The pulsed laser deposition (PLD) technique is used for the direct fabrication of nanohybrid heterojunctions (NH-HJs) solar cells exhibiting high PCE and excellent stability in air without any encapsulation and/or resorting to any surface treatment, ligand engineering and/or post-synthesis processing. The NH-HJs are achieved through the PLD-based decoration of hydrothermally-grown one-dimensional TiO2 nanorods (TiO2-NRs) by PbS quantum dots (PbS-QDs). By optimizing both the amount of PbS-QDs (via the number of laser ablation pulses) and the length of the TiO2-NRs, it is possible to achieve optimal NH-HJs based PV devices with high power conversion efficiency (PCE) of 4.85%. This high PCE is found to occur for an optimal length of the NRs (≈290 nm) which coincides with the average penetration depth of PbS-QDs into the porous TiO2-NRs matrix, leading thereby to the formation of the largest extent of NH-HJs. Most importantly, the PCE of these novel devices is found to be fairly stable for several months under ambient air. The addition of single-wall carbon nanotubes (SWCNTs) onto the TiO2-NRs prior to their decoration by PbS-QDs is shown to further enhance their PCE to a value as high as 5.3%, because of additional light absorption and improved charge collection ensured by SWCNTs.