Enhanced Stability of Pt-TiO2-CNT Heterostructure Composite Cathodes for Li-O2 Batteries Studied by High-Resolution AEM
Vladimir P. Oleshko
Li-O2 batteries currently attract a lot of attention due to their super-high theoretical specific energy (~3500 Wh kg-1), which is almost an order of magnitude higher than for any Li-ion batteries (~380 Wh kg-1). Combined with the ability to use ambient oxygen as a fuel, Li-O2-based rechargeable electrochemical batteries show high promise in emerging pollution-free applications for long-range electric vehicles (>550 km) and in stationary grid energy storage. One of the obstacles for the practical realization of Li-O2 battery technology is, however, poor (electro)chemical stability of a cathode material under cell operating conditions. High surface area carbon-based cathodes have been shown high gravimetric capacities, but are hindered in terms of long term stability due to the reactivity of the carbonaceous electrode. In this work, we demonstrate using high-resolution analytical scanning/transmission electron microscopy (AS/TEM) that conjugation of effective protection and subsequent catalytic functionalization of the carbon surface provides a pathway toward harnessing the excellent current collector properties and high surface area of the carbon scaffold without risking known reactivity issues.
Microscopy and Microanalysis
Li-O2 battery materials, ALD, heterostructures, high-resolution analytical electron microscopy