183 

This work is licensed under a Creative Commons Attribution 4.0 International License 

 IHJPAS. 37 (2) 2024 

Ibn Al-Haitham Journal for Pure and Applied Sciences 

Journal homepage: jih.uobaghdad.edu.iq 

PISSN: 1609-4042, EISSN: 2521-3407 

 

  

 

 

Hadi J.M. Al-Agealy1* , Hossain Milani Moghaddam2  and Mudhafar J. Ali3  

1Department of physics ,College of Education for Pure Science (Ibn-AL Haitham), University of Baghdad,   

           Baghdad, Iraq. 
 2,3Department of Solid-State Physics, Faculty of Basic Sciences, University of Mazandaran,  Babolsar, Iran. 

*Corresponding Author.  

 Received: 5 April 2023                                Accepted: 8 May 2023                          Published: 20 April 2024 

Abstract                

Abstract  

   A theoretical study of electronic characteristics based on charge transfer using quantum model 

N719 dye-sensitized contact with TiO2 in solar cells. The current density expression used to calculate 

the photovoltaic characteristics is assumed to be a continuum level of the N719 dye and TiO2 

semiconductor in the heterojunction N719-TiO2 devices using the MATLAB program. The transition 

energy, current, fill factor, and efficiency of N719-TiO2 DSSCs are calculated based on quantum 

transition theory. The performance of DSSCs photovoltaic was estimated based on the I-V 

characteristics of the N719-TiO2 device using concentrations (7 × 1018 𝑐𝑚−3) at (100 mW/cm2) 

irradiation. The N719-TiO2 device with Butanol solvent at concentration (3 × 1018𝑐𝑚−3) shows 

0.8299 V, and (37.3034 mA/cm2) of open-circuit voltage and short-circuit current respectively fill 

factor of 0.206 compared to the open circuit of 0.8398 V and (87.5728 mA/cm2) and short-circuit 

current with fill factor of 0.257 at concentration of carrier (7 × 1018𝑐𝑚−3). Current density and fill 

factor at limited transition energy increase with increasing the coupling constant and concentration 

of   N719 - TiO2 hetero junction and vice versa. 

Keywords: Electronic Characteristic, TiO 2 -N719, Dye-Sensitized, Solar Cell. 

 

 1. Introduction 

 Concerns around climate change as a result of rising carbon dioxide levels in the atmosphere using 

fossil fuels and the increased demand for electricity due to an ever-growing population necessitate an 

effort to move away from the classical methods of energy production [1]. The necessity of switching 

to renewable energy to produce energy is urgent today. We can harness alternative sources for 

providing a sustainable and clean future using sunlight energy. Within this context, it is accessible, 

eco-friendly, and universal [2]. The photovoltaic solar cell has become more interested in energy 

research because it is a promised solution to the efficient conversion of solar energy. Additionally, 

more performance and device advancements are required to use this technology successfully in life 

[3]. The solar energy is one of the most sustainable and inexhaustible renewable sources that converts 

sunlight directly into electricity using solar cell devices without any  pollutants [4]. Dye-sensitized 

solar cells, or "DSSCs," were begun after the work of Brian O’Regan and Michael Grätzel and have 

become a topic of interesting research for solar energy conversion because of their ease of 

doi.org/10.30526/37.2.3381 

Theoretical Study of the Electronic Characteristic of a TiO2 -N719 

Dye-Sensitized Solar Cell 

 

https://creativecommons.org/licenses/by/4.0/
https://jih.uobaghdad.edu.iq/index.php/j/index#1609-4042
https://jih.uobaghdad.edu.iq/index.php/j/index#2521-3407
https://orcid.org/0000-0002-6876-7692
mailto:hadi.j.m@ihcoedu.uobaghdad.edu.iq
https://orcid.org/
mailto:milani@umz.ac.ir
https://orcid.org/
mailto:mudhafar-jebur@outlook.com


IHJPAS. 37 (2) 2024 

184 
 

manufacture, low costs, eco-friendliness, and high conversion efficiency [5]. The dye-sensitized solar 

cells (DSSCs) are third-generation photo-electrochemical cells, and the photoactive electrodes are 

metal oxide and liquid-state electrolytes. In the last decade, DSSC has attracted considerably more 

interest because of its low-cost production, ease of process, and high photoelectrochemical 

performance [6]. 

TiO2 is one of the oxide semiconductors with broadband gaps used as dye-adsorbed in the DSSCs 

technology that's renewed by the redox-coupled electrolyte solution [7]. The active medium usually 

consists of a donor state (organic solar cell) and an acceptor state (semiconductor) [8]. The basic 

reaction process in molecule contact with semiconductor electronic devices is the charge transfer 

reaction; electrons are moving between the donor state and the acceptor state [9]. The charge transfer 

is the main process in DSSCs that occurs in the solar cell system. Therefore, the transfer occurs under 

the assumed alignment of the energy levels of both the donor and acceptor states in DSSCs devices 

[10]. The N719 sensitized dye is widely used in DSSCs solar cells according to its many best 

characteristics, such as optical, electrochemical, synthesis, and photovoltaic properties [11]. In recent 

decades, charge transfer theory has been developed using different tools: analytical theory methods, 

time resolution, spectroscopy, and computer simulation [12]. 

 Hadi et al. studied the charge transfer process in heterostructure devices according to the orientation 

energy under the alignment of energy states for materials in electronic devices. Electrons' move from 

one state to another is required to close energy levels in both materials [13]. The charge transfer in 

heterostructure devices depends on the orientation of the energy state in both the donor and acceptor 

states of contact [14]. DSSCs contain a sensitizer dye that absorbs sunlight to excite, and electrons 

are moved into the conduction band of TiO2. In general, the ruthenium N719 sensitizer dye has the 

best electronic stability and transportability to be used in DSSCs [15]. More TiO2 is being used as a 

photoanode for DSSC because it has a large surface area, is chemically stable, has large catalyst band 

edges, is not toxic, and has low recombination [16]. In recent years, the development of device 

structures, redox mediators, and sensitizers has improved the performance of DSSCs [17]. 

 Di-tetrabutylammonium, cis-bis (isothiocyanato) bis (2,2′-bipyridyl-dicarboxylato 4,4′) N719-

Rhenium(II) sensitizers are one of the appropriate sensitizer molecules with DSSCs [18]. Figure 1, 

illustrates the chemical structure of N719 [19]. In this work, the electronic characteristics of the N719-

TiO2 heterojunction have been studied theoretically based on transition theory according to the 

quantum model. 

 

 
Figure 1. Structure of N719 sensitised dye [19] 

 

 

2. Theory     
The probability of charge transfer per unit time from one state to another state in hetro- junction 



IHJPAS. 37 (2) 2024 

185 
 

may be given as [20]. 

𝑇𝐷
𝐴(𝐸) = ∑

4𝜋2

ℎ
|〈𝐻𝐶〉|2 𝜌𝑎𝑐(𝐸)                                                                                                          (1) 

Where ℎ is Planck constant, 𝐻𝐶 is the coupling constant between materials in hetro junction and 

𝜌𝑎𝑐(𝐸) is activation density, 𝜌𝑎𝑐(𝐸) is given by [21].  

𝜌𝑎𝑐(𝐸) = 𝐷𝑆
𝑙𝑎𝑐

 (
6

𝜋
)

1
3⁄
                                                                                                                             (2) 

where 𝐷𝑆 the density of states at room temperature is, 𝑙𝑎𝑐 is the activated length .The density of states 

for 

 the charge transfer can be written as [22] 

𝐷𝑆 = 𝐷𝑑(𝐸)〈�̂�〉𝑑𝑆

−2
3⁄

                                                                                                                         (3) 

where 𝐷𝑑(𝐸) is density of charge in dye, 〈�̂�〉 is the density of state in a system, 𝑑𝑠 is the atomic 

density in semiconductor. The density of state in a system 〈�̂�〉  is [23].  

〈�̂�〉 =
1

√4𝜋Λ𝑆
𝑀𝑘𝐵𝑇

𝑒− (Λ𝑆
𝑀+∆𝐹0)2                         

4Λ𝑆
𝑀𝑘𝐵𝑇

                                                                                            (4)  

where ∆𝐹0 is driving energy, 𝑘𝐵 is Boltzman constant ,T is room temperature, and Λ𝑆
𝑀 is the transition 

energy .The driving energy ∆𝐹0 is given by[24]. 

∆𝐹0 = (𝐸𝑐𝑞𝐸𝑜)                                                                                                                                 (5) 

where 𝐸𝑐 is conduction band of TiO2 and 𝑞𝐸𝑜 is chemical potential of dye . Inserting Eqs (4),(3) 

and (2)  in Eqs (1) to obtain . 

𝑇𝐷
𝐴(𝐸) = ∑

4𝜋2

ℎ
|〈𝐻𝐶〉|2 𝐷𝑑(𝐸)

1

√4𝜋Λ𝑆
𝑀𝑘𝐵𝑇

𝑒− (Λ𝑆
𝑀+∆𝐹0)2

4Λ𝑆
𝑀𝑘𝐵𝑇

𝑑𝑆

−2
3⁄ 𝑙𝑎𝑐

 (
6

𝜋
)

1
3⁄
.                                                 (6) 

The current of charge through system is [25]. 

𝐼 = 𝑒 ∑ 𝐹(𝐸)𝑇𝐷
𝐴(𝐸)                                                                                                                                       (7) 

where 𝐹(𝐸) is Fermi distribution in system. Inserting Eq.(6) in Eq.(7) and integrate to result.  

𝐼 =
4𝜋2

ℎ
|〈𝐻𝐶〉|2 1

√4𝜋Λ𝑆
𝑀𝑘𝐵𝑇

𝑒
−

(Λ+∆𝐹0)2

4Λ𝑘𝐵𝑇 𝑑𝑆

−2
3⁄ 𝑙𝑎𝑐

 (
6

𝜋
)

1
3⁄

∫ 𝐷𝑑(𝐸)𝐹(𝐸)𝑑𝐸
𝑞𝐸

0
                                                (8) 

Integral in Equations 8 over chemical potential of dye is reduced to concentration of dye [𝑛] [26] 

∫ 𝐷𝑑(𝐸)𝐹(𝐸)𝑑𝐸
𝑞𝐸

0
= [𝑛]                                                                                                                 (9) 

 

 The current expression in Eq.(8) with Eq.(8) is reduced to: 

  𝐼(𝑚𝐴) =
4𝜋2

ℎ
[𝑛]|〈𝐻𝐶〉|2 1

√4𝜋Λ𝑆
𝑀𝑘𝐵𝑇

𝑒
−

(Λ+∆𝐹0)
2

4Λ𝑘𝐵𝑇 𝑑𝑆

−2
3⁄ 𝑙𝑎𝑐

 (
6

𝜋
)

1
3⁄
                                                           (10)              

The atomic density of semiconductor  𝑑𝑠 is estimated using the number of states 𝑁𝑠 and density of 

states  𝐷𝑠  and is written as [27].  

 𝑑𝑠 =
𝑁𝑠

𝐷𝑠
                                                                                                                                                (11)                                  



IHJPAS. 37 (2) 2024 

186 
 

The density of states  𝐷𝑠 of semiconductor is estimated using formula [27]. 

 𝐷𝑠 =
3

2
(

𝑁𝑒

𝐸𝐹
)                                                                                                                                  (12) 

where 𝑁𝑒 is carrier concentration and 𝐸𝐹 is Fermi energy of semiconductor. The current density is 

given by ratio of current divided on area and given by  

𝐼 (
𝑚𝐴

𝐶𝑚2) =
 𝐼(𝑚𝐴)

𝐴𝑟𝑒𝑎
                                                                                                                                               (13) 

The fill factor is ratio relative to I-V curve's maximum power is unit less, it describes to the maximum 

power 𝐽𝑚𝑉𝑚. and give ratio [28].  

𝐹𝐹 =
𝐽𝑚𝑉𝑚

𝐽𝑆𝑐𝑉𝑜𝑐
                                                                                                                                                    (14) 

where 𝐼𝑆𝑐   is short-circuit current, and Voc is open circuit voltages. Transition energy for charge 

transfer from one state to another state is [29]. 

 Λ𝐴𝐷(𝑒𝑉) =
𝑒2

8𝜋𝜀°
 [

1

𝐷
Λ(𝑛, 𝜀) −

1

2𝑅
[Λ(𝑛𝑆𝑒𝑚, 𝑛) − Λ(𝜀𝑆𝑒𝑚, 𝜀)]]                                                         (15)      

Where 𝑒 and 𝜀° are electric charge and vacuum permittivity, 𝐷 and R are the radius  dye and distance 

between the complex and the semiconductor, respectively, Λ(𝑛, 𝜖) = [
1

𝑛2 −
1

𝜀
] is the polarity solvent 

as function of refrective index 𝑛 and dielectric constant 𝜀 of solvent, Λ(𝑛𝑆𝑒𝑚, 𝑛) = [(
𝑛𝑆𝑒𝑚

2 −𝑛2

𝑛𝑆𝑒𝑚
2 +𝑛2)( 

1

𝑛2)] 

is an optical dielectric for semiconductor - solvent term where 𝑛𝑆𝑒𝑚 is refrective index of 

semiconductor and Λ (𝜀𝑆𝑒𝑚, 𝜀) = [
𝜀𝑆𝑒𝑚

2 −𝜀2

𝜀𝑆𝑒𝑚
2 +𝜀2  

1

𝜀2] is statical dielectric term where 𝜀𝑆𝑒𝑚 is dielectric 

constant of the semiconductor. The radii of atom and molecule evaluate according to apparent molar 

volumes approach [30]. 

𝐷(𝑚) = (
3

4𝜋
 

𝑀

𝑁𝜌
)

1

3                                                                                                                                            (16) 

where M is the m 

olecular weight, N is the Avogadro number, and ρ is the density of material. 

 

3.  Results and discussion 

 The electronic characteristic of TiO 2-N719 hetero junction is investigated based on a theoretical 

model for charge transfer in DSSCs solar cell. We estimate the transition energy, current, atomic 

density, density of states, current density, and fill factor according to a simple theoretical scenario. In 

general, the electronic characteristics of N719-TiO2 devices were calculated theoretically by a 

MATLAB program as a function of transition energy Λ𝑆
𝑀(𝑒𝑉 in Eq. (15). Firstly, we calculate the 

radii of N719 and TiO2 according to the continuum model. In essence, the radii of both N719 dye  

and TiO2 are estimated using Eq.(16) by taking the molecular weight and density, M= 1188.55g/mol; 

the density 𝜌 = 1.52 
g

 𝑐𝑚3  for N719 dye and M=79.866g/mol and  𝜌 = 4.23
g

 𝑐𝑚3for TiO2[31], results 

of the radii of N719 and TiO2 are 6.769 𝐴° and 1.956 𝐴0, respectively. Transition energy is calculated 

using Eq. (16) by inserting the parameters n=1.3993 and 𝜀 = 17.51 of 1-Butanol [32], 𝑛𝑆 = 2.609 

[31] and 𝜀𝑆 = 55 for TiO2, 𝐷 = 6.769 𝐴°, R=8.725 𝐴°to result Λ𝑆
𝑀 = 0.367eV. It shows that the 

N719-TiO2 system needs 0.367eV to start transferring from excited levels of dye to the conduction 

band in the TiO2 semiconductor. The density of states of the  𝐷𝑠 of TiO2 semiconductor is calculated 

by inserting the carrier concentration  𝑁𝑒 = 1.4 × 1014 1

𝐶𝑚3
 [33] and Fermi energy 𝐸𝐹 = 4.19𝑒𝑉 [34] 



IHJPAS. 37 (2) 2024 

187 
 

in Eq. (12) to give 𝐷𝑠 = 3.34 × 1013 electron

cm3.eV
 . The atomic density in Eq. (11) was estimated using 

𝑁𝑠 = 8
𝑒𝑙𝑒𝑐𝑡𝑟𝑜𝑛

𝑒𝑉
 and  𝐷𝑠 = 3.34 × 1013 electron

cm3.eV
 [32] to result 𝑑𝑠 = 4.1766 × 1018 1

𝑚3 
. The electronic 

current of N719-TiO2 solar cell with 1-Butanol solvent is calculated using Eq.(10) which takes 

|〈𝐻𝐶〉|2=0.15,0.25,0.35,0.45,0.55,0.65,0.75,0.85, 0.95,1.05,1.15,1.25,1.35,1.45and 

1.55 × 10−2𝑒𝑉2,Λ𝑆
𝑀 = 0.339 𝑒𝑉, 𝑙𝑎𝑐 = 3𝐴0, 𝑑𝑠 = 4.17 × 1018 1

𝑚3 
 , [𝑛] = (3 and7) × 1024 1

m3 
 

[35], results are listed in Table 1. 

 

Table 1. Results of electronic current calculation for N749/TiO2with 1-Butanol solvent 

 

Strength coupling  |𝐞𝐕/ 𝐬𝐭𝐚𝐭𝐞|𝟐 

 |〈𝑪𝑪𝑬𝑻〉|𝟐x10−2   

The electronic current 

The electronic concentration 

𝟑 × 𝟏𝟎𝟐𝟒  
𝟏

𝒎𝟑 
 𝟕 × 𝟏𝟎𝟐𝟒  

𝟏

𝒎𝟑 
  

0.15 1.6666E-03 3.8888E-03 

0.25 2.7777E-03 6.4814E-03 

0.35 3.8888E-03 9.0739E-03 

0.45 4.9999E-03 1.1666E-02 

0.55 6.1110E-03 1.4259E-02 

0.65 7.2221E-03 1.6852E-02 

0.75 8.3332E-03 1.9444E-02 

0.85 9.4443E-03 2.2037E-02 

0.95 1.0555E-02 2.4629E-02 

1.05 1.1666E-02 2.7222E-02 

1.15 1.2778E-02 2.9814E-02 

1.25 1.3889E-02 3.2407E-02 

1.35 1.5000E-02 3.4999E-02 

1.45 1.6111E-02 3.7592E-02 

1.55 1.7222E-02 4.0185E-02 

 

  The current in Table 1, indicates that it depends on the concentration and coupling constant between 

N719 dye and TiO2 in a solar cell system. It can be seen that the current is increased upon increasing 

the coupling between N719 and TiO2 and increasing the concentration. However, the current density 

is calculated according to Eq. (13) by taking the results from Table 1 and dividing by the area of the 

cell (0.49 𝑐𝑚2) [36]. The results are shown in Table 2.        

 

Table 2. Results of current density for N749/TiO2 with 1-Butanol 

 

Strength coupling  |𝐞𝐕/ 𝐬𝐭𝐚𝐭𝐞|𝟐 

 |〈𝑪𝑪𝑬𝑻〉|𝟐x10−2 

 

The   current density (
𝒎𝑨

𝑪𝒎𝟐) 

The electronic concentration 

𝟑 × 𝟏𝟎𝟏𝟖  
𝟏

𝑪𝒎𝟑 
 𝟕 × 𝟏𝟎𝟏𝟖  

𝟏

𝑪𝒎𝟑 
 

0.15 3.40122 7.9363 

0.25 5.6687 13.2273 

0.35 7.99363 18.51816 

0.45 10.2038 23.80816 

0.55 12.4714 29.1 

0.65 14.7387 34.3918 

0.75 17.0065 39.6816 

0.85 19.2747 44.97346 

0.95 21.54081 50.26326 

1.05 23,80816 55.5551 



IHJPAS. 37 (2) 2024 

188 
 

 

   

 

 

 

Both current and current density in Tables 1 and 2, are increased with increasing in the coupling of 

energy levels for dye and TiO2 in the system from 0.150x10−2  |eV/ state|2 to 1.550x10−2 

 |eV/ state|2. However, the current density in Table 2, increases with increasing the carrier 

concentration with 1-butanol solvent media in the system devices. In turn, the current density is 

affected by the fill factor and J-V characteristics of the cell. As it can be seen, the current density 

increases with an increasing the concentration from 3 × 1018 1

𝐶𝑚3 
  to 7 × 1018  

1

𝐶𝑚3 
 by a percentage 

2.33.  This means more electrons are transferred with increasing the carrier cross-interface of N719 

dye contact with the TiO2 hetero junction. Additionally, the concentration, coupling constant, and 

current density limit the electronic properties of N719-TiO2. The current density increases with 

increasing the coupling for concentrations in cell system. The photovoltaic J-V results of current 

density J (mA/cm2) and voltage in Volt for the N719 - TiO2 DSSCs using theoretical methods are 

shown in Table 3. 

Table 3. The photovoltaic J-V results for N719/TiO2 with 1-Butano  

The electronic concentration 

𝟑 × 𝟏𝟎𝟏𝟖
𝟏

𝒄𝒎𝟑
 𝟕 × 𝟏𝟎𝟏𝟖

𝟏

𝐜𝐦𝟑
 

V (volt) 
𝑱(𝑬)(

𝒎𝑨

𝒄𝒎𝟐
) 

V (volt) 
𝑱(𝑬)(

𝒎𝑨

𝒄𝒎𝟐
) 

0.8299 0 0.8398 0 

0.8 3.40122 0.8 7.9363 

0.75 5.6687 0.75 13.2273 

0.7 7.99363 0.7 18.51816 

0.65 10.2038 0.65 23.80816 

0.6 12.4714 0.6 29.1 

0.55 14.7387 0.55 34.3918 

0.5 17.0065 0.5 39.6816 

0.45 19.2747 0.45 44.97346 

0.4 21.54081 0.4 50.26326 

0.35 23,80816 0.35 55.5551 

0.3 26.07755 0.3 60.84489 

0.25 28.344898 0.25 136766. 

0.2 30.61224 0.2 71.4265 

0.15 32.87959 0.15 76.7183 

0.1 35.1469 0.1 82.201020 

0 37.3034 0 87.5728 

1.15 26.07755 60.84489 

1.25 28.344898 136766. 

1.35 30.61224 71.4265 

1.45 32.87959 76.7183 

1.55 35.1469 82.201020 



IHJPAS. 37 (2) 2024 

189 
 

The J-V characteristics are plotted in Figure 1, with two concentrations. Depending on the two 

curves in Figures 1 and 2 the average current and voltage in the open circuit can be limited, and the 

results are listed in Table 4 for both concentrations. Furthermore, the fill factor can be estimated 

using Eq.(14) under simulated AM 1.5 global sunlight (1 Sun, 100 mW/cm2) by using  data of 

average current and voltage in the open circuit from the curves in Figure 1. The results are shown 

in Table 4, for both concentrations of 1-butanol solvent. 

(A)                                                               (B) 

Figure 1. The J-V curves with concentration carrier A) 3 × 1018 1

𝑪𝒎𝟑  and B) 7 × 1018 1

𝑪𝒎𝟑  of the N719-TiO2 devices 

 

 

Table 4. Photovoltaic parameters of the N719-TiO2 DSSCs employing two different types of concentration carriers 

    

As it can be seen, the fill factor increases with increasing the concentration from  

3 × 1018 1/𝑐𝑚3to 7 × 1018 1/𝑐𝑚3. Table 4, shows that the average current 𝐽𝑚 is 32.755 mA/cm2 

and voltage 𝑉𝑚 is 0.195V in open-circuit where the current 𝐽𝑆𝑐 is 37.3034 mA/cm2 and the voltage 

𝑉𝑜𝑐 is 0.8299 V in open circuit. The fill factor FF = 0.206 of N719-TiO2 DSSC with concentration3 ×

1018𝑐𝑚−3. On the other hand, the average current 𝐽𝑚 is 61.010 mA/cm2 and the voltage 𝑉𝑚 is 0.31V 

in open-circuit where the current 𝐼𝑆𝑐 is 87.5728 mA/cm2 and voltage 𝑉𝑜𝑐 is 0.8398V in open circuit 

and that the cell achieved a FF = 0.257 at concentration 7 × 1018𝑐𝑚−3. However, 𝐽𝑆𝑐 ( 87.5728 

mAcm− 2) at concentration 7 × 1018𝑐𝑚−3 was relatively higher than 𝐽𝑆𝑐  ( 37.3034 mAcm− 2) at 

concentration 3 × 1018𝑐𝑚−3  and the 𝑉𝑜𝑐 (0.8398V) at 7 × 1018𝑐𝑚−3 was almost the same to the 

𝑉𝑜𝑐 ( 0.8299V) at concentration 3 × 1018𝑐𝑚−3 offered by the TiO2  electrode. However, the 

increased increasing the carrier concentration results in increasing the current density and fill factor.  

    

4.   Conclusion 

The electronic characteristics of the N719-TiO2 device are investigated and studied using a simple 

transition model for charge transfer using two different concentrations of carriers. The butanol solvent 

was an active media for the N719-TiO2 solar cell due to the transition energy that's affected by the 

Variables    The electronic concentration 𝟏/𝒄𝒎𝟑 

  

𝟑 × 𝟏𝟎𝟏𝟖 𝟕 × 𝟏𝟎𝟏𝟖 

𝑱𝑺𝒄(𝒎𝑨/𝒄𝒎𝟐)  37.3034  87.5728 

𝑽𝒐𝒄    Volt 0.8299 0.8398 

𝑱𝒎(𝒎𝑨/𝒄𝒎𝟐) 32.755 61.010 

𝑽𝒎    Volt 0.195 0.31 

F.F 0.206 0.257 



IHJPAS. 37 (2) 2024 

190 
 

current density and fills factor parameters. Current, current density, and fill factor are strongly 

influenced by concentration and coupling constants with limit transition energy. Increasing both 

coupling strength and concentration at limited transition energy reduced increased transfer through 

N719-TiO2 devices and affected the J-V characteristic and fill factor of the solar cell. The (61.010 

mA/ Cm2) and (0.31 Volt) exhibit large values of FF (0.286) at a carrier concentration of about 3 ×

1018 1

𝑐𝑚3, which helps in understanding the performance device. 

 

Acknowledgement  

    I extend my thanks to the College of Education for pure science Ibn Al-Haitham, University of 

Baghdad for assisting in completing this work by opening private laboratories and providing scientific 

facilities by the staff of the Physics Department to help support the research project. 

 

Conflict of Interest 

     The authors declare that they have no conflicts of interest. 

 

Funding: None. 

 

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