO 2 are electrodeposited onto a graphite substrate to form a dense film of crystalline Si. Impurities in the deposited Si film are controlled at low concentrations (both B and P are less than 1 ppm). In the photoelectrochemical measurements, the film shows p‐type semiconductor character and large photocurrent. A p–n junction fabricated from the deposited Si film exhibits clear photovoltaic effects. This study represents the first step to the ultimate goal of developing a cost‐effective manufacturing process for Si solar cells based on electrodeposition.