Ruthenium oxide modified titanium dioxide nanotube arrays as carbon and binder free lithium–air battery cathode catalyst

RuO2 modified TiO2 nanotube arrays, growing on Ti foams, are used as carbon and binder free cathodes for Li–O2 batteries. The micrometer pores in Ti foams and nanometer pores in TiO2 nanotubes supply facilitated transport channels for oxygen diffusing into/out of the catalysts in discharge and charge processes. The RuO2 catalyst exhibits outstanding catalytic active toward oxygen evolution reaction (OER), which leads the charge voltage maintaining around 3.7 V all through the battery cycling. The stability of TiO2/Ti support, abundant oxygen transport path and favorable catalytic activity of RuO2 toward OER enable the Li–O2 batteries exhibiting 130 cycle discharge/charge. •Carbon and binder free Li–O2 battery cathodes constructed by a bottom-up method.•RuO2 catalyst on a stable TiO2 nanotube array catalyst support.•More than 100 cycle charge/discharge.