Ta-8(mu(3)-O)(2)(mu-O)(8)(mu-OEt)(6)(OEt)(14) (1) was obtained by the controlled hydrolysis of tantalum ethoxide Ta(OEt)(5) in the presence of ammonia. Compound 1 is considered as the intermediate building block in the sol-gel polymerization of Ta(OEt)(5). Further hydrolysis of compound 1 yielded nanoparticles of Ta2O5, which were characterized by various techniques such as TGA-DTA-DSC, UV-vis DRS, XRD, SEM, TEM, particle size analyzer (DLS) and the Brunauer-Emmett-Teller (BET) method. The band gap of the particles was calculated by using the Tauc plot. The photocatalytic activity of Ta2O5 nanoparticles was tested by the degradation of the organic dye rhodamine B.