Ezequiel Paz Totolhua

Dr. Ezequiel Paz Totolhua

Posgrado en Dispositivos Semiconductores, Benemérita Universidad Autonoma de Puebla, Puebla, Mexico
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Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 April 2025 in Materials
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Journal Article
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Ezequiel Paz TotolhuaEzequiel Paz Totolhua
Ezequiel Paz Totolhua
JLJesús Carrillo López
Jesús Carrillo López
JLJ.A. David Hernández-de la Luz
J.A. David Hernández-de la Luz
KMKarim Monfil-Leyva
Karim Monfil-Leyva
Javier Flores MéndezJavier Flores Méndez
Javier Flores Méndez
JLJosé Alberto Luna López
José Alberto Luna López
Mixed-halide perovskites enable the creation of high-performance and low-cost solar cells. Chloride incorporation enhances film morphology, carrier diffusion length, and stability, improving device performance. Nevertheless, optimizing film thickness, defect density, and metal contact work function remains insufficiently explored, despite its potential to enhance power conversion efficiency. In this study, a numerical simulation was performed using SCAPS-1D (version 3.3.10) to identify the optimal parameters for the FTO/TiO2/CH3NH3Pb3−xClx/Spiro-OMeTAD/Au configuration. The best performance parameters that have been published in the literature based on experimental results are as follows: VOC = 1.077 V, JSC = 21.45 mA/cm2, FF = 77.57%, and PCE = 17.97%. In contrast, the performance parameters obtained from numerical simulations for the same structure are VOC = 1.28 V, JSC = 21.63 mA/cm2, FF = 78%, and PCE = 21.53%. In our numerical analysis, we achieved efficiencies that were comparable to those reported in experimental studies, and after optimization, superior performance parameters were attained, including VOC = 1.179 V, JSC = 27.26 mA/cm2, FF = 81.03%, and PCE = 26.07%. These results indicate that optimized parameters can be integrated into the design and fabrication of mixed-halide perovskite solar cells to enhance performance.

30 November 2023 in Materials
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Journal Article
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Ezequiel Paz TotolhuaEzequiel Paz Totolhua
Ezequiel Paz Totolhua
JLJesús Carrillo López
Jesús Carrillo López
ALAlfredo Benítez Lara
Alfredo Benítez Lara
KMKarim Monfil-Leyva
Karim Monfil-Leyva
ARA.C. Piñón Reyes
A.C. Piñón Reyes
JLJosé Alberto Luna López
José Alberto Luna López
Inverted perovskite solar cells (PSCs) have gained much attention due to their low hysteresis effect, easy fabrication, and good stability. In this research, an inverted perovskite solar cell ITO/PEDOT:PSS/CH3NH3PbI3/PCBM/Ag structure was simulated and optimized using SCAPS-1D version 3.3.10 software. The influence on the device of parameters, including perovskite thickness, total defect density, series and shunt resistances, and operating temperature, are discussed and analyzed. With optimized parameters, the efficiency increased from 13.47% to 18.33%. Then, a new SiOx/ITO/PEDOT:PSS/CH3NH3PbI3/PCBM/Ag device was proposed which includes a silicon-rich oxide (SiOx) layer. This material was used as the down-conversion energy material, which converts high-energy photons (ultraviolet UV light) into low-energy photons (visible light), improving the stability and absorption of the device. Finally, with SiOx, we obtained an efficiency of 22.46% in the simulation. Therefore, the device with the SiOx layer is the most suitable as it has better values for current density–voltage output and quantum efficiency than the device without SiOx.

28 April 2026 in Processes
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Journal Article
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Ezequiel Paz TotolhuaEzequiel Paz Totolhua
Ezequiel Paz Totolhua
Mario MorenoMario Moreno
Mario Moreno
Javier Flores MéndezJavier Flores Méndez
Javier Flores Méndez
AMAlfredo Morales
Alfredo Morales
ARA.C. Piñón Reyes
A.C. Piñón Reyes
JLJosé Alberto Luna López
José Alberto Luna López
This research study conducts a computational analysis of a two-terminal (2T) Perovskite-on-silicon (PVK-Si) solar cell with a tandem configuration. The motivation for this analysis arises from the outstanding potential of PVK-Si solar cells to surpass the efficiency limitations of conventional photovoltaic technology. The tandem configuration utilizes a combination of CsSnBr3 in the top sub-cell and crystalline silicon (c-Si) in the bottom sub-cell. After optimizing parameters of the top sub-cell (FTO/TiO2/CsSnBr3/rGO/Au), which included the thicknesses of CsSnBr3 (500 nm), TiO2 (40 nm), rGO (50 nm), the interface defects (1013 cm−2), and the bandgap of CsSnBr3 (1.78 eV), the PVK-Si tandem device was simulated. As a result, the top CsSnBr3 sub-cell achieved an efficiency of 21.62%, while the bottom silicon sub-cell achieved an efficiency of 23.48%. Subsequently, the sub-cells were interconnected in series using filtered spectra and current-density matching. After interpolating the J-V curves, the tandem exhibited a global efficiency of 29.76%, a fill factor (FF) of 85.30%, a matched current density (JSC) of 19.02 mA/cm2, and an open-circuit voltage (VOC) of 1.83 V. The EQE results confirmed efficient photon management via complementary sub-cell absorption. The performance is competitive with experimental lead-based tandems and exceeds that of current lead-free simulations. Therefore, this research proposes a viable pathway for the development of non-toxic, cost-effective tandem solar systems with manufacturing capabilities.

30 June 2023 in Revista de Energías Renovables
Verified
Journal Article
Open access
Ezequiel Paz TotolhuaEzequiel Paz Totolhua
Ezequiel Paz Totolhua
In this research work, an inverted p-i-n type perovskite solar cell: ITO/PEDOT: PSS/CH3NH3PbI3/PCBM/Au has been simulated and optimized in SCAPS-1D. The optimized parameters in SCAPS-1D that improved solar performance were: perovskite thickness, the total defect density of perovskite, the total defect density of interfaces, series and shunt resistances, and device operating temperature. As a result, the efficiency (PCE) increased to 18.33%. Subsequently, when the silicon-rich oxide (SiOx) material was implemented in the simulation as downconversion energy material on the outside of the cell, a power conversion efficiency (PCE) of 23.7% was obtained. The SiOX film obtained experimentally by sputtering obtained good photoluminescence, absorption coefficient, band gap, and transmittance characteristics before and after thermal annealing. These characteristics have been considered for the proposed device. It is indicated that the inverted perovskite solar cell of type pi-n: SiOx/ITO/PEDOT:PSS/CH3NH3PbI3/PCBM/Au has better J-V output values and EQ quantum efficiency than the perovskite solar cell without SiOx.