Facile synthesis of α-MoO3 nanobelts and their pseudocapacitive behavior in an aqueous Li2SO4 solution

Abstract

a-MoO 3 nanobelts were successfully prepared by a facile hydrothermal method with sodium molybdate (Na 2 MoO 4 ) as the Mo source and NaCl as the capping agent. The as-prepared products were characterized using Fourier transformation infrared spectrophotometry (FT-IR), X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and selected area electronic diffraction (SAED) and their pseudocapacitive properties were investigated in a 0.5 M aqueous Li 2 SO 4 solution by cyclic voltammetry (CV), chronopotentiometry (CP) and AC impendence. The results show that the dimensions of the as-prepared a-MoO 3 nanobelts are 200-400 nm in width, ca. 60 nm in thickness and 3-8 mm in length. The redox potential for the a-MoO 3 nanobelts is found in the range of À0.3 to À1.0 V vs. SCE, which indicates that the a-MoO 3 nanobelts can be used as anode electrode materials for hybrid supercapacitors. The specific capacitances of the a-MoO 3 nanobelts at 0.1, 0.25, 0.5 and 1 A g À1 are 369, 326, 256 and 207 F g À1 , respectively. The maximum specific capacitance of the a-MoO 3 nanobelts is much higher than those of MoO 3 nanoplates with 280 F g À1 , MoO 3 nanowires with 110 F g À1 and MoO 3 nanorods with 30 F g À1 recently reported in literature. Furthermore, the a-MoO 3 nanobelt electrode exhibits a good cycle stability with more than 95% of the initial specific capacitance maintained after 500 cycles. Additionally, the present route to prepare nanostructured MoO 3 is much less expensive than those with Mo powders as the Mo source. Overall, the obtained high performance a-MoO 3 nanobelts could be a promising electrode material for supercapacitors.

Aqueous Crystallization Strategy for Metastable h‐MoO3 Crystals with Polyvinylpyrrolidone Induction

“…In recent years, much work has been devoted to the preparation of metal oxide micro‐ and nanostructures, especially those of transition metal oxides, owing to their potential applications in science and technology 1–5. Among these materials, molybdenum trioxide (MoO 3 ) has attracted considerable interest6–10 because of its distinctive properties in supported catalysts, chemical sensors, batteries, displays, imaging devices, smart windows, and solar energy conversion 11–19…”

Synthesis and characterization of α-MoO3 nanobelt composite positive electrode materials for lithium battery application

“…The SEM images of pure MoO 3 nanobelts and 6.25 wt%, 12.5 wt% PEO surfactant 040) and (060) diffraction peaks of the pure MoO 3 nanobelts are stronger than those of other peaks, which is different from the standard spectrum of the reported α-MoO 3 [36,37] implying that there is a layered crystal structure or a highly anisotropic growth for the prepared nanobelts [38][39][40]. The peak intensity of 12.5 wt% PEO surfactant MoO 3 nanobelts is obviously weaker than the pure MoO 3 nanobelts.…”

Formation of hexagonal-molybdenum trioxide (h-MoO3) nanostructures and their pseudocapacitive behavior

“…More recently, the highest achievable specific capacitance of 326 F g −1 (at 0.25 A g −1 ) using α-MoO 3 nanobelts has been reported, but the loading mass tends to be low (∼0.51 mg). 28 Also, the specific capacitance of α-MoO 3 nanoplates as high as 280 F g −1 (calculated from non-rectangular CV curves) has been achieved, benefiting from the small diffusion length of the ions into the nanosheets. 29 Most recently, Chang et al introduced the concept of the work function difference to enhance the working potential window of an asymmetric supercapacitor device based on rGO-α-MoO 3 , in an aqueous electrolyte solution.…”