Ink formulation and 3D Printing: VS2 inks were formulated by dispersing carbon black (acetylene, 100% compressed, Alfa Aesar) in dimethyl sulfoxide (DMSO) at 10wt% using a planetary mixer (Thinky ARE-250) at 1800 rpm for 2 min. Polyvinylidene fluoride (PVDF) was subsequently added to the mixture (PVDF:carbon black 1:1 weight ratio) and the resulting slurry was homogenized further 2 min at 1800 rpm. Finally hydrothermal VS2 was ground in an agate mortar and added the slurry, which was again homogenized for 2 min at 1800 rpm. The final composition of the ink was 6:2:2 (VS2:PVDF:carbon black) by mass. The conductivity of the carbon black slurries was measured with 4-probe tests using a Gamry Interface 1000 galvanostat. The rheological properties of the VS2 ink were measured on a rotational rheometer (Discovery Hybrid Rheometer HR1 -TA Instruments) equipped with stainless-steel parallel plates (40 mm in diameter). Oscillatory stress sweeps were performed at a fixed frequency of 1 Hz, while oscillatory recovery tests were performed at 10 Hz to maximize the acquisition of points over time. Oscillatory frequency sweeps were conducted at a fixed strain amplitude of 0.1%, within the linear viscoelastic region of the VS2 inks, as determined from the oscillatory stress sweeps. The inks were printed using an extrusion 3D printer with displacement-controlled plungers, at a feed rate of 6 mm s -1 and through 410 μm nozzles. After printing the electrodes were dried overnight at room temperature.