  Capacitive Deionization (CDI) is a non-energy intensive water treatment
technology. To harness the enormous potential of CDI requires improving
performance, while offering industrially feasible solutions. Following this
idea, the replacement of costly metallic components has been proposed as a mean
of limiting corrosion problems. This work explores the use of nanostructured
hybrid networks to enable free-form and metal-free CDI devices. The strategy
consists of producing interpenetrated networks of highly conductive flexible
carbon nanotube (CNT) fibre fabrics and nanostructured metal oxides,
{\gamma}Al2O3 and TiO2, through ultrasound-assisted nanoparticle infiltration
and sintering. In the resulting hybrids, a uniform distribution of porous metal
oxide is firmly attached to the nanocarbon network while the flexibility, high
conductivity and low-dimensional properties of the CNTs are preserved. These
electrodes present a high porosity ($105 - 118 m^{2} g^{1}$), notably low
electrical ($< 0,1 k \Omega cm^{2}$) and low charge transfer resistance (4
{\Omega}), thus enabling the infiltration of aqueous electrolytes and serving
as current collector. In this work we built a large asymmetrical cylindrical
CDI device solely made of these electrodes and conventional plastics. The cell
provides, high average salt adsorption rates of $1.16 mg /g_{AM} min$ ($0.23
mg/g_{CDIunit} min$, low energy consumption ($0.18 Wh/g_{salt}$) and stable
electrochemical performance above 50 cycles for brackish water desalination.
