Effects of O2 gases addition on enhanced lithium ion intercalation and conduction of flexible-transparent-lithiated tantalum oxide thin films synthesized by an atmospheric pressure plasma jet

• Rapid deposition of Li+ ion conductor LixTaOyCz film using atmospheric pressure plasma jet
• Enhanced Li+ ion intercalation performance of LixTaOyCz films by addition oxygen gases into plasma jet
• Improved Li+ ion conduction performance of LixTaOyCz films by addition oxygen gases into plasma jet
• Nanoporous surfaces of LixTaOyCz films offer fast Li+ ion intercalation and deintercalation

Flexible-transparent-lithiated-lithium tantalum oxide (LixTaOyCz) films deposited onto 40 Ω/□ flexible polyethylene terephthalate/indium tin oxide substrates by low temperature plasma polymerization with an atmospheric pressure plasma jet (APPJ) at various flow rates oxygen gases are investigated. Precursors [lithium tert-butoxide, (CH3)3COLi] and [tantalum ethoxide, Ta(OC2H5)5]2] vapors are carried by argon gas, mixed by oxygen gas and injected into air plasma torch for fast synthesis of LixTaOyCz films by short durations of the substrates, 33–37 s, exposed in the plasmas. The flexible-transparent LixTaOyCz films possess the notable Li+ ion intercalation and conduction performance for 200 cycles of reversible Li+ ion intercalation and de-intercalation in a 1 M LiClO4-propylene carbonate electrolyte by switching measurements with a potential sweep from − 1.25 V to 1.25 V at a scan rate of 50 mV/s, even after being bent 360° around a 2.5 cm diameter rod for 1000 cycles. The Li+ ionic diffusion coefficient and conductivity are respectively of up to 1.2 × 10− 10 cm2/s and 1 × 10− 8 S/cm for LixTaOyCz films synthesized using an APPJ with a certain O2 gases addition of 9 sccm.