Unraveling the influence of incorporating transition metal elements on layered transition metal chalcogenides for energy storage application remains a challenge. Herein, niobium (Nb)-doped layered titanium disulfide (TiS2) is applied to generate novel compounds Ti1−xNbxS2 (x=0.05, 0.1 and 0.20). Interestingly, TiS3 nanobelts are formed in the resulting materials, which is proven by systematic morphological and structural characterization. It has been found that Nb-doped TiS2 compounds demonstrate superior electrochemical capacitive activity, reaching up to a 63.2 % increase in gravimetric capacitance in 1 M Na2SO4 electrolyte compared with that of the Nb-free TiS2. This remarkably enhanced capacity behavior is attributed to Nb doping resulting a structural transition of Layered TiS2 to TiS3 nanobelts.