The present work focuses on a comprehensive investigation of charge and thermal transport properties of thallium-indium-based ternary dichalcogenides with a common chemical formula of Tl+(In3+X2
2-)- where X denotes selenium and sulfur atoms. Two compounds in the one-dimensional chain form including pristine TlInSe2 and Fe-doped TlInTe2 as well as a hybrid material constructed from the two-dimensional TlInS2 layered semiconductor diluted with TlFeS2 chain one with 0.7 at. percentage have been successfully grown by the Bridgman-Stockbarger technology. X-ray powder diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy measurements were performed to characterize the local structure and chemical composition features of all prepared compounds. A strong anisotropy in the charge-carrier transport properties of the samples has been observed on dc- and ac- electrical conductivity measurements performed at the geometries parallel and perpendicular to the layers/chains. This is a fundamental property for realizing high thermoelectric performance in semiconducting materials. As a result, extremely large Seebeck coefficients were revealed upon experimental investigations of the thermoelectric properties of Tl+(In3+X2
2-)- samples over wide temperature ranges of between ~ 100 K and ~ 800 K. 
 The first principles density functional theory (DFT) and Boltzmann transport equations (BTE) were employed to investigate the thermal transport properties of the compounds studied at the atomic scale. A specific interaction between thallium cation and sulfur anion was observed within the DFT computation scheme. The developed interaction (more electrostatic than a much weaker the van der Waals one) enhances the charge carriers effective mass via flattening of the electronic bands near the band edges and can give a new path toward the Seebeck coefficient enhancement in the traditional mid-temperature range.