Carbon nanostructures (CNTs) have been prepared by a Hydrothermal deposition technique based on the polymer Polyethylene glycol (PEG) dissolved in water and Ethanol alcohol of a new carbon sources materials mixed with (PdCl2) as a catalyst mixed with Sodium hydroxide (8gm NaOH) using Parr reactor at temperature (190°C) and forming the hybrid composite material (TiO2/Pd/MWCNTs) by the same way. Thence, deposited heterojunction material (TiO2/Pd/MWCNTs:n-Si) using the Pulsed Laser Deposition Technique (PLD), on the substrate of n-silicon wafer. The obtained (MWCNTs & TiO2/Pd/MWCNTs) are investigated by scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray Photo-electron Spectroscopy (XPS). Normal MWCNTs are formed multi-walled carbon nanotubes (MWCNTs) and carbon nanosheets (CNSs) but in little bit amount. MWCNTs were obtained as main products with lengths of (1.6–3 μm) and diameters of (30-60 nm) could be synthesized at as low temperature as (190°C). Deconvolution of the (C1s ) peaks which characteristic of C-C bonds, showed a main peak at (284.96 and 285.04 eV) with total amount (74.96 and 30.64 at%) for the product of MWCNTs and TiO2/Pd/MWCNTs composite respectively. Current – voltage characteristics of heterojunction showed that forward bias current change exponentially approximately with applied voltage at dark and this agreement with tunneling–recombination model. Also (I-V) characteristics under illumination of TiO2/Pd/MWCNTs heterojunction deposited on p-Si substrate (η=10.5) efficiency in Solar Cell.