Photocurrent–Voltage of a Dye-Sensitized Nanocrystalline TiO2 Solar Cells Influenced by N719 Dye Adsorption Properties

Titanium particles of single-phase anatase nanocrystallites were prepared by the hydrolysis of titanium tetraisopropoxide. A dye-sensitized solar cell (DSSC) was fabricated by adsorbing cis-bis(isothiocyanato)bis(2,2′-bipyridyl-4,4′-dicarboxylato)-ruthenium(II)bis-tetrabutylammonium dye (N719) onto TiO2 film. The samples were characterized by XRD, TEM, FE-SEM, AFM, and Brunauer-Emmett-Teller (BET) analysis. The influence of the acetic acid treatment of TiO2 electrode with different concentrations on the photovoltaic performance of DSSC was investigated. It was found that DSSC had better photoelectric performance when the TiO2 electrode was treated by acetic acid of 0.5 M. An equivalent circuit analysis using the one-diode model was used to evaluate the influences of adsorption quantity and acetic acid treatment on the energy conversion efficiency of DSSC. A nonlinear least-square optimization method was used to determine five model parameters.

Download Full-text

Acid-Alkaline Treatment of Mordenite and Its Catalytic Activity in the Hydrotreatment of Bio-Oil

Indonesian Journal of Chemistry ◽

10.22146/ijc.51496 ◽

2020 ◽

Vol 21 (1) ◽

pp. 37

Author(s):

Febi Yusniyanti ◽

Wega Trisunaryanti ◽

Triyono Triyono

Keyword(s):

Acetic Acid ◽

Catalytic Activity ◽

Surface Area ◽

Acid Treatment ◽

Room Temperature ◽

Alkaline Treatment ◽

Bet Analysis ◽

Bio Oil ◽

Acetic Acid Treatment ◽

Xrd Patterns

Acid-alkaline treatment using acetic acid and sodium hydroxide (NaOH) were applied on mordenite (MOR) to increase the Si/Al ratio and surface area properties. Various time treatment (3, 6, and 9 h) and concentration of acetic acid (6, 9, and 12 M) were used to treat MOR, and followed by the treatment with NaOH (0.1 M) under room temperature. The MOR and treated mordenite were applied as a catalyst for hydrotreatment of cellulose-derived bio-oil. The acetic acid treatment caused the increase of the Si/Al ratio of mordenite up to 27.03. The Si/Al ratio was determined using ICP-AES analysis which was also confirmed using FT-IR analysis. The acidity was determined using NH3 vapors adsorption. The acidity test revealed that as the Si/Al ratio increased the acidity of mordenite decreased. The advantage of using acetic acid for acid treatment was that the XRD patterns of mordenite can be preserved with a little decrease of the intensity. On the other hand, the NaOH treatment under room temperature decreased the crystallinity down to 68%, which was calculated using XRD. The acid-alkaline treatment of mordenite succeeded to increase the surface area 2 times larger than the parent mordenite. The surface area was obtained from BET analysis. The acid-alkaline treated mordenite exhibited better catalytic activity upon hydrotreatment of biomass-derived bio-oil compared to the parent mordenite which corresponded to its highest surface area.

Download Full-text

Eco-Friendly Dye-Sensitized Solar Cells Based on Water-Electrolytes and Chlorophyll

Materials ◽

10.3390/ma14092150 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2150

Author(s):

Ji-Hye Kim ◽

Sung-Yoon Park ◽

Dong-Hyuk Lim ◽

So-Young Lim ◽

Jonghoon Choi ◽

...

Keyword(s):

Solar Cells ◽

Plasma Treatment ◽

Ruthenium Complex ◽

Photovoltaic Performance ◽

Dye Sensitized Solar Cells ◽

Dye Adsorption ◽

Synthesis Process ◽

Dye Sensitized ◽

Water Based ◽

Sensitized Solar Cells

Organic solvents used for electrolytes of dye-sensitized solar cells (DSSCs) are generally not only toxic and explosive but also prone to leakage due to volatility and low surface tension. The representative dyes of DSSCs are ruthenium-complex molecules, which are expensive and require a complicated synthesis process. In this paper, the eco-friendly DSSCs were presented based on water-based electrolytes and a commercially available organic dye. The effect of aging time after the device fabrication and the electrolyte composition on the photovoltaic performance of the eco-friendly DSSCs were investigated. Plasma treatment of TiO2 was adopted to improve the dye adsorption as well as the wettability of the water-based electrolytes on TiO2. It turned out that the plasma treatment was an effective way of improving the photovoltaic performance of the eco-friendly DSSCs by increasing the efficiency by 3.4 times. For more eco-friendly DSSCs, the organic-synthetic dye was replaced by chlorophyll extracted from spinach. With the plasma treatment, the efficiency of the eco-friendly DSSCs based on water-electrolytes and chlorophyll was comparable to those of the previously reported chlorophyll-based DSSCs with non-aqueous electrolytes.

Download Full-text