Solar Cell Applications Research Articles

Computational insights into transition metal-based BaCoX3 (X = Cl, Br, I) halide perovskites for spintronics, photovoltaics, and renewable energy devices

Ab-initio simulations using density functional theory (DFT) were employed to investigate the structural, mechanical, electronic, magnetic, optical, and thermoelectric properties of halide perovskites \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {BaCoX}_3$$\\end{document} (X = Cl, Br, I). Structural optimization and mechanical stability assessments confirm the reliability of these perovskites in a hexagonal P\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$6_3$$\\end{document}mc symmetry. The stability of the ferromagnetic phase was validated through total crystal energy minimization via Murnaghan’s equation of state. Electronic band structures and density of states, derived from the generalized gradient approximation (GGA), reveal a semiconducting ferromagnetic nature in the spin up channel, spotlighting their potential in semiconductor spintronic applications. Phonon dispersion analysis of \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {BaCoCl}_3$$\\end{document} and \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {BaCoBr}_3$$\\end{document} revealed positive phonon modes throughout the entire Brillouin zone, confirming their dynamical stability. In contrast, \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {BaCoI}_3$$\\end{document} demonstrated dynamical instability. The elastic constants confirm the mechanical stability and ductile nature of the perovskites. Optical and dielectric properties of these perovskites show significant UV absorption and photoconductivity, making them highly suitable for optoelectronic and solar cell applications. Finally, transport properties, such as the Seebeck coefficient, electrical conductivity, thermal conductivity, power factor, and figure of merit (ZT) unveil their exceptional thermoelectric performance. Combining half-metallic ferromagnetic traits with superior thermoelectric and optoelectronic performance positions \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {BaCoX}_3$$\\end{document} compounds as exceptional candidates for applications in spintronics, optoelectronics, and thermoelectrics. This comprehensive investigation demonstrates their ability to excel across a diverse array of advanced technological applications.

Computational Insight into the Optoelectronic and Chemical Reactivity Properties of Metal-Free Phenothiazine Based D-π-A Dye-Sensitizers for Solar Cells Application: DFT and TD-DFT Methods

Computational Insight into the Optoelectronic and Chemical Reactivity Properties of Metal-Free Phenothiazine Based D-π-A Dye-Sensitizers for Solar Cells Application: DFT and TD-DFT Methods

Metal chalcogenide electron extraction layers for nip-type tin-based perovskite solar cells

Tin-based perovskite solar cells have garnered attention for their biocompatibility, narrow bandgap, and long thermal carrier lifetime. However, nip-type tin-based perovskite solar cells have underperformed largely due to the indiscriminate use of metal oxide electron transport layers originally designed for nip-type lead-based perovskite solar cells. Here, we reveal that this underperformance is caused by oxygen vacancies and deeper energy levels in metal oxide. To address these issues, we propose a metal chalcogenide electron transport layer, specifically Sn(S0.92Se0.08)2, which circumvents the oxygen molecules desorption and impedes the Sn2+ oxidation. As a result, tin-based perovskite solar cells with Sn(S0.92Se0.08)2 demonstrate a VOC increase from 0.48 – 0.73 V and a power conversion efficiency boost from 6.98 – 11.78%. Additionally, these cells exhibit improved stability, retaining over 95% of their initial efficiency after 1632 h. Our findings showcase metal chalcogenides as promising candidates for future nip-type tin-based perovskite solar cell applications.

Fully Non-Fused Ring Electron Acceptors Enable Effective Additive-Free Organic Solar Cells with Enhanced Exciton Diffusion Length.

Low-cost photovoltaic materials and additive-free, non-halogenated solvent processing of photoactive layers are crucial for the large-scale commercial application of organic solar cells (OSCs). However, high-efficiency OSCs that possess all these advantages remain scarce due to the lack of insight into the structure-property relationship. In this work, three fully non-fused ring electron acceptors (NFREAs), DTB21, DTB22, and DTB23, are reported by utilizing a simplified 1,4-di(thiophen-2-yl)benzene (DTB) core with varied alkoxy chain lengths on the thiophene bridge. The material-only costs of these acceptors are only 11-13$ per gram. Importantly, DTB22 has an exciton diffusion length (LD) of up to 25.5nm. The DTB21 and DTB23 exhibit decreased LDs of 20.1 and 23.1nm, respectively. After blending with the polymer donor PBQx-TF, the PBQx-TF:DTB22 film exhibits the fastest hole transfer and the longest carrier recombination lifetime among these OSCs. Consequently, the optimal PBQx-TF:DTB22-based OSC achieves an excellent PCE of 17.00%, which is among the highest values for fully NFREAs. In contrast, the PBQx-TF:DTB21- and PBQx-TF:DTB23-based OSCs show relatively lower PCEs of 15.13% and 15.63%, respectively. Notably, all these OSCs are fabricated using toluene as the solvent, without any additives. Additionally, the DTB22-based OSC also demonstrates good stability, retaining 95% of its initial efficiency after 500 h without encapsulation in a glovebox.

First principles investigation of elastic, electronic and thermoelectric properties of lead-free Cs–X–I (X = Pb, Gd, Nd, Y) perovskites

Abstract Perovskites have become the center of recent research for their possible application in perovskite solar cells, owing to their desirable optical and electronic properties, flexibility, tunability, and low–cost fabrication. Most of the perovskites are however made of lead, which is a highly poisonous element. It is therefore necessary to seek alternative perovskites for this application that are less toxic. This study investigated the elastic, electronic, and thermoelectric properties of Cs–X–I (X = Pb, Gd, Nd, and Y) as possible replacements to the leaded CsPbI3 due to their less toxic nature. The density functional theory was utilized in the computations, with quantum espresso and BoltzTrap packages. The results showed that all the materials were structurally stable. The computed mechanical properties also showed that all the other materials had better elastic constants compared to those of CsPbI3. CsPbI3 was observed to exhibit the lowest band gap, unlike the others. Moreover, the other materials possessed higher elastic constants, electrical conductivities, and lowest thermal conductivities, which are highly needed in the perovskite solar cells. However, an experimental treatment needs to be done on the studied structures in order to confirm the properties obtained in this work.

Regulating Intermolecular Interactions and Film Formation Kinetics for Record Efficiency in Difluorobenzothiadizole‐Based Organic Solar Cells

AbstractThe difluorobenzothiadizole (ffBT) unit is one of the most classic electron‐accepting building blocks used to construct D‐A copolymers for applications in organic solar cells (OSCs). Historically, ffBT‐based polymers have achieved record power conversion efficiencies (PCEs) in fullerene‐based OSCs owing to their strong temperature‐dependent aggregation (TDA) characteristics. However, their excessive miscibility and rapid aggregation kinetics during film formation have hindered their performance with state‐of‐the‐art non‐fullerene acceptors (NFAs). Herein, we synthesized two ffBT‐based copolymers, PffBT‐2T and PffBT‐4T, incorporating different π‐bridges to modulate intermolecular interactions and aggregation tendencies. Experimental and theoretical studies revealed that PffBT‐4T exhibits reduced electrostatic potential differences and miscibility with L8‐BO compared to PffBT‐2T. This facilitates improved phase separation in the active layer, leading to enhanced molecular packing and optimized morphology. Moreover, PffBT‐4T demonstrated a prolonged nucleation and crystal growth process, leading to enhanced molecular packing and optimized morphology. Consequently, PffBT‐4T‐based devices achieved a remarkable PCE of 17.5 %, setting a new record for ffBT‐based photovoltaic polymers. Our findings underscore the importance of conjugate backbone modulation in controlling aggregation behavior and film formation kinetics, providing valuable insights for the design of high‐performance polymer donors in organic photovoltaics.

Micro structures, Morphology and Optical Properties of Sb2O3: WO3, In2O3 Nanostructure Composite Thin Films

This work is concerned with the synthesis of two types of composites thin films (Sb2O3:WO3 and (Sb2O3:In2O3) with different concentrations (0.0,0.05,0.1, and 0.15). The prepared thin films are characterized with the use of the X-ray diffraction atomic force microscope AFM and UV-Vis–infrared spectrophotometer. The structural examination shows that both composite's thin films were polycrystalline with nano size with cubic phase as majority and orthorhombic phase as minority phase. The crystal size decreases from 34.6 to 24.7 and 21.7 nm for (Sb2O3:WO3) and (Sb2O3:In2O3) thin films, respectively. The average roughness shows non-regular growth by increasing the concentration of both oxides. The optical energy band gap shows a red shift for both types of nanostructure thin films, which populate these composited thin films for solar cell applications.

Fabrication of Ripple Structured Silicon Carbide (SiC) Films for Nano‐Grating and Solar Cell Applications

AbstractIn the present study, we aim to investigate the self‐organization of unexplored silicon carbide (SiC) film surfaces under 30 keV oblique Ar+ ions irradiation and hence unprecedented tailoring of optical and electrical characteristics with view of their uses in solar cells, gratings and nano‐ to micro‐scale devices. The surface morphology mainly consisted of triangular shaped nanoparticles which evolves into nanoscale ripple structures with an alignment parallel to the projection of ion beam direction. For the first time, we have demonstrated the fabrication of highly‐ordered ripple patterns with wavelength in visible region over SiC films and applicable as nano‐gratings. The underlying mechanism relies on the structural rearrangement due to transition of film microstructure from amorphous to mixed phase (crystalline, nano‐crystalline and amorphous) and lowering of C=C and C−C vibration modes by the heavier Si atoms. These nanostructured silicon carbide film shows unparalleled optical (energy gap decreases from 4.60±0.4 eV to 3.16±0.2 eV) & electrical characteristics (conductivity increases from 6.6×10−11 to 1.12×10−3 S/m with linear I−V behavior). Thus, we propose that ripple structured SiC films with wide band gap, high refractive index and high electrical conductivity with ohmic behaviour are promising candidates for application as window layer in solar cells and opto‐electronics.

Novel Structures for PV Solar Cells: Fabrication of Cu/Cu2S-MWCNTs 1D-Hybrid Nanocomposite

The production of cost-effective novel materials for PV solar cells with long-term stability, high energy conversion efficiency, enhanced photon absorption, and easy electron transport has stimulated great interest in the research community over the last decades. In the presented work, Cu/Cu2S-MWCNTs nanocomposites were produced and analyzed in the framework of potential applications for PV solar cells. Firstly, the surface of the produced one-dimensional Cu was covered by Cu2S nanoflake. XRD data prove the formation of both Cu and Cu2S structures. The length and diameter of the one-dimensional Cu wire were 5–15 µm and 80–200 nm, respectively. The thickness of the Cu2S nanoflake layer on the surface of the Cu was up to 100 nm. In addition, the Cu/Cu2S system was enriched with MWCNTs. MWCNs with a diameter of 50 nm interact by forming a conductive network around the Cu/Cu2S system and facilitate quick electron transport. Raman spectra also prove good interfacial coupling between the Cu/Cu2S system and MWCNTs, which is crucial for charge separation and electron transfer in PV solar cells. Furthermore, UV studies show that Cu/Cu2S-MWCNTs nanocomposites have a wide absorption band. Thus, MWCNTs, Cu, and Cu2S exhibit an intense absorption spectrum at 260 nm, 590 nm, and 972 nm, respectively. With a broad absorption band spanning the visible–infrared spectrum, the Cu/Cu2S-MWCNTs combination can significantly boost PV solar cells’ power conversion efficiency. Furthermore, UV research demonstrates that the plasmonic character of the material is altered fundamentally when CuS covers the Cu surface. Additionally, MWCN-Cu/Cu2S nanocomposite exhibits hybrid plasmonic phenomena. The bandgap of Cu/Cu2S NWs was found to be approximately 1.3 eV. Regarding electron transfer and electromagnetic radiation absorption, the collective oscillations in plasmonic metal-p-type semiconductor–conductor MWCNT contacts can thus greatly increase energy conversion efficiency. The Cu/Cu2S-MWCNTs nanocomposite is therefore a promising new material for PV solar cell application.

CALCULATION OF ELECTRONIC PROPERTIES OF LiBX3 (B = Pb AND Sn; X = Br, Cl AND I) CUBIC PHASE BY DENSITY FUNCTIONAL THEORY

Perovskite solar cells utilize perovskite as the active material to convert sunlight into electrical energy. Perovskite is a compound with a crystal structure of ABX₃, where A and B are cations, and X is an anion, usually a halide. Research continues to find perovskites with high efficiency. This efficiency is related to the electronic structure, which can be analyzed using Density Functional Theory (DFT). In this study, the electronic structure of cubic phase LiBX₃ perovskites (B = Pb and Sn; X = Br, Cl, and I) is investigated using Quantum ESPRESSO software. Various parameters such as cut-off energy, k-points, and lattice constants were modified to obtain optimal values. From the optimization results, the band gap, DOS, and PDOS values for the six perovskites were obtained. The resulting band gap energy (Eg) are LiPbBr₃ at 1,71 eV, LiPbCl₃ at 1,87 eV, LiPbI₃ at 1,43 eV, LiSnBr₃ at 0,51 eV, LiSnCl₃ at 0,65 eV, and LiSnI₃ at 0,28 eV. These results show that the band gap energy values increase with the change in atomic radius from Sn to Pb and decrease with the change in atomic radius from Cl, Br to I. The electronic structure calculations of LiBX₃ (B = Pb and Sn; X = Br, Cl, and I) show semiconductor properties that have the potential to be used as light-absorbing materials in perovskite solar cells. This study states that LiBX₃ has great potential in solar cell applications and offers a deep understanding of the relationship between crystal structure and its electronic properties.

Impact of oxygen vacancies on the structural, electronic, and optical properties of Cu<i>2</i>O and nitrogen-doped Cu<sub>2</sub>O for optoelectronic applications: a first-principles study

This study utilizes Density Functional Theory (DFT) within the Quantum ESPRESSO framework to explore the effects of oxygen vacancies and nitrogen doping on the electronic structure and optical properties of cuprous oxide (Cu2O). Pristine Cu2O, an intrinsic p-type semiconductor, typically exhibits a direct band gap. Introducing an oxygen vacancy in the absence of a dopant broadens the band structure, leading to both direct and indirect band gap characteristics. In contrast, nitrogen doping transforms the band gap into a direct one, significantly reducing it from 1.97 eV to 1.09 eV, which deviates from previous findings due to potential variations in the initial state of the Cu2O host crystal. Furthermore, spin-polarization effects indicate spin-dependent behaviour within the material. The study also examines the absorption properties of pristine, defective, and nitrogen-doped Cu2O systems using the complex dielectric function. The results show distinct absorption peaks and transitions, with nitrogen-doped Cu2O exhibiting strong absorption in the visible light range, underscoring its potential for solar cell applications.

Enhancing optical properties of Ba-Ni ferrite through nonmagnetic ion doping for sustainable green technologies and renewable energy applications

Barium ferrite powder was produced using a standard ceramic procedure, and its structure and optical properties were investigated. X-ray diffraction analysis (XRD) showed that the powder had a w-type hexagonal structure. The crystallite size was at approximately 35–36 nm, with bulk density and lattice constants increasing as zinc concentration rose. Conversely, X-ray density and porosity decreased with the increasing zinc concentration. This material has useful optical properties, as well as the standard ferrimagnetic properties of barium ferrite, which make it suitable for use in recording media. Ferrimagnetic behavior, which is useful for recording media, occurs because the powder's crystallites have their unit cell axes aligned. Up to the near-infrared part of the spectrum, the powder was found to have a very low absorption coefficient. Both of these properties—an arrangement that gives rise to ferrimagnetism and a corresponding low optical density—make barium ferrite very attractive for high-density recording and microwave applications. Fourier transform infrared spectra of the samples were recorded in the wavenumber range of 400–4000 cm−1 and supported the X-ray diffraction findings by confirming the idea of the formation of W-type hexagonal ferrite by the presence of two prominent peaks at 454 and 591 cm−1 in the FTIR spectra. Zinc addition was also found to enhance the optical properties of the material. The UV–VIS analysis confirms that the band gap energy of Ba-Ni ferrite was indeed reduced by zinc doping. Values decrease from 3.34 eV to 3.20 eV for direct transitions and from 2.96 eV to 2.79 eV for indirect transitions, using Tauc equation. That means that zinc doping enhances the optical properties of Ba ferrite without affecting the hexagonal structure of Ba-Ni ferrite. Moreover, key parameters of optical performance such as the dielectric constant, the extinction coefficient, the penetration depth, and the refractive index show a dramatic increase with a rise in zinc concentration. These attributes make zinc-doped Ba-Ni ferrite a promising optoelectronic material. The material also showed high absorbance in the wavelengths ranging from 334 to 338 nm, which makes it good for the solar cell applications. Overall, zinc-doped Ba-Ni ferrite is a good candidate for sustainable and renewable energy applications. Our study of the optical properties of barium ferrite up to the near-infrared part of the spectrum demonstrated that the powdered material has a very low absorption coefficient. Indeed, the combination of ferrimagnetism and low optical density makes barium ferrite particularly appealing for use in high-density recording and microwave technology applications.

Multi-Noncentrosymmetric Polar Order in 2D Hybrid Lead Chloride with Broadband Emission and High-Temperature Second-Harmonic Generation Switching.

Two-dimensional lead halide perovskites represent a fascinating class of hybrid semiconductors for solar cell, light-emitting, nonlinear optical (NLO), and ferroelectric applications. A notable subset within this category is luminescent ferroelectrics, which have garnered considerable attention for their potential in integrated photoelectronic devices. In this study, we employed an organic amine halogenation strategy (also referred to as halogen engineering), which is renowned for its efficacy in inducing polar order through crystal engineering. Consequently, we synthesized a layered Ruddlesden-Popper (RP) lead chloride comprising 3-chloropropylammonium cations (CPA+), with the chemical formula CPA2PbCl4. This compound features as many as four temperature-dependent crystal phases, with phase transitions observed at T1 = 353.1 K (343.9 K), T2 = 211.7 K (208.6 K), and T3 = 182.0 K (178.2 K) in the heating (cooling) cycles. Employing a multitechnique approach─including thermal analysis, X-ray diffraction, dielectric and pyroelectric current measurements, Raman spectroscopy, and second-harmonic generation (SHG) studies─we determined the mechanisms of the structural phase transitions. Our findings demonstrate polar order of phase II (space group Cmc21), phase III (space group Pna21), and phase IV (space group Pca21), while also confirming the centrosymmetric nature of phase I (space group Cmce). X-ray diffraction data revealed that the I to II PT is of a ferroelectric nature, devoid of ferroelastic strain, a conclusion further supported by pyroelectric measurements. CPA2PbCl4 features negative linear thermal expansion and broadband emission, which transitions to white light above 180 K. Remarkably, CPA2PbCl4 also demonstrates high-temperature SHG on-off switching with a high contrast ratio of 300:1 along with good switching stability, as evidenced by SHG cycling studies at heating/cooling rates ranging from 5 to 50 K/min. This SHG study also sets new standards for the field of SHG switching by providing a method to quantify the thermal responsiveness of SHG-switchable materials using the treq (time requirement) parameter. Overall, our findings show that the halogenation strategy has led to the discovery of a rare example of an RP perovskite exhibiting coexistence of white-light emission, SHG on-off thermal bistability, ferroelectricity, and negative linear thermal expansion.

Template-Assisted Growth of High-Quality α-Phase FAPbI3 Crystals in Perovskite Solar Cells Using Thiol-Functionalized MoS2 Nanosheets.

Formamidinium lead iodide (FAPI) has gained attention for hybrid perovskite solar cell (PSC) applications due to its enhanced stability and narrow bandgap. However, a significant challenge remains in inducing and stabilizing the elusive perovskite "black phase"─photoactive cubic α-FAPI─as the relatively bulky FA+ cations tend to favor the thermodynamically stable nonphotoactive "yellow phase". In this study, we present a templated growth strategy employing thiol-functionalized MoS2 nanosheets as templates. By introduction of 3-mercaptopropionic acid (MPA)-functionalized MoS2 as a growth template, precise control over crystal formation was achieved, favoring the growth of high-quality α-FAPI films. These advanced templated films exhibited substantial improvements in charge transport properties, efficient light absorption, and enhanced charge extraction. As a result, the PSCs achieved a significantly enhanced power conversion efficiency (PCE) compared to the nontemplated control device, increasing from 20.6 to 22.5%. The MoS2-incorporated device also demonstrated excellent shelf stability, maintaining 91% of the initial PCE even after 1600 h of storage without device encapsulation.

Interface properties study of black silicon solar cells with front surface a-Si:H/c-Si heterojunction

Abstract The exceptionally low reflectance of black silicon across a broad wavelength range makes it an intriguing surface texture for solar cell applications. Silicon heterojunction (SHJ) solar cells fabricated on black silicon (Si) formed by dry reactive ion etching (RIE) using inductive coupled plasma (ICP) on n-type Si are explored. The study is focused on the properties of the a-Si:H/c-Si interface, being a key issue for the photovoltaic performance of SHJ. Deep-level transient spectroscopy (DLTS) detected no radiation defect in Si after the etching. The surface of black Si was passivated with an intrinsic a-Si:H layer, followed by the deposition of p-type and n-type a-Si:H on the front and back sides, respectively. The SHJ solar cell photovoltaic performance based on black Si is strongly influenced by defect density at the a-Si:H/Si interface. Admittance spectroscopy and effective charge carrier lifetime measurements demonstrate that interface defect density decreases with the increase of (i)a-Si:H thickness. The value of 0.75 ms effective charge carrier lifetime was reached for single (i) a-Si:H layer passivation and 0.25 ms when (p)a-Si:H was deposited over the intrinsic a-Si:H layer. The measured open circuit voltage (VOC) values for the SHJ solar cells increase with the (i)a-Si:H layer thickness reaching 658 mV. However, the fill factor decreases with increasing (i) a-Si:H layer thickness, limiting the efficiency at the maximum value below 14% due to the thickness uniformity of the a-Si:H layer. The development of conformal growth of a-Si:H is a key issue for further improvement of black Si heterojunction solar cell photovoltaic performance. 

Formamidinium Incorporates into Rb-based Non-perovskite Phases in Solar Cell Formulations.

Organic-inorganic hybrid perovskite materials, such as formamidinium lead iodide (FAPbI3), are among the most promising emerging photovoltaic materials. However, the spontaneous phase transition from the photoactive perovskite phase to an inactive non-perovskite phase complicates the application of FAPbI3in solar cells. To remedy this, alkali metal cations, most often Cs+, Rb+or K+, are included during perovskite synthesis to stabilize the photoactive phase. The atomic-level mechanisms of stabilization are complex. While Cs+dopes directly into the perovskite lattice, Rb+does not, but instead forms an additional non-perovskite phase, and the mechanism by which Rb confers increased stability remains unclear. Here, we use1H-87Rb double resonance NMR experiments to show that FA+incorporates into the Rb-based non-perovskite phases (FAyRb1-yPb2Br5andδ-FAyRb1-yPbI3) for both bromide and iodide perovskite formulations. This is demonstrated by changes in the1H and87Rb chemical shifts,1H-87Rb heteronuclear correlation spectra, and87Rb{1H} REDOR spectra. Simulation of the REDOR dephasing curves suggests up to ~60% FA+incorporation into the inorganic Rb-based phase for the bromide system. In light of these results, we hypothesize that the substitution of FA+into the non-perovskite phase may contribute to the greater stability conferred by Rb salts in the synthesis of FA-based perovskites.

Magnetron sputtered silicon thin films for solar cell applications

One of the important directions of research in photovoltaics is the development of new thin-film technology, which can replace the currently used, more expensive bulk silicon technology. The article discusses the findings from research focused on optimizing the parameters for the deposition of silicon thin films with P-type electrical conductivity for applications in photovoltaics. The growth rate was determined depending on the change in substrate temperature using reflectometry and the influence of deposition time on optical properties was determined using UV/VIS spectroscopy. Photovoltaic structures were made on substrates with an ITO layer and their electrical parameters were measured. The authors applied the magnetron sputtering method to deposit the layers, selecting it over the commercially used the chemical vapor deposition (CVD) method. This replacement could alleviate the necessity for high temperatures and broaden the potential applications of thin-film solar cells.

Challenges and opportunities in high efficiency scalable and stable perovskite solar cells

Perovskite solar cells (PSCs) are the fastest-growing photovoltaic (PV) technology and hold great promise for the photovoltaic industry due to their low-cost fabrication and excellent efficiency. To achieve commercial readiness level, the most important factor would be yield beyond 95% at the PSC module levels. The current essential requirements for PSCs are reproducibility of high efficiency devices, scalability, and stability. The reported certified high efficiency (24–26%) results are based on the use of FAPbI3 perovskites with a bandgap of Eg≈ 1.5 eV, and the typical device's active area ranges from ≈ 0.1 cm2 to a maximum of 1 cm2. However, relatively higher bandgap PSCs are essential, especially in tandem solar cell applications. Hence, optimization of higher bandgap PSCs is a necessity. As the bandgap of the perovskites increases, the efficiency goes down due to reduced JSC and increased VOC loss. Therefore, understanding the loss mechanism and corresponding solutions need to be developed. Scaling up the device's active area without compromising the fill factor and, hence, efficiency is non-trivial. So, understanding the loss mechanism in large area devices is crucial. The stability analysis reported in the literature is inconsistent, preventing data comparison and identifying various degradation factors or failure mechanisms. Moreover, how the accelerated tests would be useful in predicting the real lifetime of the solar cells is yet to be developed. So, understanding the knowledge and the technological gaps between laboratory and industry-scale production is crucial for further development. Therefore, in this review article, we discuss the challenges and opportunities for scalable and stable high efficiency PSCs.

The Effect of Radiation on the Optical properties of TiO2 thin films as Solar Cell Application

The Effect of Radiation on the Optical properties of TiO2 thin films as Solar Cell Application

Optimization of deposition time on structural, morphological, and optical properties of Cd1-xZnxS nanocrystalline thin films

In this work, Cd1-xZnxS nanocrystalline thin films have been synthesized over a glass substrate by a simple and cost-effective Chemical Bath Deposition (CBD) technique at various deposition time keeping other deposition parameters constant. The structural, morphological, and optical properties are studied by incorporating a range of characterization techniques, including X-ray diffraction (XRD), Field Emission Scanning Electron Microscopes (FESEM), Energy Dispersive X-rays (EDX), and UV–Visible spectrophotometers (UV–Vis). The films have been deposited at five different deposition time in the range from 30 mins to 150 mins to record the changes which address in depth the structural, morphological and optical properties. Empirical fitting equations have also been developed to obtain a more quantitative analysis of the effect of deposition time. The results obtained in this work are compared with some recent reported works for performance analysis of the buffer layer. The proposed buffer layer deposited at 30 mins not only attains all the desirable qualities required for maximum extraction of solar energy but also a low-cost and environment friendly option, making it a potential candidate for solar cell and optoelectronic applications.