Enhanced Conductivity Boosts the Cathodic Performance of Aluminium-Doped SrTiO₃ in Rechargeable Alkaline Zinc Battery

Abstract

Rechargeable alkaline zinc batteries (RAZBs) have attracted great attention due to their inexpensive use of electrode materials and high safety features. However, the development of RAZBs is restricted by their low capacity and volumetric energy density, mainly suffering from poor electric conductivity of the cathode. Aluminium-doped SrTiO 3 (1.0% Al-STO) has successfully enhanced the capacity of pristine STO from 387 to 646 mAh cm −3 at a current density of 2 mA cm −2 . This may be attributed to the fact that Al doping improves electrical conductivity as well as promoting the transportation of ions/electrons. Based on the Nyquist plot, the charge-transfer resistance of Al-STO was reduced from 7.8 to 1.2 Ω, indicating the enhancement of electrical conductivity after Al doping. This outstanding electrochemical performance of Al-STO as cathode provide valuable insights for designing high-performance electrode for RAZBs.

Effects of Al Doping on Hydrogen Production Efficiency upon Photostimulated Water Splitting on SrTiO3 Nanoparticles

“…The positively shifted peak at 75.4 eV represents the Al 3+ species present near the interface and their negligible amount in our samples confirm that Al is well-doped within the STO lattice as Al 3+ ions. XPS data for Ti 2p states show a doublet at 458.0 and 463.7 eV, corresponding to Ti 4+ species (Figure b) . The spacing of 5.7 eV between these spin–orbit components is consistent with that of Ti oxides.…”

“…XPS data for Ti 2p states show a doublet at 458.0 and 463.7 eV, corresponding to Ti 4+ species (Figure 3b). 49 The spacing of 5.7 eV between these spin−orbit components is consistent with that of Ti oxides. It is worth noting that there were no evident peaks for Ti 3+ species in STO samples, as reported by some researchers for STO.…”

“…The spacing of 5.7 eV between these spin–orbit components is consistent with that of Ti oxides. It is worth noting that there were no evident peaks for Ti 3+ species in STO samples, as reported by some researchers for STO. , The introduction of Al has no apparent effect on the Ti 2p states but it modifies the O 1s states of STO, as seen in Figure c. The first O 1s peak at binding energy (BE) of 529.1–529.2 eV signifies oxygen within the STO lattice (O lat ), while the higher energy peaks correspond to oxygen atoms in the vicinity of an oxygen vacancy (O vac ). , When compared to the peak area of STO, the peak area of O vac increases from 23 to 33% for Al-STO, suggesting an increase in the oxygen vacancies with the incorporation of Al .…”

“…It is worth noting that there were no evident peaks for Ti 3+ species in STO samples, as reported by some researchers for STO. 49,50 The introduction of Al has no apparent effect on the Ti 2p states but it modifies the O 1s states of STO, as seen in Figure 3c. The first O 1s peak at binding energy (BE) of 529.1−529.2 eV signifies oxygen within the STO lattice (O lat ), while the higher energy peaks correspond to oxygen atoms in the vicinity of an oxygen vacancy (O vac ).…”