Refining of red spinach extract for the enhanced photovoltaic performance of natural dye-based DSSC and degradation study

AbstractThis study reports the performance analysis of an organic dye-sensitized solar cell (DSSC), introducing MnO2 as an electron transport layer in TiO2/MnO2 bilayer assembly. The DSSCs have been fabricated using TiO2 and TiO2/MnO2 layer-by-layer architecture films onto fluorine-doped tin oxide (FTO) glass and sensitized with natural dye extracted from Malvaviscus penduliflorus flower in ethanol medium. The counter electrode was prepared to layer copper powder containing paste onto FTO's conductive side by the doctor's blade method. The optical, morphological, and structural properties of photoanodes were explored via ultraviolet–visible, field emission scanning electron microscopy, and X-ray diffraction analyses. Moreover, dye complexity and thermostability of dyes were characterized via Fourier-transform infrared spectroscopy and thermogravimetric analyses. The iodide/triiodide (i.e., I−/I3−) redox couple of electrolyte solution was employed as a charge transport medium between the electrodes. Finally, photoanode and counter electrode sandwiches were assembled to envisage the photovoltaic performance potential under simulated AM 1.5G solar illumination using 100 mW cm–2 light intensity. The as-fabricated DSSC comprising TiO2/MnO2 bilayer assembly exhibited 6.02 mA cm–2 short circuit current density (Jsc), 0.38 V open-circuit voltage (Voc), 40.38% fill factor, and 0.92% conversion efficiency, which is about 200% higher compared to the assembly devoid of MnO2 layer.

Download Full-text

Sol-Gel Derived ZnO Nanorod Templated TiO2 Nanotube Synthesis for Natural Dye Sensitized Solar Cell

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.896.485 ◽

2014 ◽

Vol 896 ◽

pp. 485-488 ◽

Cited By ~ 3

Author(s):

Indriana Kartini ◽

Evana ◽

Sutarno ◽

Chotimah

Keyword(s):

Electron Microscopy ◽

Solar Cell ◽

Sol Gel ◽

Photovoltaic Performance ◽

Dye Sensitized Solar Cells ◽

Natural Dye ◽

Zno Nanorod ◽

Solar Cell Performance ◽

Enhanced Absorption ◽

Dye Sensitized

Natural dye sensitized solar cells (nDSSC) mostly suffer from low solar cell performance, that vertically aligned nanotube TiO2 as the photoanode is expected to increase the performance by providing higher surface area and direct electron transport. Nanostructured TiO2 films have been fabricated on glass substrates employing ZnO nanorod films as the template. First, vertically oriented ZnO nanorod on a glass substrate was prepared hydrothermally. Then, sol-gel dip-coating technique was used to deposit TiO2. The template films were dip-coated into sols of titanium tetraisopropoxide-ethanol-diethanol ammine with withdrawing rate of 2 cm/min for three- (Ti3) and seven-times (Ti7). After drying at 100 °C for 10 min, the films were calcined at 550 °C for 1h and washed with HCl 3% (v/v). The films were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). It is observed that different coating cycles resulted in different film morphologies. Nanotube TiO2 with diameter of ~50 nm was identified for Ti3, while Ti7 displayed sheet-like structure. The diffraction patterns confirmed the presence of only anatase crystalline phase with crystallite size of 10.3 nm (Ti3) and 21.7 nm (Ti7). The dye absorption was red-shifted indicating dye monomeric adsorption on TiO2 via chelation. Enhanced absorption of anthocyanin dye extracted from pericarps of mangosteen (Garcinia mangostana l.) fruit on TiO2 nanotube compared to TiO2 nanoparticle (P25) was observed leading to improved photovoltaic performance of the constructed nDSSC.

Download Full-text

Karakteristik dan Aktivitas Antioksidan Velva Bayam Merah dan Penstabil CMC (Carboxyl Metyl Cellulose)

Food Technology and Halal Science Journal ◽

10.22219/fths.v4i1.15571 ◽

2021 ◽

Vol 4 (1) ◽

pp. 10-22

Author(s):

Vritta Amroini Wahyudi ◽

Winda Cancerina Harsono Putri ◽

Elfi Anis Saati

Keyword(s):

Vitamin C ◽

Vegetable Consumption ◽

Ice Cream ◽

Natural Dye ◽

Anthocyanin Content ◽

Low Fat ◽

Mineral Salts ◽

Group Design ◽

Spinach Extract ◽

Red Color

Red spinach is known as a food stuff for protein, vitamins A, B, and C and contains mineral salts. Red spinach is used as a natural dye because it is thought that red spinach has betacyanin and anthocyanin content that can produce a purpleish red color. Efforts to increase vegetable consumption are carried out by modifying as a velva, a frozen beverage product that are almost the same as low-fat ice cream Velva. The purpose of this study is to know the interaction of the addition of red spinach extract and CMC stabilizing material, to know the influence of red spinach concentration, and to know the influence of differences in cmc concentrations on Velva characteristics. The implementation of the experiment used a Randomized Group Design (RAK) that was factorially arranged consisting of 2 factors. Factor 1 is the concentration of red spinach extract consisting of 3 levels namely 20%, 25%, and 30% while factor 2 is CMC concentration consisting of 3 levels which is 0.5%, 0.75%, and 1%. Observation parameters include vitamin C levels, melting power, viscosity, antioxidants, anthocyanins, and organoleptics that include color, aroma, taste, texture, and fondness. The results showed that red spinach extract had a significant effect on antioxidants with the greatest value in B3 treatment (Spinach Extract 30%) 53.70%; vitamin C with the greatest value in B3 treatment (CMC 1%) 6.3 g/mL, and anthocyanins with the best 3 treatments are B3 at 1.1675 mL/L, while CMC has a significant effect on melting power, viscosity, and vitamin C Velva spinach red. The results showed that red spinach Velva contains a small amount of glycine so that the pigment contained is betacyanin.

Download Full-text