Direct Growth of Bismuth Film as Anode for Aqueous Rechargeable Batteries in LiOH, NaOH and KOH Electrolytes.

Wenhua Zuo,Yuanyuan Li,Pan Xu,Jinping Liu

doi:10.3390/nano5041756

Abstract

As promising candidates for next-generation energy storage devices, aqueous rechargeable batteries are safer and cheaper than organic Li ion batteries. But due to the narrow voltage window of aqueous electrolytes, proper anode materials with low redox potential and high capacity are quite rare. In this work, bismuth electrode film was directly grown by a facile hydrothermal route and tested in LiOH, NaOH and KOH electrolytes. With low redox potential (reduction/oxidation potentials at ca. −0.85/−0.52 V vs. SCE, respectively) and high specific capacity (170 mAh·g−1 at current density of 0.5 A·g−1 in KOH electrolyte), Bi was demonstrated as a suitable anode material for aqueous batteries. Furthermore, by electrochemical impedance spectroscopy (EIS) analysis, we found that with smaller Rs and faster ion diffusion coefficient, Bi electrode film in KOH electrolyte exhibited better electrochemical performance than in LiOH and NaOH electrolytes.

Highlights

Because of their distinctive electrochemical performance compared to other energy storage systems, lithium ion batteries (LIBs) with organic electrolyte have been the most successful energy storage device for portable electronics in the last decades and considered as the prime choice to supply power for future electric vehicles, etc. [1]
The alloying anode materials for LIB and NIB such as Si, Sb, Sn and their compounds have very high specific capacity, but due to the very low redox potential, they are unqualified for the anode of aqueous rechargeable alkali-metal ion batteries (ARABs)
The energy storage property of Bi electrode in LiOH, NaOH and KOH aqueous solutions is firstly investigated, and we demonstrate that Bi is a promising anode for ARABs with high capacity of 170 mAh g−1 and relatively low redox potential range (−1~0 V)

Summary

Introduction

Because of their distinctive electrochemical performance compared to other energy storage systems, lithium ion batteries (LIBs) with organic electrolyte have been the most successful energy storage device for portable electronics in the last decades and considered as the prime choice to supply power for future electric vehicles, etc. [1]. Besides achieving the critical electrochemical performance of specific capacity, cycling and rate capability, the electrode materials for ARABs have to work in a narrow and appropriate potential range to gain a relatively high battery voltage. Proposed a “carbon shell-protection” solution and fabricated binder-free Fe3O4-C nanorod array anode achieving high capacity (7776 C·cm−3), stable cycling performance (>5000 times) and excellent rate capability within a working potential window of −1.3~−0.5 V (vs Ag/AgCl) [30]. With such morphology modification, Fe3O4 become a very impressive anode material for aqueous battery. The energy storage property of Bi electrode in LiOH, NaOH and KOH aqueous solutions is firstly investigated, and we demonstrate that Bi is a promising anode for ARABs with high capacity of 170 mAh g−1 and relatively low redox potential range (−1~0 V)

Results and Discussion

A2 n 4 F 4C 4σ 2

Sample Preparation and Characterization

Electrochemical Characterization

Conclusions