Search Results (77)

This paper presents the optimal sizing of a hybrid renewable energy system (HRES) for an isolated residential building using modified smell agent optimization (mSAO). The paper introduces a time-dependent approach that adapts the selection of the original SAO control parameters as the algorithm progresses through the optimization hyperspace. This modification addresses issues of poor convergence and suboptimal search in the original algorithm. Both the modified and standard algorithms were employed to design an HRES system comprising photovoltaic panels, wind turbines, fuel cells, batteries, and hydrogen storage, all connected via a DC-bus microgrid. The components were integrated with the microgrid using DC-DC power converters and supplied a designated load through a DC-AC inverter. Multiple operational scenarios and multi-objective criteria, including techno-economic metrics such as levelized cost of energy (LCOE) and loss of power supply probability (LPSP), were evaluated. Comparative analysis demonstrated that mSAO outperforms the standard SAO and the honey badger algorithm (HBA) used for the purpose of comparison only. Our simulation results highlighted that the PV–wind turbine–battery system achieved the best economic performance. In this case, the mSAO reduced the LPSP by approximately 38.89% and 87.50% over SAO and the HBA, respectively. Similarly, the mSAO also recorded LCOE performance superiority of 4.05% and 28.44% over SAO and the HBA, respectively. These results underscore the superiority of the mSAO in solving optimization problems. Full article

Recently, research and development in the field of dye-sensitized solar cells has been actively advanced, as the technology constitutes a potential alternative to silicon-based photovoltaic devices. Modification of the molecular structure of the dye can enhance the adsorption on the TiO₂ surface, improve the light absorption capacity, suppress the charge recombination, increase the electron injection rate, and thereby improve the overall performance of the solar cell. Carbazole and phenothiazine are rigid heterocyclic compounds containing nitrogen as a heteroatom with large π-conjugated skeletons. Phenothiazine differs from carbazole by the presence of sulfur as an additional electron-rich heteroatom. The inclusion of this heteroatom in the structure of the compounds can indeed improve the electron-donating properties, affect the conjugation, and thus affect the optical, electronic, and electrochemical properties of the chromophores as a whole. The difference in planarity when comparing carbazole with phenothiazine can be useful from several points of view. The planar structure of carbazole increases the degree of conjugation and the electron transfer capacity, which can increase the photocurrent of the cell. The nonplanar structure of phenothiazine helps to prevent π-stacking aggregation. This review comprehensively summarizes the progress in the field of synthesis of organic dyes for solar cells with an emphasis on the comparative analysis of two electron-donating moieties, carbazole and phenothiazine. In addition, the review describes in detail the relationship between the structure of the compounds (dyes), their properties, and the performance of solar cells. Full article

Despite the rapid efficiency advancement of perovskite solar cells (PSCs), non-radiative recombination at the buried interface between self-assembled monolayers (SAMs) and perovskite remains a critical bottleneck, primarily due to interfacial defects and energy level mismatch. In this study, we demonstrate a bifunctional interlayer engineering strategy by introducing 4,5-diiodoimidazole (4,5-Di-I) at the Me-4PACz/perovskite interface. This approach uniquely addresses two fundamental limitations of SAM-based interfaces: the insufficient defect passivation capability of conventional Me-4PACz due to steric hindrance effects and the poor perovskite wettability on hydrophobic SAM surfaces that exacerbates interfacial voids. The imidazole derivatives not only form strong Pb–N coordination bonds with undercoordinated Pb²⁺ but also modulate the surface energy of Me-4PACz, enabling the growth of pinhole-free perovskite films with preferential crystal orientation. The champion device with 4,5-Di-I modification achieves a power conversion efficiency (PCE) of 24.10%, with a V_OC enhancement from 1.12 V to 1.14 V, while maintaining 91% of initial PCE after 1300 h in N₂ atmosphere (25 °C), demonstrating superior stability under ISOS-L-2 protocols. This work establishes a universal strategy for interfacial multifunctionality design, proving that simultaneous defect suppression and crystallization control can break the long-standing trade-off between efficiency and stability in solution-processed photovoltaics. Full article

The hole-transport layer (HTL) plays a pivotal role in engineering high-performance inverted perovskite solar cells (PSCs), as it governs both hole extraction/transport dynamics and critically impacts the crystallization quality of the perovskite absorber layer in device architectures. Recent advancements have highlighted self-assembled monolayers (SAMs) as promising candidates for next-generation HTL materials in inverted PSCs due to their intrinsic advantages over conventional counterparts. These molecularly engineered interfaces demonstrate superior characteristics including simplified purification processes, tunable molecular structures, and enhanced interfacial compatibility with device substrates. This review systematically examines the progress, existing challenges, and future prospects of SAM-based HTLs in inverted photovoltaic systems, aiming to establish a systematic framework for understanding their structure–property relationships. The review is organized into three sections: (1) fundamental architecture of inverted PSCs, (2) molecular design principles of SAMs with emphasis on head-group functionality, and (3) recent breakthroughs in SAM-engineered HTLs and their modification strategies for HTL optimization. Through critical analysis of performance benchmarks and interfacial engineering approaches, we elucidate both the technological merits and inherent limitations of SAM implementation in photovoltaic devices. Furthermore, we propose strategic directions for advancing SAM-based HTL development, focusing on molecular customization and interfacial engineering to achieve device efficiency and stability targets. This comprehensive work aims to establish a knowledge platform for accelerating the rational design of SAM-modified interfaces in next-generation optoelectronic devices. Full article

This study presents an effective strategy to enhance the efficiency and stability of perovskite solar cells (PSCs) by integrating neodymium-doped upconversion nanoparticles (UCNPs) coated with a TiO₂ shell into the mesoporous electron transport layer. The incorporation of neodymium (Nd³⁺) as a novel sensitizer shifts the near-infrared (NIR) absorption band away from the water vapor absorption region in the solar spectrum. This modification enables UCNPs to efficiently convert NIR light into ultraviolet (UV) and blue wavelengths, which are readily absorbed by TiO₂, generating additional charge carriers and improving photovoltaic performance. The optimized PSCs, fabricated by blending 30% UCNPs@TiO₂ with commercial TiO₂ paste, achieved a peak power conversion efficiency (PCE) of 21.71%, representing a 20.4% improvement over the control (18.04%). This enhancement included a 0.9% increase in the open-circuit voltage (V_oc), a 6.6% rise in the short-circuit current density (J_sc), and an 11.9% boost in the fill factor (FF). Additionally, the optimized PSCs exhibited remarkable stability, retaining over 90% of their initial PCE after 900 h in humid conditions, compared to only 70% for the control. These improvements result from enhanced light absorption, reduced moisture infiltration, and lower defect-related recombination. This approach provides a promising pathway for developing highly efficient and durable PSCs. Full article

This study analyzes the impact of powder-blasted surface modification on the performance of non-imaging solar concentrators and evaluates a ray-tracing simulation approach to virtual solar power measurements. Powder blasting was applied to poly(methyl methacrylate) (PMMA) sheets to create a rough, Lambertian-like scattering surface, enhancing light trapping and total internal reflection. The effects of this modification were systematically assessed using optical transmission spectroscopy, angular scattering measurements, and solar cell efficiency characterization under standard AM1.5 illumination. The results show that surface roughening significantly improves light redirection toward the concentrator’s edge, enhancing solar cell performance. OptisWorks ray-tracing simulations were employed to model the concentrator’s optical behavior, demonstrating strong agreement (within 5–10% deviation) with experimental data. These findings confirm that surface modification is crucial in optimizing concentrator efficiency and establishing ray tracing as a reliable tool for virtual performance evaluation in photovoltaic applications. Full article

Single-junction perovskite solar cells (PSCs) have been one of the most promising photovoltaic technologies owing to their high-power conversion efficiencies (PCEs) of ~27% and the low-cost fabrication processes involved, which pay off significantly given their distinct structural characteristics. Recently, inorganic hole-transport materials (HTMs) such as nickel oxide (NiO_x) have been developed and received considerable attention for use in OPVs due to their excellent thermal stability, low-cost materials, and compatibility with scalable deposition methods. Here, we summarize the recent progress on inorganic HTMs for PSCs, which can be divided into three categories: NiO_x, copper-based compounds, and emerging new alternatives. The deposition method (sputtering, atomic layer deposition, or a solution-based technique) is one of the most important factors affecting the performance and stability of PSCs. Finally, we review interfacial engineering strategies, such as surface modifications and doping, which can enhance charge transport and extend a device’s lifetime. We also balance the benefits of inorganic HTMs against the key challenges in advancing to commercialization, namely interior defects and environmental degradation. In this review, we summarize the recent progress and challenges toward developing cost-efficient and stable PSCs with inorganic HTMs and provide insights into the future development of these materials. Full article

In recent years, extensive research has been conducted with the aim of developing non-fullerene acceptors as they have a promising ability to drive the development of cost-effective and highly efficient organic solar cells (OSCs). By harnessing the potential of rhodanine-flanked non-fullerene acceptors (NFAs), we proposed eight new A-D-A type NFAs (SBA1–SBA8) through precise end-cap modifications on both sides of the bridging-core unit. We performed various advanced quantum chemical analyses to unveil these designed materials’ potential and compared them with the synthetic reference molecule (R). The proposed NFAs series presented lower binding and excitation energy, along with narrower energy gaps of 2.11 eV and enhanced absorption at 671.20 nm and 719.88 nm in gaseous and chloroform environments, respectively. Furthermore, the optoelectronic and photophysical characterizations related to the electrostatic potential, density of states, reorganization energy of electron and hole mobilities, and transition density matrix analysis reveal that these materials could be efficiently used as acceptor materials for efficient organic photovoltaics. Additionally, to check the impact of charge transfer at the donor: acceptor (D: A) interface, we studied the PTB7-Th:SBA1 D:A analysis and demonstrated a remarkable interface charge transfer phenomenon. Therefore, the engineered SBA1–SBA8 NFAs represent a significant advancement as sustainable and effective options for developing high-performance OSCs. Full article

Semitransparent perovskite solar cells (PSCs) that possess a high-power conversion efficiency (PCE) and high average visible light transmittance (AVT) can be employed in applications such as photovoltaic windows. In this study, a bifacial modification comprising a buried layer of [4-(3,6-Dimethyl-9H-carbazol-9-yl) butyl] phosphonic acid (Me-4PACz) and a surface passivator of 2-(2-Thienyl) ethylamine hydroiodide (2-TEAI) was proposed to enhance device performance. When the concentrations of Me-4PACz and 2-TEAI were 0.3 mg/mL and 3 mg/mL, opaque PSCs with a 1.57 eV perovskite absorber achieved a PCE of 22.62% (with a V_OC of 1.18 V) and retained 88% of their original value after being stored in air for 1000 h. By substituting a metal electrode with an indium zinc oxide electrode, the resulting semitransparent PSCs showed a PCE of over 20% and an AVT of 9.45%. It was, therefore, suggested that the synergistic effect of Me-4PACz and 2-TEAI improved the crystal quality of perovskites and the carrier transport in devices. When employing an absorber with a wider bandgap (1.67 eV), the corresponding PSC obtained a higher AVT of 20.71% and maintained a PCE of 18.73%; these values show that a superior overall performance is observed compared to that in similar studies. This work is conductive to the future application of semitransparent PSCs. Full article

Controlling traps and structural defects in perovskite absorber layers is crucial for enhancing both the device efficiency and long-term stability of perovskite solar cells (PSCs). Here we demonstrate the modification of perovskite films by introducing low-cost green polymers, polysuccinimide (PSI) and polyasparagine (PASP), into the perovskite layer. Structural, morphological and optoelectronic properties of polymer-modified perovskite films were probed by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) and UV-Vis spectroscopy. The incorporation of PSI triggers interactions between the polymer and perovskite, leading to the passivation of surface defects at the grain boundaries and improved morphology of perovskite films. This defect passivation boosted PSC performance, providing power conversion efficiency (PCE) values up to 20.1%. An optimal polymer concentration of 0.1 mg/mL in the perovskite precursor solution was identified for an improvement in the photovoltaic performance. It was shown that the primary factor leading to the observed enhancement in the power conversion efficiency for PSI-modified PSCs is the increase in the lifetime of charge carriers due to the efficient passivation of surface defects and suppression of recombination losses. Additionally, PSI-modified PSCs demonstrated enhanced stability, retaining over 80% of their initial efficiency after 40 days of storage under ambient conditions without encapsulation. The obtained results highlight the effectiveness of green polymer additives in passivating surface defects in perovskite films and provide a viable approach for improving the stability and performance of perovskite solar cells. Full article

Phenothiazine-based photosensitizers bear the intrinsic potential to substitute various expensive organometallic dyes owing to the strong electron-donating nature of the former. If coupled with a strong acceptor unit and the length of N-alkyl chain is appropriately chosen, they can easily produce high efficiency levels in dye-sensitized solar cells. Here, three novel D-A dyes containing 1H-tetrazole-5-acrylic acid as an acceptor were synthesized by varying the N-alkyl chain length at its phenothiazine core and were exploited in dye-sensitized solar cells. Differential scanning calorimetry showed that the synthesized phenothiazine derivatives exhibited behavior characteristic of molecular glasses, with glass transition and melting temperatures in the range of 42–91 and 165–198 °C, respectively. Based on cyclic and differential pulse voltammetry measurements, it was evident that their lowest unoccupied molecular orbital (LUMO) (−3.01–−3.14 eV) and highest occupied molecular orbital (HOMO) (−5.28–−5.33 eV) values were fitted to the TiO₂ conduction band and the redox energy of I⁻/I₃⁻ in electrolyte, respectively. The experimental results were supported by density functional theory, which was also utilized for estimation of the adsorption energy of the dyes on the TiO₂ and its size. Finally, the compounds were tested in dye-sensitized solar cells, which were characterized based on current–voltage measurements. Additionally, for the compound giving the best photovoltaic response, the efficiency of the DSSCs was optimized by a photoanode modification involving the use of cosensitization and coadsorption approaches and the introduction of a blocking layer. Subsequently, two types of tandem dye-sensitized solar cells were constructed, which resulted in an increase in photovoltaic efficiency to 6.37%, as compared to DSSCs before modifications, with a power conversion value of 2.50%. Full article

The rise in photovoltaic (PV) energy utilization has led to increased research on its functioning, as its accurate modeling is crucial for system simulations. However, capturing nonlinear current–voltage traits is challenging due to limited data from cells’ datasheets. This paper presents a novel enhanced version of the Brown-Bear Optimization Algorithm (EBOA) for determining the ideal parameters for the circuit model. The presented EBOA incorporates several modifications aimed at improving its searching capabilities. It combines Fractional-order Chaos maps (FC maps), which support the BOA settings to be adjusted in an adaptive manner. Additionally, it integrates key mechanisms from the Hippopotamus Optimization (HO) to strengthen the algorithm’s exploitation potential by leveraging surrounding knowledge for more effective position updates while also improving the balance between global and local search processes. The EBOA was subjected to extensive mathematical validation through the application of benchmark functions to rigorously assess its performance. Also, PV parameter estimation was achieved by combining the EBOA with a Newton–Raphson approach. Numerous module and cell varieties, including RTC France, STP6-120/36, and Photowatt-PWP201, were assessed using double-diode and single-diode PV models. The higher performance of the EBOA was shown by a statistical comparison with many well-known metaheuristic techniques. To illustrate this, the root mean-squared error values achieved by our scheme using (SDM, DDM) for RTC France, STP6-120/36, and PWP201 are as follows: (8.183847 × 10⁻⁴, 7.478488 × 10⁻⁴), (1.430320 × 10⁻², 1.427010 × 10⁻²), and (2.220075 × 10⁻³, 2.061273 × 10⁻³), respectively. The experimental results show that the EBOA works better than alternative techniques in terms of accuracy, consistency, and convergence. Full article

Photovoltaic technology has become one of the major renewable ways to generate electric power. However, the mismatch between the incident solar spectrum and photo-electric response efficiency of solar cells severely constrains their performance. Hence, spectral modification technologies, e.g., up-conversion (UC), down-conversion (DC), and luminescent down-shifting (LDS) technologies have been applied widely in the photovoltaic field to reform the incident spectrum to match the best response band possible. In this paper, we review the latest developments of the three technologies above in terms of material selection, optical characteristics, and photovoltaic performance. It is found that the three most popular materials for conversion are NaYF₄: Er³⁺, Yb³⁺, and Yb³⁺. The excitation bands for the three technologies are 800–1550 nm, 250–488 nm, and 250–488 nm, respectively, while the emission bands are 523–669 nm, 520–1031 nm, and 490–1010 nm, respectively. Furthermore, issues hindering the development of spectral modification technologies are pointed out, e.g., low absorption efficiency, poor quantum conversion efficiency, and hurdles in commercialization. Finally, suggestions and solutions to address the above-mentioned issues are provided. Full article

Perovskite solar cells (PSCs) are considered the most promising photovoltaic devices to replace silicon-based solar cells because of their low preparation cost and high photoelectric conversion efficiency (PCE). Reducing defects in perovskite films is an effective means to improve the efficiency of PSCs. In this paper, a lead chelator was selected and mixed into hole transport layers (HTLs) to design and prepare mesoporous PSCs with the structure of ITO/PTAA(BCP)/Al₂O₃/PVK/PCBM/BCP/Ag, and its modification effect on the buried interface at the bottom of the perovskite layer in the mesoporous structure was explored. The experimental results show that in the presence of mesoporous alumina, the lead chelator can still play a role in modifying the bottom of the perovskite film. The use of lead chelator as passivation material added to the HTL can effectively reduce the residue of dimethyl sulfoxide (DMSO) and decrease the defects at the bottom of the perovskite film, which dramatically improves the device performance. The PCE of the device is increased from 18.03% to 20.78%, which is an increase of 15%. The work in this paper provides an effective method to enhance the performance of PSCs. Full article

The efficiency and reproducibility of perovskite solar cells (PSCs) are significantly influenced by the purity of lead iodide (PbI₂) in the raw materials used. Pb(OH)I has been identified as the primary impurity generated from PbI₂ in water-based synthesis. Consequently, a comprehensive investigation into the impact of Pb(OH)I impurities on film and device performance is essential. In this study, PbI₂, with varying stoichiometries, was synthesized to examine the effects of different Pb(OH)I levels on perovskite device performance. The characterization results revealed that even trace amounts of Pb(OH)I impede the formation of precursor prenucleation clusters. These impurities also increase the energy barrier of the α-phase and facilitate the transition of the intermediate phase to the δ-phase. These effects result in poor perovskite film morphology and sub-optimal photovoltaic device performance. To address these issues, a cost-effective method for preparing high-stoichiometry PbI₂ was developed. The formation of Pb(OH)I was effectively inhibited through several strategies: adjusting solution pH and temperature, modifying material addition order, simplifying the precipitation–recrystallization process, and introducing H₃PO₂ as an additive. These modifications enabled the one-step synthesis of high-purity PbI₂. PSCs prepared using this newly synthesized high-stoichiometry PbI₂ demonstrated photovoltaic performance comparable to those fabricated with commercial PbI₂ (purity ≥ 99.999%). Our novel method offers a cost-effective alternative for synthesizing high-stoichiometry PbI₂, thereby providing a viable option for the production of high-performance PSCs. Full article