Application In Photovoltaic Cells Research Articles

First-principles calculations of the effect of vacancy defects on the optoelectronic and mechanical properties of the double perovskite Cs2NaInCl6

Abstract Cs2NaInCl6 have become a hot research topic in perovskite optoelectronic materials. However, there is no research on the vacancy properties of Cs2NaInCl6 at present. Herein，using density functional theory-based first-principles calculations, the impact of Cs, Na, In, and Cl single vacancies on the microstructure, electronic, optical, and mechanical properties of the double perovskite Cs2NaInCl6 were investigated. The research shows that the presence of vacancy defects leads to distortion of the Cs2NaInCl6 double perovskite structure and an increase in the unit cell volume. Cs vacancy (VCs) and Na vacancy (VNa) cause an increased band gap for Cs2NaInCl6, by 2.92eV and 3.1eV respectively, without changing the characteristics of the initial direct band gap; VIn and VCl cause the intrinsic semiconductor Cs2NaInCl6 to transform into p-type and n-type semiconductors, respectively, altering the conductivity of Cs2NaInCl6. In terms of optical properties, different vacancy defect systems exhibit different absorption abilities in the visible and ultraviolet light ranges. The defect system overall improves light absorption in the low energy region, and as the incident photon energy increases, the material exhibits the best optical performance at around 15eV. In addition, it is found that VCs, VNa, and VIn caused blue shift in the absorption edge of Cs2NaInCl6, while VCl caused red shift in the absorption edge. In terms of mechanical properties, defects cause varying degrees of reduction in Young's modulus (E), shear modulus (G), and bulk modulus (B) of Cs2NaInCl6, which to some extent alters the mechanical properties of Cs2NaInCl6. These research results provide theoretical guidance for understanding the influence of vacancies on the properties of Cs2NaInCl6 double perovskite and optimizing the performance of perovskite optoelectronic devices, and they also enhance its applications in photovoltaic cells, optoelectronic sensors, and other optoelectronic coupling devices.

FP-LMTO simulation of the physical properties of arsenic-based binary XAs(X = Sc, and Al) compounds

This paper presents a simulation of the structural and optoelectronic properties of Scandium Arsenide (ScAs) and Aluminum Arsenide (AlAs) compounds. Theoretical modeling was performed using ab initio first-principles calculations, specifically the density functional theory (DFT), and the Mindlab numerical software. The software used two methods: the full-potential muffin-tin orbital method (FP-LMTO) and the full-potential plane-wave method (FP-LAPW). These two methods are employed to solve the Schrödinger equation. The exchange correlation effects have been computed using two different approximations: the generalized gradient approximation (GGA) and the local density approximation (LDA). Our findings indicate that the zinc blende structure (B3) is the stable phase, while the Wurtzite phase (B4) is metastable for the AlAs compound. On the other hand, the ScAs compound crystallizes in the NaCl phase (B1). The AlAs compounds undergo three phase transitions: [Formula: see text], [Formula: see text] and [Formula: see text]. In contrast, ScAs does not undergo any transition. The obtained results for equilibrium energies, lattice parameters and gap energies are in closer agreement with the experimental and theoretical data. The AlAs compound exhibits a semiconducting character, while ScAs exhibits a semi-metallic character. Additionally, the refractive index of these two compounds is similar to that of silicon, which is crucial for their application in photovoltaic cells.

Energy storage comparison of chemical production decarbonization: Application of photovoltaic and solid oxide electrolysis cells

The fossil fuel driven chemical production leads to significant greenhouse emission, and the low-carbon emission technologies are necessary for carbon neutrality. The integration of solid oxide electrolysis cells (SOEC) and H2-O2 combustion can replace the fossil fuel and supply high-temperature heat for reactions. However, the energy demand keeps consistent but the renewable energy fluctuates with time. Therefore, energy storage is important for such a change. Clean fuel replacement and electrification are applied in a case study of ethylene plant, which requires 147 MW of clean fuel and 91.36 MW of grid power. Photovoltaic (PV) solar energy drives SOEC and liquefied H2, compressed H2, compressed air energy storage (CAES) are compared. A mixed integer nonlinear programming model is proposed to evaluate decarbonization effect and cost, which are balanced by multi-objective optimization. The results show that the liquefied H2 is superior to other choices because of the high efficiency. The hydrogen of 126.27 MW is the optimal point, which requires 415 MW SOEC and PV panels. Also, this study proposes that the power grid should communicate with energy consumers such as chemical plants to ensure the energy storage method, or supply renewable energy directly, which avoids energy loss and unreasonable energy transition.

Interpretable machine learning boosting the discovery of targeted organometallic compounds with optimal bandgap

Organometallic compounds (OMCs) have attracted tremendous attention in various fields, such as photovoltaic cell and high-k dielectric application, due to their beneficial properties. Despite their potential, the progression of OMCs into industrial applications is hindered by the limited databases available for their properties and the absence of efficient surrogate models. To address this, in this study, optimally selected feature-based surrogate models for predicting the electronic properties of OMCs are constructed via various multiscale features and extensive database. To this end, high-throughput calculation was performed to obtain electronic properties of more than 18k materials generally known as organometallics, augmenting around 12k organic materials obtained from the public open data set, OMDB-GAP1. For generating features closely related to OMCs, descriptors encapsulating the information ranging local to global, also other widely-used composition-, structure-based features (more than 3.5k in total) were employed. Among these descriptors, we identified 48 critical features that elucidates the physicochemical underpinnings of OMCs’ properties, suggesting their impact on the properties of OMCs. The light gradient boosting machine model achieved high-accuracy predictions across the entire database with just 1 % of the total descriptors, sufficiently compared to the entire sets (decreased of around 0.01 by R2 score and 0.01 eV by MAE). Furthermore, the efficacy of active learning process was demonstrated to find OMCs with optimal properties rapidly. As a result, expected improvement outperforms other methods by identifying 69 % of the target materials only searching 46 % of the total search space. Our constructed platform with a high-throughput calculated database can pave the way for the rapid screening of OMCs for the targeted industrial application, and suggest a comprehensive grasp of the intrinsic properties of OMCs and related compounds.

Analysis of photovoltaic operation characteristics and application of photovoltaic cells in Chongqing

Analysis of photovoltaic operation characteristics and application of photovoltaic cells in Chongqing

Some Polyaniline Blends Films Physical Characteristics

The casting technique has been successfully used to prepare films with polyaniline (PAni) blends. Films made from the (PMMA ,PAni ), PS, and POE at consistent concentrations have a thickness of 50 micro meters. By using XRD and FTIR spectroscopy, the PAni Blends films are identified. Using this method, the presence of the films' distinctive bonds was discovered. Electrical characteristics showed that, the conductivity of PAni blend sheets measured at room temperature is as follows: for PAni blends made with PMMA, PS, and PEO, respectively: (5.18, 9.23 and 0.12) 10-9 S.cm-1. The tensile stress and hardness numbers of the numerous PAni blend films can differ from one another depending on the mechanical characteristics. The results also indicated that the polymers can be used with a very thin layer in photovoltaic cell applications.

Some Polyaniline Blends Films Physical Characteristics

The casting technique has been successfully used to prepare films with polyaniline (PAni) blends. Films made from the (PMMA ,PAni ), PS, and POE at consistent concentrations have a thickness of 50 micro meters. By using XRD and FTIR spectroscopy, the PAni Blends films are identified. Using this method, the presence of the films' distinctive bonds was discovered. Electrical characteristics showed that, the conductivity of PAni blend sheets measured at room temperature is as follows: for PAni blends made with PMMA, PS, and PEO, respectively: (5.18, 9.23 and 0.12) 10-9 S.cm-1. The tensile stress and hardness numbers of the numerous PAni blend films can differ from one another depending on the mechanical characteristics. The results also indicated that the polymers can be used with a very thin layer in photovoltaic cell applications.

Geometry, reactivity descriptors, light harvesting efficiency, molecular radii, diffusion coefficient, and oxidation potential of RE(I)(CO)3Cl(TPA-2, 2′-bipyridine) in DSSC application: DFT/TDDFT study

Dye-sensitized solar cells (DSSCs) are an excellent alternative solar cell technology that is cost-effective and environmentally friendly. The geometry, reactivity descriptors, light-harvesting efficiency, molecular radii, diffusion coefficient, and excited oxidation state potential of the proposed complex were investigated. The calculations in this study were performed using DFT/TDDFT method with B3LYP functional employed on the Gaussian 09 software package. The calculations were used the 6–311 + + G(d, p) basis set for the C, H, N, O, Cl atoms and the LANL2DZ basis set for the Re atom, with the B3LYP functional.. The balance of hole and electron in this complex has increased the efficiency and lifetime of DSSCs for photovoltaic cell applications. The investigated compound shows that the addition of the TPA substituent marginally changes the geometric structures of the 2, 2′-bipyridine ligand in the T1 state. As EDsubstituents were added to the compound, the energy gap widened and moved from ELUMO (− 2.904 eV) (substituted TPA) to ELUMO (− 3.122 eV) (unsubstituted). In the studying of solvent affects; when the polarity of the solvent decreases, red shifts appears in the lowest energy an absorption and emission band. Good light-harvesting efficiency, molecular radii, diffusion coefficient, excited state oxidation potential, emission quantum yield, and DSSC reorganization energy, the complex is well suited for use as an emitter in dye-sensitized solar cells. Among the investigated complexes mentioned in literature, the proposed complex was a suitable candidate for phosphorescent DSSC.

Nitrogen-doped graphene quantum dots/ polyvinyl alcohol nanocomposite for photon management: Application in CIGS photovoltaic cells

The efficiency (η) of copper indium gallium selenide (CIGS) solar cells has been hampered by absorption losses that happen within the ZnO and CdS layers. A photon downconversion layer created from polyvinyl alcohol (PVA) and nitrogen-doped graphene quantum dots (NGQDs) composite (NGQDs/PVA) was implemented on the top of the cell to overcome this obstacle. Notably, the NGQDs/PVA layers, prepared at spin speeds of 3000, 4000, and 5000 rpm, exhibited optimal characteristics, demonstrating superior light absorption at low wavelengths along with elevated transmittance at longer wavelengths. The η was found to be highest for the layer prepared at 4000 rpm, accompanied by elevated values of short-circuit current (Jsc), open-circuit voltage (Voc), and fill factor (FF). Consequently, Cell #2 incorporating the champion NGQDs/PVA layer outperformed all other CIGS photovoltaic cells, showcasing an impressive enhancement of 8.96 % in Jsc, 1.62 % in Voc, 2.03 % in FF, and an overall η of 11.51 %. This champion cell significantly improves the performance of CIGS photovoltaics.

Optoelectronic properties, stability, and thermodynamic properties of 2D XSn2N4 (X = Cr, Mo, W) monolayers

Through first-principle calculations, we show innovative CrSn2N4, MoSn2N4 and WSn2N4 monolayers with high stability. The current results reveal that CrSn2N4 is a conductor-like material with metallic propensity, while MoSn2N4 and WSn2N4 are indirect bandgap semiconductors with narrow bandgaps of 0.16 eV and 0.39 eV, respectively. The mechanical characteristics of CrSn2N4, MoSn2N4, and WSn2N4 are stable, with Young's modulus and Poisson's ratio greater than those of graphene and C2F4. Besides, the thermodynamic characteristics were tested, and it was observed that the thermodynamic stability of MoSn2N4 was superior to the other two materials. The optical properties show the layered MoSn2N4 and WSn2N4 have strong light absorption and a wide absorption range, which have the potential for application in photovoltaic cells and devices. The spectral limits of the maximum efficiencies of 22 % and 14 % for MoSn2N4 and WSn2N4, respectively, are greater than those of SnO2. Thus, the three novel two-dimensional materials have potential applications in the area of photoelectric devices.

Evaluating the reactivity of polyvinyl alcohol/graphene nanocomposites

The synthesis and characterization of polyvinyl alcohol (PVA)/graphene nanocomposite films, through the solution casting technique, were thoroughly explored and studied. The integration of varying concentrations of graphene was systematically explored to enhance the structural and optical attributes of the PVA matrix. Comprehensive characterization employing X-ray Diffraction (XRD), Fourier-Transform Infrared (FTIR) Spectroscopy, and Ultraviolet–Visible (UV–Vis) Spectrophotometry revealed significant interactions between PVA and graphene, manifesting in a decrease in crystallinity and optical bandgap with increasing graphene content. DFT:B3LYP/6-31g(d,p) quantum mechanical level, corroborated these findings by indicating a diminished HOMO/LUMO bandgap energy. Additionally, molecular electrostatic potential mapping underscored an increase in PVA's reactivity post-graphene integration. The investigation further extends to evaluating global reactivity descriptors, providing insights through PDOS plots and QSAR analysis. The outcomes of this research underscore the potential of PVA/graphene nanocomposites for next-generation applications in flexible photovoltaic cells, transistors, and diodes.

Ab initio investigation of mechanical, electronic and optical properties in the orthorhombic [formula omitted] inorganic perovskite

This study employs a first-principles approach to comprehensively investigate the structural, electronic, elastic, and optical properties of two distinct inorganic perovskite phases of CsPbI3, identified as C–CsPbI3 and O–CsPbI3. Utilizing the Wien2K code, simulations are conducted employing various density functional theory (DFT) approximations, including local density approximation (LDA), generalized gradient approximation (GGA), the modified Becke–Johnson potential (mBJ), and the Tran-Blaha modified Becke–Johnson potential (TB-mBJ). Our analysis demonstrates that the orthorhombic phase exhibits greater energetic stability and mechanical robustness compared to the cubic phase. Furthermore, optical analyses reveal a direct bandgap in the compound, with key parameters calculated and interpreted. Notably, both phases demonstrate exceptional electronic, mechanical, and optical properties, suggesting their potential applications in optoelectronics, photovoltaics, and photovoltaic cells. Consequently, this study positions both the cubic and orthorhombic phases of CsPbI3 as promising materials warranting further exploration and development in these technological domains.

Theoretical insights into the electronic and optical properties of lithium-based perovskite for solar cell applications

This study explores the influence of central metals and halide anions on the structural, electronic, and optical properties of LiBX3 perovskites (B = Ge, Sn, Pb, X = F, Cl, Br, I) in both unit cell and supercell configurations, aiming for potential applications in photovoltaic devices. Density functional theory calculations reveal that increasing the atomic radius of halogens and central metals directly affects the lattice parameters. Our research indicates that Ge and Sn-based perovskites (except for unit cell LiSnF3) exhibit semiconductor properties with direct band gap energies, while Pb-based perovskites in the unit cell configuration display an indirect band gap. Key factors contributing to the reduction of the band gap energy in most materials include the expansion of the atomic radius of halogens and the examination of perovskites in their supercell state, such that perovskites like LiGeI3, LiSnI3, and LiPbI3 represent a band gap value of 0.001 eV in their supercell configuration. Furthermore, the light absorption characteristics of these perovskites demonstrate a high absorption coefficient ranging from 105 to 106. Among the studied compounds, I-based perovskites exhibit the highest static dielectric constant, surpassing other perovskite variants, with for example, unit cell and supercell of LiSnI3 having static dielectric constant values of 38 and 70, respectively. Additionally, the investigation of perovskites in their supercell form suggests that the number of atoms in the network does not significantly impact their optical properties. In conclusion, based on various analyses, I-based perovskites are proposed as ideal candidates for application in Photovoltaic Solar Cells (PSCs).

Comprehensive DFT investigation of ternary thallium tetragonal crystals: assessing their viability for solar cell applications

To ascertain the suitability of the TlInX2 (X = S, Se, Te) tetragonal structures for photovoltaic applications, first-principles calculations were carried out using the pseudopotential plane wave method to assess the structural, electronic, elastic, and optical characteristics of the considered compounds via the DFT software CASTEP. For all three compounds, our calculated structural parameters were in excellent agreement with both the experimental and previous theoretical results. Our calculations provided the first predicted elastic constants for the TlInS2, TlInSe2 and TlInTe2 compounds. The three tetragonal systems were mechanically stable and exhibited pronounced and noticeable elastic anisotropy. Analysis of the optical properties revealed that TlInX2 (X = S, Se, Te) exhibited distinct absorption in the ultraviolet radiation range and pronounced optical anisotropy. The calculated bandgap values obtained using the HSE06 hybrid functional were 1.68 eV, 1.38 eV, and 1.36 eV for TlInS2, TlInSe2 and TlInTe2, respectively. These findings are of significant interest because they categorize all three compounds as promising candidates for use in photovoltaic cell applications.

Binary ZnS–ZnO films as an alternative buffer layer for solar cell applications

In this research, binary ZnS–ZnO films were fabricated by a two-step process, offering an alternative buffer layer solution for photovoltaic solar cell applications. ZnS films were attained through thermal evaporation, after which they were annealed in air at separate temperatures resulting in films containing both ZnS and ZnO phases. Structural, electrical, ellipsometric, optical, and surface properties were examined in detail to elucidate their applicability as a buffer layer in photovoltaic applications. X-ray diffraction patterns revealed that the films exhibit cubic ZnS and hexagonal ZnO crystal structures, wherein crystallite size is augmented with higher annealing temperatures. ZnS films exhibited a needle-shaped surface morphology, as confirmed through atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM) images. Annealing caused noteworthy modifications on the surfaces of the films. Additionally, absorption spectra denote two distinct absorption regions forming as a result of the annealing process, possibly indicating the emergence of ZnS and ZnO phases. Photoluminescence analyses demonstrate that binary ZnS–ZnO films exhibit greater emission intensities than single-phase ZnS films. Additionally, the annealing process caused the electrical resistivity of films to reduce from 1.28 × 105 to 3.84 × 101 Ω cm. These results suggest that binary ZnS–ZnO films produced via annealing can be considered as promising buffer layers in potential photovoltaic solar cell applications.

First-principles calculations to investigate impact of doping by chalcogen elements on the electronic, structural, and optical properties of SrTiO3 compounds

Doping techniques are commonly utilized to effectively modify the physical properties of a desired compound. In this study, we employed the first-principles DFT calculations with a GGA + TB-mBJ approach as implemented by the Wien2k code, by investigating the effects of oxygen group element concentrations on the structural, electronic, and optical properties of the perovskite substance SrTiO3. We calculated the formation energies of each doped structure to assess the viability of synthesis. The band gap is equal to 1.355 eV, 0.653 eV, and 0.632 eV for 12.5 % S, Se, and Te doped SrTiO3, respectively. For the pure SrTiO3, the band gap is 2.584 eV. According to our findings, raising the chalcogen concentrations resulted in a considerable decrease in band gaps and an improvement in the ability to absorb light in the visible range (380–790 nm), exceeding 105 cm−1 for Te doped SrTiO3 (STO). At zero frequency, the dielectric constant was found (ε1 (0)) to be 4.432 for SrTiO3 pure and 6.332 for SrTiO3 doped with Te (12.5 %) in GGA-PBE and (ε1 (0)) = 4.432 and 12.217 for GGA + mBJ. The optical conductivity of SrTO3 doped with Te is determined to be 0.322 * 104 /Ω.cm, in comparison to a value of 0.377 * 104/Ω.cm for mBJ. Our research revealed that raising the chalcogen concentrations significantly enhanced the electrical conductivity, as predicted, along with improvements in optical conductivity and reflectivity. SrTiO3-xYx (Y = S, Se, or Te) represents one of our quaternary alloys, demonstrating substantial potential as a promising material for advanced photovoltaic and solar cell applications. Our findings revealed that the doped materials exhibited significantly high absorption rates and productivity. We also examined additional optical parameters, including optical band gap, Urbach energy, and optical conductivity.

Electronic, Elastic, Optical, and Thermodynamic Properties Study of Ytterbium Chalcogenides Using Density Functional Theory

In this study, the structural, electronic, optical, elastic, and thermodynamic properties of Ytterbium chalcogenides YbX (X = S, Se and Te) were computed within the first principles using generalized gradient approximation (GGA) as implemented in the pseudopotential plane wave approach. The equilibrium total energy for YbX (X = S, Se, and Te) was calculated as a function of the energy cutoff, k-point grid, and lattice parameter. An optimized lattice parameter of 5.6, 5.66, and 6.136 Å were calculated for YbS, YbSe, and YbTe, respectively. The energy band gaps of YbS, YbSe, and YbTe computed are 1.14, 1.32, and 1.48 eV, respectively. In addition, the low band gap (less than 3 eV) for ytterbium chalcogenides indicated that they may have potential applications in photovoltaic cells and laser diodes. Moreover, the negative dielectric function value for a certain frequency range indicates that these compounds are suitable for specific optical and microwave circuit applications. The result of elastic and thermodynamic property computation reveals that ytterbium chalcogenides are mechanically and thermodynamically stable, which can be useful in a variety of electronic device applications.

Comparison Between Perovskite and Silicon for Photovoltaic Cell Applications and Future Industrial Prospects

Environmental concerns have evolved into an essential focal point within contemporary human progress. An increasing number of individuals are recognizing the paramount significance of safeguarding our environment and are actively engaged in crafting a sustainable developmental framework. An integral facet of sustainable progress is the adoption of clean energy, representing a pivotal paradigm shift in the global energy landscape. One remarkable manifestation of this shift is the utilization of photovoltaic (PV) cells, which adeptly transmute radiant light energy into electrical power. This paper delves into an exploration of the prevailing silicon photovoltaic cells widely accessible in the market, while also delving into the realm of perovskite photovoltaic cells, an experimental yet highly promising avenue. It endeavors to juxtapose these two technologies across various dimensions, including energy conversion efficiency, overall cost implications, and environmental repercussions. Evidently, silicon and perovskite technologies manifest distinct advantages and drawbacks in different contexts. It is unequivocally established that both forms of photovoltaic cells hold profound implications for the future trajectory of energy consumption and the overarching ethos of sustainable development.

Predicting band gaps of ABN3 perovskites: an account from machine learning and first-principle DFT studies.

The present paper is primarily focused on predicting the band gaps of nitride perovskites from machine learning (ML) models. The ML models have been framed from the feature descriptors and band gap values of 1563 inorganic nitride perovskites having formation energies <-0.026 eV and band gaps ranging from ∼1.0 to 3.1 eV. Four supervised ML models such as multi-layer perceptron (MLP), gradient boosted decision tree (GBDT), support vector regression (SVR) and random forest regression (RFR) have been considered to predict the band gaps of the said systems. The accuracy of each model has been tested from mean absolute error, root-mean-square error and determination coefficient R2 values. The bivariate plots between the predicted and input band gaps of the compounds for both the training and test datasets have also been estimated. Additionally, two ABN3-type nitride perovskites CeBN3 (B = Mo, W) have been selected and their electronic band structures and optoelectronic properties have been studied from density functional theory (DFT) calculations. The band gap values of the said compounds have been estimated from DFT calculations at PBE, HSE06, G0W0@PBE, G0W0@HSE06 level of theories. The present study will be helpful in exploring the ML models in predicting the band gaps of nitride perovskites which in turn may bear potential applications in photovoltaic cells and optical luminescent devices.

Elaboration and Characterization of Transparent Electrodes of ZnO Doped Al for Application in Organic Photovoltaic Cells

Elaboration and Characterization of Transparent Electrodes of ZnO Doped Al for Application in Organic Photovoltaic Cells