Excited State Of Dye Research Articles

Efficiency enhancement of natural cocktail dyes in a TiO2-based dye-sensitized solar cell and performance of electron kinetics on the TiO2 surface

In this study, natural dye extracts were prepared from the dried leaves of Andrographis paniculata and Psidium guajava (APPG). The study’s objective was to increase the light harvesting phenomenon from solar energy utilizing natural dye from APPG, and the problem statement was to harvest the optimum solar radiation and convert it into electrical energy. Acetone and ethanol were used as solvents during the preparation process. Based on this research, the crystallite size of TiO2 nanoparticles was assessed, the impact of acetone and ethanol on APPG dye was compared, and the absorption, FTIR, and UV-Vis spectra of the solar cell fabrication process using solvents were experimentally explored. APPG leaf extract functions as a dye sensitizer. Cells are precisely sandwiched with a photoanode, TiO2 nanoparticles, an electrolyte (I/I3−), and a cathode. The JV properties of dye extracts utilizing acetone and ethanol were measured using a solar simulator equipped with a 100 mW/cm2 Xenon light and a Keithley 2400 Graphical Series SMU. An experimental DSSC with dye extraction and utilizing acetone solvent yielded a maximum photo-conversion efficiency of 0.6914%, while ethanol yielded a photo-conversion efficiency of 0.5630%. Furthermore, an energy-level diagram was used to explain the electron kinetics of DSSC, and the time required for transfer electron injection in the TiO2 surface from a dye-excited state was 150 ps.

DFT Study of New Donor-π-Acceptor Materials Based on Thieno[2,3-b] Indole Candidate for Organic Solar Cells Application

In present search, we report theoretical analysis by using DFT (TD-DFT)-B3LYP with 6-31G (d, p) level on the geometries, optoelectronic and absorption characteristics of novel a series of the donor-π-acceptor dyes. Their π-conjugated bridge is based on the thiophene, benzene, pyridine, and pyrazine, the thieno [2,3-b] indole was used as an electron donor (D) and the acid 2-cyanoacrylic was used as an electron acceptor (A) group. The theoretical information of the electronic structures such as energy levels (HOMO and LUMO) and energy gap of the molecules is based on study the dyes in organic solar cells. Consequently the energy levels, energy gap, photovoltaic properties, quantum chemical and absorption parameters of all the dyes have been computed and reported. The calculations show that the dyes under study can theoretically be good photosensitizers in DSSCs. Also, the results show that the LUMO levels of all dyes design lie over the conduction band (Ecb) of the semiconductors TiO2 (or PC70BM) likewise the HOMO levels lie under the decrease potential vitality of the (electrolytes) comparing to ability of electron transfer from the molecular dye excited state to TiO2 (or PC70BM) and chargeerenewal after photo-oxidation process, separately.

Concerted Photoluminescence of Electrochemically Self-Assembled CuSCN / Stilbazolium Dye Hybrid Thin Films

Whether they are inorganic or organic, the key words for creation of new functional materials should be (1) solution, (2) low temperature, and (3) rare-element-free for sustainable development. As a leading example, we explore electrochemical self-assembly (ESA) of inorganic / organic hybrid thin films. In addition to the interests to study evolution of unique hybrid structures, concerted new functionalities are anticipated due to intimate interaction between the inorganic and organic constituents. Herein, we report ESA of CuSCN / 4-(N,N-dimethylamino)-4’-(N’-methyl)stilbazolium (DAS) hybrid thin films and its concerted photoluminescence (PL) behavior [1]. Hybrid thin films of crystalline CuSCN/DAS in three distinctively different nanostructures were obtained by ESA from a single pot containing all the chemical ingredients. Adsorption of DAS during the electrochemical precipitation of CuSCN result in significant change of film morphology, crystal structure and its orientation, as DAS “occluded” into crystal grains of β-CuSCN, DAS phase separated nano-“haircomb” shape β-CuSCN, and DAS phase-separated in nano-“scale” shape α-CuSCN, by simply increasing DAST concentration in the bath [2]. Their optical properties for UV-vis-NIR absorption, photoluminescence (PL), and PL excitation (PLE) spectra were examined between 77 and 298 K, in comparison with solution and solid powder of DAS tosylate (DAST). While all the fluorescent dyes we previously found to hybridize with CuSCN underwent quenching due to hole injection from dye excited state to the valence band of CuSCN, DAS presented the first and only example to exhibit PL when combined with CuSCN [3]. DAST exhibited a strong exciton-phonon coupling to weaken, broaden, and red shift PL at room temperature, so that it inversely is strongly enhanced, sharpened, and blue-shifted at 77 K. However, the PL of the same dye in the hybrid thin film shows a slight red shift and not much intensified. Dielectric environment as well as ordered alignment of DAS greatly stabilize exciton against thermalization loss by suppressing twisted intramolecular charge transfer (TICT) and exciton-phonon coupling. The smallest temperature dependence, thus to be interpreted as the strongest exciton stabilization, was found for the “haircomb” β-CuSCN/DAS hybrid. The PLE spectra of the “scale” α-CuSCN/DAS hybrid show a prominent sharp peak at 380 nm and another double-peak between 400 and 450 nm by cooling temperature. The former corresponds to the band-edge absorption of CuSCN, while the latter being similar to the LMCT absorption of [Cu(SCN)]+ complex. It has been confirmed that those peaks in PLE spectra indicate the contribution of CuSCN thin film without DAS for the generation of PL. These contributions of the light absorption by CuSCN to the PL from DAS clearly indicate energy transfer from CuSCN to DAS as a concerted PL mechanism. Concerted PL by energy transfer from CuSCN to DAS has also been found to occur efficiently, especially for the “scale” α-CuSCN/DAS with the largest contact area due to interpenetrating hybrid nanostructure in the smallest domain size. Those hybrid thin film having the concerted PL mechanism (Fig. 1) can possibly make these materials useful as LEDs.[1] K. Uda et al., ACS Omega, 2019, 4 (2), 4056-4062.[2] Y. Tsuda et al., Chem., 2017, 148, 845-854.[3] K. Uda et al., ECS Trans., 2019, 88, 323-333. Figure 1

Reversible Charge Transfer with Single-Walled Carbon Nanotubes Upon Harvesting the Low Energy Part of the Solar Spectrum.

Here, the ability of a novel near-infrared dye to noncovalently self-assemble onto the surface of single-walled carbon nanotubes (SWCNTs) driven by charge-transfer interactions is demonstrated. Steady-state, Raman, and transient absorption spectroscopies corroborate the electron donating character of the near-infrared dye when combined with SWCNTs, in the form of fluorescence quenching of the excited state of the dye, n-doping of SWCNTs, and reversible charge transfer, respectively. Formation of the one-electron oxidized dye as a result of interactions with SWCNTs is supported by spectroelectrochemical measurements. The ultrafast electronic process in the near-infrared dye, once immobilized onto SWCNTs, starts with the formation of excited states, which decay to the ground state via the intermediate population of a fully charge-separated state, with characteristic time constants for the charge separation of 1.5 ps and charge recombination of 25 ps, as derived from the multiwavelength global analysis. Of great relevance is the fact that charge-transfer occurs from the hot excited state of the near-infrared dye to SWCNTs.

Novel far UV–Vis absorbing bis(dihydrophenanthro[9,10-e][1,2,4]triazine) derivative dyes: Synthesis, optical, photophysical and solvatochromic properties

In this paper discussed novel fluorescent derivative dye in far UV–Vis range have been synthesized by bis-alkylation of starting compound 4, 12a-dihydrophenanthro [9, 10-e][1, 2,4]triazine-3(4H)-thione, with the appropriate dibromo compounds. and characterized by standard spectroscopic techniques. Their chemical structures were confirmed by 1HNMR, IR, MS and elemental analysis. Various optical characterizations were carried out in solvents of varying polarity. Optical parameters via extinction coefficient, absorption and emission cross-sections, fluorescence quantum yield, fluorescence lifetime, oscillator strength, the dipole moment, radiative decay rate constant, energy yield of fluorescence and the attenuation length has been determined. The effect of the spacer between two phenanthro[9,10-e][1,2,4]triazine units in new dye and solvent polarities upon the spectral properties are discussed. The ground-state (μg) and excited-state (μe) dipole moments were estimated using solvatochromic correlations. The higher value of Δμ may attribute to the singlet higher excited state of dyes which had strong intramolecular charge transfer character (ICT).

Synthesis, structural/photophysical characterization and theoretical investigations with new β-pyridinium/quinolinium and β-bromine substituted bis(1,3-dimethylbarbituric acid) trimethine oxonol dyes that display large Stokes shifts

An efficient 3-step procedure for the synthesis of novel β-pyridinium/quinolinium/bromine-substituted bis(1,3-dimethylbarbituric acid)trimethine oxonol dyes was developed that involves a simple triethylamine-promoted condensation of 1,3-dimethylbarbituric acid with preformed vinamidinium salts. 1H NMR, 13C NMR, IR and mass spectral data confirmed the structures of the dyes. Solutions of the dyes in CH3CN exhibited absorption and fluorescence emission maxima in the range of 467–480 nm and 531–712 nm, respectively, identifying that the dyes show unusually large Stokes shifts (~230 nm). Investigating the photophysical properties of dye 3a in a series of organic solvents with different polarity confirmed intramolecular charge transfer (ICT). Optimized geometries of the synthesized dyes in the ground state calculated using density functional theory (DFT) at the B3LYP/6-311G(d,p) theory level identified that planar cis and trans configurations were preferred for the pyridinium/quinolinium and bromine substituted dyes, respectively. TD-DFT calculations on the dye excited state structures identified that rotation of the bulky pyridinium substituents during relaxation is responsible for the large Stokes shift. The unique properties of the dyes suggest they could find use as fluorescent visualizers for intracellular imaging.

The photokinetics of phenothiazine dyes with titanium trichloride in different solvents

AbstractThe kinetic parameters of photoinduced electron transfer reaction of two phenothiazine dyes, methylene blue and methylene green with titanium trichloride, were determined in water and different aqueous‐alcoholic solvents at different acidities by using a specially designed optical system. The rate of photoinduced electron transfer reaction was measured by determining the quantum yield of the reaction. The methylene green had a higher reactivity as compared to methylene blue with titanium trichloride. The graphical analysis showed that the reaction of dye with titanium trichloride follows pseudo–first‐order kinetics. A reaction mechanism was proposed by considering the different excited states of dye and their possible interaction with the solvent and titanium trichloride. The different steps in the reaction mechanism were taken into consideration for deriving rate equations, which were used to determine the different rate constants in the reaction mechanism in different solvents.

A combined solvatochromic shift and TDDFT study probing solute-solvent interactions of blue fluorescent Alexa Fluor 350 dye: Evaluation of ground and excited state dipole moments.

Herein we report, the effect of solvents on absorption and fluorescence spectra of Alexa Fluor-350 labelled fluorescent dye examined both experimentally and computationally. The steady state absorption and fluorescence measurements are carried out in a series of solvents to explore their solvatochromism and to determine its dipole moments. To this end, different empirical solvatochromic models like Bilot-Kawaski, Lippert-Mataga, Bakhshiev, Kawaski-Chamma-Viallet and Reichardt models are assessed against Alexa Fluor 350 dye to determine the singlet excited and ground state dipole moments. Computational studies were carried out to optimize ground and excited geometries using density functional theory (DFT) and time dependent density functional theory (TD-DFT), respectively, in vacuum. Additionally, this study encompasses estimation of the electronic transition energies from the ground to first excited state of dye employing TD-DFT. Further, TD-DFT has been combined with integral equation formalism of the polarizable continuum model (IEF-PCM) to calculate various solute-solvent interaction potentials which are then compared with experimental values. The highest occupied molecular orbital energy (HOMO), lowest unoccupied molecular orbital energy (LUMO), the energy gap, chemical hardness (η), softness (σ), electronegativity (χ) and chemical potential (μ) were estimated. Mulliken atomic charge, natural population analysis (NPA) and molecular electrostatic potential (MEP) map are correlated using density functional theory. The experimentally obtained ground and excited state dipole moments are compared with the ones obtained from computational and the results are discussed. NBO analysis is carried out to investigate the intramolecular charge transfer interactions and stabilization energy within the studied molecule.

Engineering a Coiled Coil Protein as pH Sensor

To design our pH sensor, we decided on using an anti-parallel coiled-coil protein. The protein consists of two α-helices connected by a loop, adopting a super-coiled tertiary structure. Designing and engineering of coiled-coil proteins are already parametrized, so length of the helices can be controlled as desired. The approach for our sensor design incorporates the ‘binding coupled to folding’ design-principle with grafting of histidines (H). The partially protonated side chain of histidine has a pKa close to physiological pH and can switch between protonated (general acid) and unprotonated (general base) states. This switching from an aromatic (at higher pH) to positively charged (at lower pH) state, can have a role in (un)stabilizing the folded structure of the protein. We mutated H into the hydrophobic core to manipulate the coiled-coil structure stability, resulting in an intrinsically unstable native state. The protein populates the unfolded state when the concentration of protons is low and as the concentration of protons is increased, the protein ensemble shifts to the folded state. To monitor this transition, we used quenching of fluorescent dye (Atto 655). As the protein folds, photo-induced electron transfer (PET) occurs between the excited state dye and the ground-state of tryptophan (W). Our results show quenching of about 80% of florescence intensity as the pH is lowered from 8-4, also corroborating our circular dichroism studies.

Coupling of the First and Second Excited States of R6G Dye with the Fabry–Perot Cavity

Coupling of macroscopic ensembles of highly concentrated R6G molecules with aluminum and silver Fabry–Perot cavities of different sizes, in which one or two standing wave modes are in resonance with the absorption transition(s) of the dye molecules, have been studied. (i) It has been found that strong coupling of the cavity with one molecular eigenstate (S0→S1 transition) does not perturb the energies of the other molecular states. (ii) The S0→S2 absorption transition is too weak to strongly couple to the resonant cavity (“λ” standing wave mode). However, the resonant cavity causes a blue shift of the S0→S2 excitation band. (iii) The splitting of the dispersion curve is theoretically predicted and experimentally observed at strong coupling of the cavity resonance (“λ” standing wave mode) with the material resonances of Ag, including bound electron and “epsilon equal zero” transitions.

Photoluminescent Property of Electrochemically Self-Assembled CuSCN/Dye Hybrid Thin Films

Nanostructured hybrid thin films of crystalline CuSCN and fluorescent cationic dyes; Rhodamine B (RB), Nile Blue A (NB) and 4-(N,N-dimethylamino)-4’-(N’-methyl)stilbazolium (DAS) were obtained by electrochemical self-assembly from a single pot containing all the chemical ingredients. Concerted functionalities achieved by the intimate interaction between CuSCN and dye was studied for photoluminescence (PL) behavior between 77 and 298 K. PL from RB and NB was totally quenched when they were hybridized with CuSCN, due to hole transfer from the dye excited state to the valence band of CuSCN, potentially indicating their use as light absorber in solar cells and photodiodes. On the contrary, that of DAS was not quenched despite of its favorable HOMO position for the hole transfer. Crystalline DAS salt with tosylate (DAST) exhibited a strong exciton-phonon coupling to weaken, broaden and red-shift PL at room temperature, so that it inversely is strongly enhanced, sharpened and blue-shifted at 77 K. The PL of the same chromophore in the hybrid thin film, however, shows a slight red-shift and only moderate enhancement at reduced temperature, due to exciton stabilization and energy transfer from CuSCN to DAS luminophore, making it a unique nearly temperature-independent luminescent material.

Tetrathiafulvalene Scaffold-Based Sensitizer on Hierarchical Porous TiO2: Efficient Light-Harvesting Material for Hydrogen Production

In this work, a photochemical device that contains thioalkyl-substituted tetrathiafulvalene dyes and hierarchical porous TiO2 has been designed and successfully employed in visible light-driven hydrogen production. The design strategy boosts up the desirable photophysical properties of catalysts and is well supported by optical, electrochemical, and computational studies. The introduction of thioalkyl-substituted tetrathiafulvalene dyes as light-harvesting sensitizers onto the porous TiO2 triggers unprecedented high rate of hydrogen evolution. This study focuses on the role of thiafulvalene scaffold, which can promote ultrafast interfacial electron injection from excited-state dye into the hierarchical porous TiO2 conduction band. The purposeful construction of this integrated composite G3T3 (dye content 1.0 μmol in 10 mg Pt-TiO2 composite) significantly increases the hydrogen production rate of 24 560 μmol h–1 gcat–1 with high apparent quantum yield ∼41%. In the study, the absorption onset of both sensit...

The role of lithium cations on the photochemistry of ruthenium complexes in dye-sensitized solar cells: A TDDFT study with the BCL model

Lithium cations have been shown to impart an electrostatic Stark effect on molecules bound to mesoporous metal oxides commonly used in dye-sensitized solar cells. Herein, using the Barrera-Crivelli-Loeb theoretical model accompanied by Time Dependent Density Functional Theory calculations, we examined the influence that lithium cations have on the performance of dye-sensitized solar cells that incorporate [Ru(dmb)2(dcbH)]2+ sensitizers, where dmb is 4,4′-dimethyl-2,2′-bipyridine and dcbH is 4,4′-dicarboxylic acid-2,2′-bipyridine was examined. Simulations suggest that an enhanced photocurrent occurs in the presence of lithium cations, which is attributed to the photochemical generation of an excited-state dye–lithium adduct. In this adduct, a lithium cation is interacting with the carbonyl moieties of the dcbH ligands, which results in a bathochromic shift of the [Ru(dmb)2(dcbH)]2+ metal-to-ligand charge-transfer spectral band. This shift in absorption can be canceled by introducing a hypothetical dipolar electric field of 7.3 MV/cm, in good agreement with experimentally reported values for Stark effects observed under solar excitation of TiO2 functionalized with these types of sensitizer molecules. This indicates that lithium cations not only interact with the metal-oxide semiconductor, as shown previously, but also interact directly with the dye upon photoexcitation, something that should be considered when designing and evaluating new sensitizers.

Features of deactivation of excited states of cationic polymethine dye in the matrices of halogen-containing derivatives of poly-N-epoxypropyl carbazole

Singlet and triplet states of the cationic polymethine dye in polymers that are derivatives of poly-N-epoxypropyl carbazole with heavy atoms of different chemical nature were studied. It was shown that the presence of heavy atoms in the structure of the polymer leads to an appearance and rise of the dye phosphorescence due to the growth of the spin-orbit interaction in the dye molecule and increasing in the rate of singlet-triplet transitions. Also, the appearance of recombination luminescence indicated the formation and recombination of electron-hole pairs, which is an additional channel of relaxation of excited states of the dye in hole conducting polymer films. It was shown that external magnetic field leads to decreasing in the intensity of recombination luminescence. The time-dependent behavior of the magnetic effect is the result of competition between the singlet and triplet channels of the formation of the electron-hole pairs.

Light harvesting and charge management by Ni4S3 modified metal−organic frameworks and rGO in the process of photocatalysis

Harvesting and charge management is obtained by means of Ni4S3 modified Metal−organic Frameworks (MOF) and rGO, namely, the Uio-66 (Zr)/rGO combined with Ni4S3 photocatalyst was successfully prepared with the solvothermal method. The Ni4S3 acted as the electron transfer agent greatly improve the electrons transmission from the excited state dye to the rGO/MOF surface for proton reduction reaction. The hydrogen production amount over EY-sensitized rGO/MOF/Ni4S3 photocatalyst has reached 280 μmol for 5 h, which is about 14 times than that of the pure Ni4S3 photocatalyst and 185 times than that of the pure rGO/MOF photocatalyst under visible light irradiation (λ ≥ 420 nm). In the composite, the rGO acts as electron-transfer mediator and Ni4S3 serves as H2-evolution active site. A series of studies shown that the Ni4S3 modified MOF and rGO provided more active sites and improved the efficiency of photo-generated charge separation by means of several characterizations such as SEM, XRD, XPS, Element Mapping, UV–vis DRS, BET, Photocurrent, Voltammetric Scanning, Fluorescence Spectra and FTIR. and the results of which were in good agreement with each other. The photoelectron migration rate and photogenerated charge separation efficiency of the composite can be obviously increased with graphene as a good electron acceptor and transfer medium and Ni4S3 as hydrogen producing active site.

Design of novel phenanthrocarbazole dyes for efficient applications in dye-sensitized solar cells

Phenanthrocarbazole (PC)-based organic dye-sensitized solar cells (DSSCs) have been recently reported in experiments with an impressive high power conversion efficiency of over 12%. In this paper we report a computational study of the electronic structures, optical parameters and electron injection properties of a series of five PC dyes and the dye-TiO2 interfaces. Density functional theory (DFT) and time-dependent DFT (TDDFT) approaches were employed. We show that the incorporation of additional building blocks (indoline, carbazole, triphenylamine, or coumarin) to the PC donor moiety leads to obvious influence on the electronic structures and properties, compared to unitary electron donor PC dye. The binary electron-donor PC based dyes demonstrate better electronic properties and spectroscopic parameters. The calculated injection time of electrons from the excited state of dye to the conduction band of TiO2 is ideal for DSSC applications. The newly designed coumarin-PC and indoline-PC dyes show desirable energetic, electronic, and spectroscopic parameters for DSSCs. Our results are useful for a better understanding on the design rule of PC based organic dyes for future DSSCs.

Comparison of Complexation-Induced pKa Shifts in the Ground and Excited States of Dyes as Well as Different Macrocyclic Hosts and Their Manifestation in Host-Retarded Excited-Dye Deprotonation.

1-Aminopyrene and 1-naphthylamine-5-sulfonic acid were converted to the putrescine (1,4-diaminobutane)-substituted derivatives (dyes 1 and 2). The diaminobutyl anchor serves as a common binding motive for cation-receptor macrocycles such as cucurbit[n]urils (n = 6-8) and p-sulfonatocalix[4]arene. When protonated, they are prone to undergo a rapid deprotonation in their excited state to result in fluorescence from the unprotonated form (Förster cycle). The deprotonation can be suppressed by complexation with cation-receptor macrocycles, which allows the fluorescence of the locally excited (protonated) state to be dramatically enhanced (factor 12 for dye 1 and 83 for dye 2). This host-retarded excited-dye deprotonation is a direct consequence of the previously established complexation-induced pKa shifts that dyes undergo upon binding to a macrocyclic host. The data set also allows a systematic comparison of complexation-induced pKa shifts in the ground and excited state of a dye. The trends are comparable, which suggests that structural factors, that is, the geometry of the host-guest complexes, determine the magnitude of the shifts. In regard to the magnitude of the absolute pKa shifts on the size of the macrocycles, we observe for dye 2 that the complexation-induced pKa shifts decrease as the portals become larger along the cucurbit[n]uril series.

Phototransformation of cyanine dye with two chromophores. Effects of oxygen and dye concentration

Abstract Phototransformation of a cyanine dye with two chromophores (biscyanine dye, BCD) subject to visible light in phosphate buffer was studied using optical absorption and fluorescence spectroscopic techniques. The effects of the dye concentration and molecular oxygen were demonstrated. The monoexponencial dependence of optical absorption of the BCD solution on the irradiation time was observed. The increase of the characteristic phototransformation time with the dye concentration is explained in terms of the dye aggregation. The explanation is confirmed by experiments in the presence of SDS micelles, where the concentration effect is absent, since at binding with SDS micelles BCD does not aggregate. The dye phototransformation rate increase in the presence of oxygen is explained in terms of singlet oxygen formation due to energy transfer from the dye excited triplet state to molecular oxygen. Singlet oxygen was detected, and its quantum yield was determined by an indirect chemical method. The effect of singlet oxygen on the BCD phototransformation was confirmed by reduction of its phototransformation rate in the presence of 2,5-dimethylfuran, a known singlet oxygen water soluble quencher. Singlet oxygen may destroy the π-conjugation of the BCD chromophores. A possible structure of the dye photoproduct is proposed based on the similarity of its spectral characteristics and those of monochromophoric cyanine dye and confirmed by quantum chemical modelling.

Enabling Efficient Creation of Long-Lived Charge-Separation on Dye-Sensitized NiO Photocathodes.

The hole-injection and recombination photophysics for NiO sensitized with RuP ([RuII(bpy)2(4,4'-(PO3H2)2-bpy)]2+) are explored. Ultrafast transient absorption (TA) measurements performed with an external electrochemical bias reveal the efficiency for productive hole-injection, that is, quenching of the dye excited state that results in a detectable charge-separated electron-hole pair, is linearly dependent on the electronic occupation of intragap states in the NiO film. Population of these states via a negative applied potential increases the efficiency from 0% to 100%. The results indicate the primary loss mechanism for dye-sensitized NiO is rapid nongeminate recombination enabled by the presence of latent holes in the surface of the NiO film. Our findings suggest a new design paradigm for NiO photocathodes and devices centered on the avoidance of this recombination pathway.

Calculation of DSSC parameters based on ZnO nanorod/TiO2 mesoporous photoanode

Photoanode of dye sensitized solar cell (DSSC) plays an important role as electron transport media to accept photogenerated electron from excited state of dye. There are several physical properties that are required from photoanode of DSSC. It should be highly transparent, have large surface area, has a conduction band lower than LUMO of dye molecule, has high charge carrier mobility and finally has a good stability in redox electrolyte process. In this work, DSSC with structure FTO/ZnO nanorod/TiO2 mesoporous/Ru-dye/gel electrolyte/ Pt/FTO has been fabricated. In order to modified the structures of photoanode, ZnO nanorod was grown on aluminium doped ZnO seed layer by variation concentration of Al (0 wt%, 0.5 wt% and 1.0 wt%). Zinc nitrate hexahydrate and hexamethylenetetramine used as raw materials for ZnO nanorod growth solution and deposited by self-assembly methods on FTO/Al doped ZnO seed layer. It is then followed by deposition of titania (TiO2) paste by screen printing methods. DSSC parameters i.e. ideally factor (n), series resistance (RS), and shunt resistance (RSH) was derived from current density-voltage (I-V) curve using the simplify equation of ideal diode model. The influences of ZnO photoanode structures to the solar cell performance will be completely discussed.