A new method for fabrication of highly transparent Pt counter electrodes (CE) has been developed based on spray deposition of Pt nanoparticles (Pt-NPs) on hot substrates. The platinum consumption hence the cost of the counter electrode was reduced over 86%, compared to conventional Pt counter electrode prepared by sputter deposition method. The prepared Pt-NP film led to 89% transparency and 80% transparency when integrated with indium tin oxide/glass substrate. DSSCs with Pt-NP counter electrode had 6.17% power conversion efficiency, comparable to the 6.46% efficiency of the corresponding...