With the goal of applying them in organic photovoltaics (OPVs), in this study we synthesized two organometallic alternating conjugated polymers, TPT-TPyPt and TPT-TIqPt, consisting of indacenodithiophene (thiophene/phenylene/thiophene; TPT) and cyclometalated platinum(II) moieties and compared their optical, electrochemical, and photovoltaic properties, their space charge limited currents, and their structures (density functional theory) with those of related platinum-free organic polymers, TPT-TPy and TPT-TIq. The absorption bands of the metal-based polymers were significantly red-shifted relative to those of the metal-free polymers. We fabricated OPVs incorporating blends of these polymers and [6,6]-phenyl-C-71-butyric acid methyl ester at various weight ratios. One of these devices exhibited a power conversion efficiency (PCE) of 2.9%, with a short-circuit current density of 7.7 mA/cm(2), an open-circuit voltage of 0.78 V, and a fill factor of 0.48, under AM 1.5 G (100 mW/cm(2)) illumination. To the best of our knowledge, this PCE is the highest reported for a PSC based on a cyclometalated platinum-type polymer. (C) 2012 Elsevier B.V. All rights reserved.