10.1021/jp300085n.s001
Gosuke Oyama
Gosuke
Oyama
Yuki Yamada
Yuki
Yamada
Ryu-ichi Natsui
Ryu-ichi
Natsui
Shin-ichi Nishimura
Shin-ichi
Nishimura
Atsuo Yamada
Atsuo
Yamada
Kinetics of Nucleation and Growth in Two-Phase Electrochemical
Reaction of Li<sub><i>x</i></sub>FePO<sub>4</sub>
American Chemical Society
2012
KJMA
phase transition proceeds
electrode
movement
LixFePO 4The kinetics
LixFePO 4
chronoamperogram
2012-04-05 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Kinetics_of_Nucleation_and_Growth_in_Two_Phase_Electrochemical_Reaction_of_Li_sub_i_x_i_sub_FePO_sub_4_sub_/2534584
The kinetics of a two-phase electrochemical reaction in Li<sub><i>x</i></sub>FePO<sub>4</sub> was investigated by potential-step
chronoamperometry under various experimental conditions: amplitude
of potential step, direction of potential step, particle size, and
thickness of composite electrodes. Only under a small potential step
(10 mV) applied to large Li<sub><i>x</i></sub>FePO<sub>4</sub> particles (203 nm), the chronoamperogram showed a momentary current
increase, followed by gradual decline, indicating that the nucleation
and growth governed the electrode kinetics. In that condition, the
chronoamperogram was analyzed with the Kolmogorov–Johnson–Mehl–Avrami
(KJMA) model, which describes the kinetics of phase transition. The
obtained Avrami exponent of ca. 1.1 indicates that the phase transition
proceeds with a one-dimensional phase-boundary movement, which is
consistent with the previously reported mechanism. From the temperature
dependence of the obtained rate constant, the activation energy of
the phase-boundary movement in Li<sub><i>x</i></sub>FePO<sub>4</sub> was estimated to be 42 and 40 kJ mol<sup>–1</sup> in
cathodic and anodic reactions, respectively.