Redox-active pigeon excreta mediated metal oxides nanosheets for enhancing co-catalyst for photovoltaic performance in dye-sensitized solar cells

Pigeon excreta (PE) contains a significant amount of organic components, which are harmful to the environment and humans. Hence, the proper disposal of PE deals with practical problems. Furthermore, using PE for other energy sources is an efficient innovation. In this study, an innovative technique was implemented for producing agglomeration free and distinct metal oxides using PE as a surfactant and capping agent. The different characterizations and their analysis explain the mechanism involved in forming distinct metal oxide nanosheets utilizing PE. The obtained samples were confirmed by the characteristic peaks of PE mediated metal oxides such as (NiO, Co3O4 and CuO) observed in X-ray diffraction (43.47 degrees, 36.61 degrees and 35.71 degrees), and the UV-DRS band-gap narrowing (2.4, 2.13 and 2.02 eV). In the FTIR spectrum, it is clearly evident that there is a high amine group in the PE which plays a key role in reducing the agglomeration in the metal oxides. The morphology of PE mediated NiO, Co3O4 and CuO revealed nanoflakes and nanosheets like structures identified from FE-SEM analysis. The photovoltaic performance of the PE mediated metal oxides showed improved photocurrent conversion efficiencies of 1.2-1.6 times more than pure metal oxides. Among all, the CuO-PE had the most significant photovoltaic performance, with a photoconversion efficiency of 3.22 %. The reduction of I-3(-) to 3I(-) along the counter electrode/electrolyte interaction is facilitated by the PE mediated transition metal oxides, as shown by the photocurrent response, Tafel plot and electrical impedance spectroscopy results, which were discussed in detail.

Automated summary

In this study, an innovative technique was used to produce agglomeration free and distinct metal oxide nanosheets using pigeon excreta as a surfactant and capping agent. The different characterizations and analyses explained the mechanism involved in forming these nanosheets. The metal oxides mediated by pigeon excreta showed improved photovoltaic performance compared to pure metal oxides.