Fabrication of efficient and economical dye-sensitized solar cells using carbon-coated nanotextured silicon wafers counter electrodes

Significant progress has been made in various fields of photovoltaics in response to the growing demand for alternative energy resources. Silicon technologies dominate the current solar cell market, but carbon-based photovoltaics are known for their ability to be produced at low cost and in large quantities. The electrocatalyst accelerates the conversion of tri-iodide into iodide ions at the interface between the counter electrode and the electrolyte, according to DSSC principle. During the catalytic process, the accessible sites for the reaction between the reactants and the catalyst are greatly influenced by the surface area and morphology of the counter electrode and electrocatalyst. Therefore, in this work, silicon micro cubes with different patterns were fabricated using lithography, and a carbon layer has been coated directly using chemical vapor deposition on the surface of silicon samples with 15, 30, and 60 mins growth times. The functionalized silicon surface with the carbon layer subsequently demonstrated electrocatalytic activities for iodide/triiodide reduction. In DSSCs, the carbon-coated samples have been utilized as counter electrodes. The samples were characterized using Raman spectroscopy and scanning electron microscopy. DSSCs were fabricated for each synthesized counter electrode, and DSSCs performance has been analyzed for each DSSC. Utilizing carbon-coated nanotextured silicon wafers as the counter electrodes, DSSCs were able to achieve the maximum power conversion efficiency of 6.73%. The current results pave the way toward the replacement of expensive Pt-based conventional DSSCs.