Tin Oxides as a Negative Electrode Material for Potassium-Ion Batteries

Abstract

As one strategy for increasing energy density of K-ion batteries, electrochemical behavior of Sn oxides (SnO and SnO2) was studied as a negative electrode material. X-ray photoelectron spectroscopy and X-ray diffraction revealed followings: SnO underwent phase separation at the first charge (reduction) process to form metallic Sn and potassium oxide, and reversible alloying reactions between the resulting Sn and K proceeded up to a composition of KSn or more. In contrast, SnO2 showed little electrochemical reactivity to potassium. Interestingly, a reversible capacity obtained from SnO electrode at the initial cycle was comparable to that of Sn alone electrode. SnO electrode exhibited a reversible capacity of 183 mA h g −1 with a 80% capacity retention at the 30th cycle, whereas a capacity of Sn electrode rapidly decreased because of the electrode disintegration induced by the significant volume change during K−Sn alloying/dealloying reactions. No crack and peeling off of an active material layer were confirmed in SnO electrode. Scanning transmission electron microscope image of the SnO electrode after the first cycle displayed that Sn nanoparticles were dispersed in amorphous-like K2O matrices. The reason for the improved cycle stability of SnO electrode is probably that K2O suppressed Sn aggregation and/or play a role as a buffer to volumetric change in Sn. For achieving a further long cycle life of SnO electrode, the optimization of particle size and electrolyte solution, and elemental substitution of part of oxygen would be effective.

Snapshot on Negative Electrode Materials for Potassium-Ion Batteries

“…A few conversion materials were also reported as possible negative electrode for KIB such as Co 3 O 4 -Fe 2 O 3 , tin oxides or antimony and tin sulfides (Lakshmi et al, 2017;Sultana et al, 2017b;Shimizu et al, 2018). Shimizu et al reported the electrochemical activity of SnO, which is irreversibly converted into tin nanoparticles embedded in a stable matrix of K 2 O.…”

“…Shimizu et al reported the electrochemical activity of SnO, which is irreversibly converted into tin nanoparticles embedded in a stable matrix of K 2 O. This matrix hinders the aggregation of the tin nanoparticles, which then undergo alloying reaction with K (Shimizu et al, 2018). Interestingly, SnO exhibits a discharge capacity around 200 mAh/g during 30 cycles, whereas SnO 2 appears to be inactive.…”

Nature of Bimetallic Oxide Sb2MoO6/rGO Anode for High‐Performance Potassium‐Ion Batteries

“…Besides the carbonaceous anodes (graphite, soft carbon, hard carbon, etc.) which are being explored vigorously but yield a relatively low specific capacity, metal oxides, such as iron oxides, molybdenum oxides, niobium pentoxides, tin oxides, and titanium oxides, are interesting anode candidates considering their high gravimetric and volumetric specific capacity, which are able to provide high performance anodes for KIBs . For example, antimony oxide (Sb 2 O 3 ) possesses a theoretical capacity as high as 1103 mAh g −1 for KIBs through both conversion reactions and alloy reactions.…”

“…[1][2][3][4][5] Because of the natural abundance of potassium, a similar redox potential of potassium to lithium, and the low cost, potassiumion batteries (KIBs) serve as a promising substitution to LIBs, [6][7][8][9][10][11] especially attractive in the largescale energy storage systems which strive intensively to lower the price to be competitive with other energy storage techniques. which are being explored vigorously but yield a relatively low specific capacity, [17][18][19][20][21][22][23][24][25][26][27] metal oxides, such as iron oxides, [28] molybdenum oxides, [29,30] niobium pentoxides, [31] tin oxides, [32] and titanium oxides, [33] are interesting anode candidates considering their high gravimetric and volumetric specific capacity, which are able to provide high performance anodes for KIBs. [12][13][14][15][16] Therefore, searching for the high performance KIBs anode (a critical component of KIBs) to alleviate the dramatic volume change is highly demanded to build high performance KIBs.…”

“…which are being explored vigorously but yield a relatively low specific capacity, [17][18][19][20][21][22][23][24][25][26][27] metal oxides, such as iron oxides, [28] molybdenum oxides, [29,30] niobium pentoxides, [31] tin oxides, [32] and titanium oxides, [33] are interesting anode candidates considering their high gravimetric and volumetric specific capacity, which are able to provide high performance anodes for KIBs. which are being explored vigorously but yield a relatively low specific capacity, [17][18][19][20][21][22][23][24][25][26][27] metal oxides, such as iron oxides, [28] molybdenum oxides, [29,30] niobium pentoxides, [31] tin oxides, [32] and titanium oxides, [33] are interesting anode candidates considering their high gravimetric and volumetric specific capacity, which are able to provide high performance anodes for KIBs.…”