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A. Dey et al.
wide bandgap. This sensitized light plays an important role for generating electrical energy through absorbing light from the sun and transforming it into energy.
Among various inorganic dyes, Ru-based complex sensitizer is widely used due
to their better photo conversion efficiency and high durability. But it possesses
some demerits—their high cost, complicated synthetic routes, and lean towards
degradation in presence of water (Zhang et al. 2008). In recent days, using natural
pigments in the form of sensitizer for generating electricity has been started due to
their various utilities—it is cost friendly as it is occurred naturally and also environmentally friendly (Kay and Graetzel 1993). Presently using of natural organic
days in DSSC as sensitizer has become a new trend. In one of the previous works
extracted, catechins from green tea leaves that have been used as sensitizer in DSSC
(Dey et al. 2016) resulted improved photo conversion efficiency. Dey et al. (2017a)
describes the photoconversion result of TiO 2 doped with graphene in association
with bilayer of CdS. Whereas Dey et al. (2017b) describes the improved conversion
efficiency observed for quantum dot solar cell, post addition of synthesized dielectric
material lanthanum-doped lead titanate (PLT15).
In this paper, we report the performance improvement of DSSC through addition
of synthesized dielectric material within the TiO 2 mesoporous film. The used dielectric material in this work is lanthanum-doped lead titanate (PLT15) due to its various
beneficial factors: strong field–effect passivation, screened columbic attraction, back
reflector, and recombination inhibitor for solar cell. Additionally, for the sensitization natural dye, carotene was extracted using carrot as rich source. The extraction
involved three-step processes. Initially the chopped samples underwent for drying.
Further the dried samples were grinded in the form of fine particles and finally the
dye solution was prepared in presence of solvent. The fabrication of DSSC was then
carried out using synthesized dielectric material within the TiO 2 matrix and hence
the performance testing and other characterizations were carried out.
2 Experimental Details
2.1 Synthesis of TiO 2 Nanoparticles
Under continuous stirring of 0.1 M nitric acid solution, 5 ml of titanium isopropoxide
(97% Sigma-Aldrich) was added dropwise at room temperature. Soon a white precipitate was generated that was heated at 80 °C. Further, at 1000 rpm stirring was
continued for 8 h for achieving peptization. Then, nonpeptized agglomerates were
removed through centrifugation at ∼2000 rpm. Then by adding water to it, the final
concentration was obtained as ∼5 wt%. The solution was transferred to an autoclave. For 12 h, the stainless steel makes autoclave lined with Teflon was heated
at 230–250 °C for the desired growth of 10–25 nm particles. Finally, the colloidal
suspension was concentrated by employing of heating at 70 °C for 1 h.
A. Dey et al.
wide bandgap. This sensitized light plays an important role for generating electrical energy through absorbing light from the sun and transforming it into energy.
Among various inorganic dyes, Ru-based complex sensitizer is widely used due
to their better photo conversion efficiency and high durability. But it possesses
some demerits—their high cost, complicated synthetic routes, and lean towards
degradation in presence of water (Zhang et al. 2008). In recent days, using natural
pigments in the form of sensitizer for generating electricity has been started due to
their various utilities—it is cost friendly as it is occurred naturally and also environmentally friendly (Kay and Graetzel 1993). Presently using of natural organic
days in DSSC as sensitizer has become a new trend. In one of the previous works
extracted, catechins from green tea leaves that have been used as sensitizer in DSSC
(Dey et al. 2016) resulted improved photo conversion efficiency. Dey et al. (2017a)
describes the photoconversion result of TiO 2 doped with graphene in association
with bilayer of CdS. Whereas Dey et al. (2017b) describes the improved conversion
efficiency observed for quantum dot solar cell, post addition of synthesized dielectric
material lanthanum-doped lead titanate (PLT15).
In this paper, we report the performance improvement of DSSC through addition
of synthesized dielectric material within the TiO 2 mesoporous film. The used dielectric material in this work is lanthanum-doped lead titanate (PLT15) due to its various
beneficial factors: strong field–effect passivation, screened columbic attraction, back
reflector, and recombination inhibitor for solar cell. Additionally, for the sensitization natural dye, carotene was extracted using carrot as rich source. The extraction
involved three-step processes. Initially the chopped samples underwent for drying.
Further the dried samples were grinded in the form of fine particles and finally the
dye solution was prepared in presence of solvent. The fabrication of DSSC was then
carried out using synthesized dielectric material within the TiO 2 matrix and hence
the performance testing and other characterizations were carried out.
2 Experimental Details
2.1 Synthesis of TiO 2 Nanoparticles
Under continuous stirring of 0.1 M nitric acid solution, 5 ml of titanium isopropoxide
(97% Sigma-Aldrich) was added dropwise at room temperature. Soon a white precipitate was generated that was heated at 80 °C. Further, at 1000 rpm stirring was
continued for 8 h for achieving peptization. Then, nonpeptized agglomerates were
removed through centrifugation at ∼2000 rpm. Then by adding water to it, the final
concentration was obtained as ∼5 wt%. The solution was transferred to an autoclave. For 12 h, the stainless steel makes autoclave lined with Teflon was heated
at 230–250 °C for the desired growth of 10–25 nm particles. Finally, the colloidal
suspension was concentrated by employing of heating at 70 °C for 1 h.