TY - JOUR
T1 - Lithiation of pure and methylated amorphous silicon
T2 - Monitoring by operando optical microscopy and ex situ atomic force microscopy
AU - Feng, Yue
AU - Ngo, Thuy Doan Trang
AU - Panagopoulou, Marianthi
AU - Cheriet, Abdelhak
AU - Koo, Bon Min
AU - Henry-de-Villeneuve, Catherine
AU - Rosso, Michel
AU - Ozanam, François
N1 - Publisher Copyright:
© 2019 Elsevier Ltd
PY - 2019/4/10
Y1 - 2019/4/10
N2 - Operando color microscopy and ex situ AFM were used to investigate the lithiation process in pure (a-Si:H) and methylated (a-Si 1-x (CH 3 ) x :H) amorphous silicon thin layers. Color analysis of optical images allows for monitoring thickness changes of a-Si:H layers. Unlike pure a-Si:H, the first lithiation of a-Si 1-x (CH 3 ) x :H is found to be spatially non-uniform: lithiation starts at a limited number of locations then expands radially, forming circular lithiation spots. The morphology of the lithiation spots and their evolution is accurately measured by ex situ AFM. A mechanism is proposed to explain this phenomenon, involving the high resistivity of methylated silicon and the existence of low-resistance point defects.
AB - Operando color microscopy and ex situ AFM were used to investigate the lithiation process in pure (a-Si:H) and methylated (a-Si 1-x (CH 3 ) x :H) amorphous silicon thin layers. Color analysis of optical images allows for monitoring thickness changes of a-Si:H layers. Unlike pure a-Si:H, the first lithiation of a-Si 1-x (CH 3 ) x :H is found to be spatially non-uniform: lithiation starts at a limited number of locations then expands radially, forming circular lithiation spots. The morphology of the lithiation spots and their evolution is accurately measured by ex situ AFM. A mechanism is proposed to explain this phenomenon, involving the high resistivity of methylated silicon and the existence of low-resistance point defects.
KW - AFM
KW - Amorphous silicon
KW - Li-ion battery
KW - Lithiation mechanism
KW - Operando optical microscopy
KW - Silicon anode
UR - http://www.scopus.com/inward/record.url?scp=85062150001&partnerID=8YFLogxK
U2 - 10.1016/j.electacta.2019.02.016
DO - 10.1016/j.electacta.2019.02.016
M3 - Article
AN - SCOPUS:85062150001
SN - 0013-4686
VL - 302
SP - 249
EP - 258
JO - Electrochimica Acta
JF - Electrochimica Acta
ER -