Synthesis of photoactive Polyoxometalate-porphyrin hybrids to trigger the photocurrent by designing the ultra-thin films

Abstract

In this work, two new, efficient, and ecofriendly hybrids based on Polyoxometalates-porphyrin namely CuAnPOM@3PhP, and LPOM@3PhP have been synthesized and characterized through FT-IR, UV–Visible, Elemental analysis, fluorescence studies, 1HNMR, and cyclic voltametric analysis to utilize its use in the light conversion devices by designing their thin films based on titanium dioxide. The titanium dioxide based thin films of CuAnPOM@3PhP, and LPOM@3PhP have been designed by using dr. Blade method. Based on Swanepoel's envelops method different optical parameters of CuAnPOM@3PhP, and LPOM@3PhP thin films has been investigated by using their transmission spectra at room temperature. The electrical conductivity of LPOM@3PhP (2.2 × 103 to −4.6 × 103 S/m) is found to be higher than that CuAnPOM@3PhP (2.0 × 101−4.2 × 101 S/m). This more enhancement in electrical conductivity of LPOM@3PhP is attributed to its more fluorescence quenching (more photoinduced transfer of electrons from porphyrin moiety to L-POM), and low band gap energy. However, the dielectric loss is found to be less in both of CuAnPOM@3PhP, and LPOM@3PhP ultra-thin films that points its remarkable use in opto-electronic devices. The photocurrent generation has been studied by using two-probe multimeter. During measurement of photocurrent generation, it has been analyzed that LPOM@3PhP show more energy losses as compared to CuAnPOM@3PhP. However, during photocurrent generation the persistent of negative photoconductivity in ultra-thin films of CuAnPOM@3PhP, and LPOM@3PhP make them an excellent candidate to be utilized in optoelectronic devices such as solar cell, and photovoltaic cell etc.