Molybdenum-Suboxide Thin Films as Anode Layers in Planar Lithium Microbatteries

Abstract

In this paper, we investigate the effects of operational conditions on structural, electronic and electrochemical properties on molybdenum suboxides (MoO3-δ) thin films. The films are prepared using pulsed-laser deposition by varying the deposition temperature (Ts), laser fluence (Φ), the partial oxygen pressure (PO2) and annealing temperature (Ta). We find that three classes of samples are obtained with different degrees of stoichiometric deviation without post-treatment: (i) amorphous MoO3-δ (δ < 0.05) (ii) nearly-stoichiometric samples (δ ≈ 0) and (iii) suboxides MoO3-δ (δ > 0.05). The suboxide films 0.05 ≤ δ ≤ 0.25 deposited on Au/Ti/SiO2/flexible-Si substrates with appropriate processing conditions show high electrochemical performance as an anode layer for lithium planar microbatteries. In the realm of simple synthesis, the MoO3-δ film deposited at 450 °C under oxygen pressure of 13 Pa is a mixture of α-MoO3 and Mo8O23 phases (15:85). The electrochemical test of the 0.15MoO3-0.85Mo8O23 film shows a specific capacity of 484 µAh cm−2 µm−1 after 100 cycles of charge-discharge at a constant current of 0.5 A cm−2 in the potential range 3.0-0.05 V.

Growth, characterization and performance of bulk and nanoengineered molybdenum oxides for electrochemical energy storage and conversion

“…1a). The octahedral It is a shallow donor and has a small formation energy in the O poor limit so that MoO3 easily becomes a degenerate semiconductor [71,72]. Figure 1d displays the XRD pattern of the layered α-MoO3 showing fingerprints at 2θ = 12.7°, 23.3°, 25.6°, 27.2°, and 38.9°, which correspond to the (020), ( 110), ( 040), (0.21) and (060) planes (JCPDS card no.…”

“…Magnetic susceptibility measurements showed that MoO3, MoO2 and MonO3n-1 shear suboxides in between are all feebly paramagnetic. Copyright Lakshmi-Narayana et al [72]. Open access article under the CC BY-NC-ND license.…”

“…Recently, the effects of operational conditions on structural, electronic and electrochemical properties on molybdenum suboxides (MoO3-δ) thin films were investigated [72].…”

“…reviewed the progress toward solid-state 3D thin-film Liion microbatteries and discussed the status of the individual components: thin-film cathodes, anodes, and thin-film solid electrolyte. Julien et al investigated the electrochemical performance of molybdenum-suboxide thin films as anode layers in planar lithium microbatteries[72]. Puppala et al investigated the microstructure and morphology of PLD MoO3−x thin films' growth for catalytic applications using a femtosecond laser (f-PLD) and a nanosecond excimer-laser (n-PLD).…”

Fast Growth of Multi-Phase MoOx Synthesized by Laser Direct Writing Using Femtosecond Pulses

“…The commonly known crystalline phases for stochiometric molybdenum oxides are m-MoO 2 , α-MoO 3 , β-MoO 3 , MoO 3 , and h-MoO [36,[43][44][45]. This rich selection of molybdenum oxides has shown potential industrial applications such as sensors, cathodes for lithium ion batteries, photocatalyst, and supercapacitors, among others [45][46][47][48]. It is worth mentioning that both the MoO 2 and MoO 3 crystalline phases have been extensively studied and well characterized by Raman spectroscopy.…”