Solar Devices Research Articles

Efficient Solar-Driven Interfacial Water Evaporator using Hydrogel Modified Carbon-Based Biomass with Abundant Microchannels.

The conventional sea water desalination technologies are not yet adopted worldwide, especially in the third world countries due to their high capital cost as well as large energy requirement. To solve this issue in a sustainable way an interfacial solar water evaporation device is designed and proposed in this article using the branches of Prunus serrulata (PB). The PB has abundant microchannels and shows excellent photothermal conversion capability after carbonization. Moreover, the easy access to raw materials and the facile fabrication process makes the solar water evaporating device very cost effective for seawater desalination application. Experiments show that in the presence of the fabricated evaporator the evaporation rate of water can reach 3.5kgm-2h-1 under 1 sun, which is superior to many similar experimental devices. In addition, its advantages, such as effective sewage purification capability, low cost, and environmental friendliness, make this evaporator highly competitive in the extensive promotion of this technology and can be considered as a new sustainable solution for seawater desalination with great application potential and prospects.

Design and optimization of a high efficiency CdTe–FeSi2 based double-junction two-terminal tandem solar cell

This article theoretically demonstrates an enormously efficient CdTe–FeSi2 based dual-junction tandem solar cell accompanied by slender semiconductor layers. The peak efficiency of the device has been ensured through the optimization of its various attributes of window, CdTe (bandgap 1.5 eV) top absorber, FeSi2 (bandgap 0.87 eV) bottom absorber and back surface layers. Additionally, the impacts of thickness, doping and the level of defects in different window, base and rear surface layers have been examined to observe how different layers affect the solar cell's performance. The optimized n-CdS/p-CdTe/p+-MoS2--n-CdS/p-FeSi2/p+-Cu2SnS3 dual-junction tandem solar device displays an efficiency of 43.9% with a voltage at no load, VOC of 1.928 V, current density under a closed circuit, JSC of 25.34 mA/cm2, and fill factor of 89.88%, respectively. These results disclose the high potential of the suggested solar cell based on CdTe and FeSi2 compounds.

Enhancing grain growth of caesium-formamidinium-based lead halide perovskite thin films through PbI2 precursor engineering in vapor-solid reaction

Vapor-solid reaction methods are highly regarded as potential solutions for large-scale production of perovskite thin films due to their scalability, compatibility with silicon tandem technology, and lack of solvents. However, the limited penetration of organic vapor through the solid inorganic film results in a slow growth rate of perovskite, leading to poor crystallinity and small grain size. This high defect density in the grain boundaries hinders the enhancement of device performance. In this study, we used 1,3-diaminoguanidine monohydrochloride as an additive in the PbI2 precursor films, which effectively improved perovskite grain growth in the vapor-solid reaction process. After optimization, we achieved high-quality perovskite thin films with a large grain size exceeding 5 μm. Notably, solar devices based on these large-grain perovskite thin films achieved a high power conversion efficiency up to 21.13%.

Ion-engineered solar desalination: Enhancing salt resistance and activated water yield

Solar desalination, which relies on localized heating for interfacial water evaporation, is regarded as a promising and sustainable approach for freshwater production. Significant progress has been achieved in developing high-performance solar-driven interfacial vapor generators (SIVGs), however, their performance in high-concentration brine remains unsatisfactory. Herein, a novel SIVG is proposed as a candidate with advanced ionization engineering design for solar desalination, which exhibits enhanced desalination performance. The design of ionization engineering can promote salt-blocking effects through electrostatic attraction between salt ions in seawater and polymer chains of hydrogel-based evaporator, and high-continuity porous structures, which also contributes to a high evaporation performance by increasing the production of activated water molecules. Furthermore, the introduction of CuO nanoparticles with excellent localized surface plasmon resonance effect enables the light-absorbing copper-based hydrogel (LACH) to achieve an impressive sunlight absorptance rate of 95 %. The evaporation rate and energy efficiency of LACH reach a remarkable 3.93 kg·m−2·h−1 and 93.5 % in simulated brine (3.5 wt% NaCl solution) under one-sun illumination. The salt-resistant LACH-related SIVG is one of ideal candidates for sustainable freshwater harvesting over extended periods. This study is expected to offer valuable insights for advancing the research and development of next-generation solar desalination devices.

Ultra-broadband and wide-angle plasmonic light absorber based on all-dielectric gallium arsenide (GaAs) metasurface in visible and near-infrared region

High-performance and cost-effective broadband light absorbers are crucial for various optical applications, including solar energy harvesting, thermophotovoltaic systems, and integrated photoelectric devices. In this study, an ultra-broadband and wide-angle plasmonic light absorber (PLA) based on an all-dielectric gallium arsenide (GaAs) metasurface in the visible and near-infrared regions is proposed and numerically investigated. The unit-cell of the proposed PLA is consisted of all-dielectric GaAs cylinder resonator (CR) adhered on an ultra-thin GaAs spacer layer backed with a tungsten (W) substrate. Numerical simulation results show that the absorption peak of the proposed PLA is up to 99.85 %, 99.9 % and 99.98 % at 0.452 μm, 0.712 μm and 1.596 μm, respectively. In addition, the ultra-broadband strong absorption of over 90 % also can be achieved from 0.39 μm to 2.09 μm with a relative bandwidth of 137.1 %. The ultrabroadband strong absorption of the proposed PLA is further demonstrated by the equivalent circuit model (ECM), which displays excellent agreement with the results of the full-wave numerical simulation performed using the finite element method (FEM). The simulated electromagnetic (EM) field distributions reveal that the ultra-broadband strong absorption of the designed PLA is mainly from the excited propagating surface plasmon (PSP), located surface plasmon (LSP), cavity resonance modes combined with coupling effect between adjacent CRs. The proposed PLA is also polarization-insensitive and wide incident angles for both transverse electric (TE) and transverse magnetic (TM) modes. The absorption properties of the designed PLA can be adjusted by varying geometric parameters of the unit-cell. The PLA achieves a remarkable short-circuit current density of over 64.75569 mA/cm2 and exhibits nearly perfect solar energy trapping due to the effective coupling of multiple resonances, resulting in enhanced photovoltaic performance. Thus, the proposed PLA can be potential application in the photodetectors, thermal imaging, and solar energy harvesting devices.

Solid waste-derived solar desalination devices: Enhanced efficiency in water vapor generation and diffusion

Water scarcity and waste pollution are serious global challenges due to the rapid development of the global economy and population growth. A win–win strategy to address the water crisis and reduce pollution is to use waste materials as low-carbon and eco-friendly photothermal materials for solar-driven desalination. Steel slag, an abundant industrial waste product, has excellent thermal conductivity. Enhancing its light absorption and hydrophilicity could enable the creation of efficient and economical solar seawater desalination devices. In this study, our research introduces a 3D desalination device using this modified slag, achieving a consistent evaporation rate fluctuating around 29 kg m-2h−1 at 4 m s−1 wind speed for five days. This breakthrough can be attributed to the excellent light-to-heat conversion of the modified steel slag, coupled with the synergistic interaction between the porous evaporator and wind, culminating in efficient steam evaporation and diffusion. Life Cycle Analysis (LCA) reveals that the carbon emissions of the modified steel slag for desalinating each ton of seawater are only 2.20 kg CO2-eq, indicating superior prospects for carbon reduction compared to the reverse osmosis (RO) and Multi-Stage Flash Desalination (MSF) processes.

On Numerical Modelling and an Experimental Approach to Heterojunction Tandem Solar Cells Based on Si and Cu2O/ZnO—Results and Perspectives

A comparative analysis of three advanced architectures for tandem solar cells (SCs) is discussed, respectively: metal oxide, thin film, and perovskite. Plasmonic solar cells could further increase solar cell efficiency. Using this development, an innovative PV technology (an SHTSC based on metal oxides) represented by a four-terminal Cu2O/c-Si tandem heterojunction solar cell is investigated. The experimental and numerical modelling study defines the main aim of this paper. The experimental approach to SHTSCs is analysed: (1) a Cu2O layer is deposited using a magnetron sputtering system; (2) the morphological and optical characterization of Cu2O thin films is studied. The electrical modelling of silicon heterojunction tandem solar cells (SHTSCs) is discussed based on five simulation tools for the optimized performance evaluation of solar devices. The main novelty of this paper is represented by the following results: (1) the analysis suggests that the incorporation of a buffer layer can improve the performance of a tandem heterojunction solar cell; (2) the effect of interface defects on the electrical characteristics of the AZO/Cu2O heterojunction is discussed; (3) the stability of SHTSCs based on metal oxides is studied to highlight the degradation rate in order to define a reliable solar device. Perspectives on SHTSCs based on metal oxides, as well as Si perovskite tandem solar cells with metal oxides as carrier-selective contacts, are commented on.

Effect of phase distribution and defect passivation on amplified spontaneous emission of quasi-2D Dion–Jacobson perovskite

Quasi-2D Dion–Jacobson (DJ) halide perovskites with large exciton binding energy, self-assembled quantum wells, and high quantum yield attract growing attention in light-emitting diodes and solar devices. DJ-layered perovskites have the eliminated van der Waals gap and show improved photophysical features. However, there are a variety of defects and complex phase distributions produced during the solution procedure and the fast crystal development. In this paper, we reveal the effect of phase distribution and defect passivation on amplified spontaneous emission of quasi-2D perovskite (PDMA)(MA)2Pb3Br10 thin films through solvent engineering and additive methods, by establishing the correlation between the precursor compositions and the photophysical performance of the layered DJ perovskites. The energy transfer rate and the photoluminescence quantum yield increase due to the spatially homogeneous domain distribution and the reduced defect density after the addition of KBr in the DMSO:DMF. More importantly, we realize green amplified spontaneous emission and single-mode vertical-cavity surface-emitting lasing with low thresholds of 8.8 and 10.5 μJ cm−2, respectively. This work provides a guideline to achieve low-threshold multicolor lasers based on DJ perovskites.

Comparative Thermal Insulation Nature of Ca2FeMnO6−δ and Sr2FeMnO6−δ

In this study, we investigate the utility of Ca2FeMnO6-δ and Sr2FeMnO6-δ as materials with low thermal conductivity, finding potential applications in thermoelectrics, electronics, solar devices, and gas turbines for land and aerospace use. These compounds, characterized as oxygen-deficient perovskites, feature distinct vacancy arrangements. Ca2FeMnO6-δ adopts a brownmillerite-type orthorhombic structure with ordered vacancy arrangement, while Sr2FeMnO6-δ adopts a perovskite cubic structure with disordered vacancy distribution. Notably, both compounds exhibit remarkably low thermal conductivity, measuring below 0.50 Wm−1K−1. This places them among the materials with the lowest thermal conductivity reported for perovskites. The observed low thermal conductivity is attributed to oxygen vacancies and phonon scattering. Interestingly as SEM images show the smaller grain size, our findings suggest that creating vacancies and lowering the grain size or increasing the grain boundaries play a crucial role in achieving such low thermal conductivity values. This characteristic enhances the potential of these materials for applications where efficient heat dissipation, safety, and equipment longevity are paramount.

Pseudo-photoelectric cascade conversion endowing photosensitive Janus ionogel for solar energy harvesting and sensing

Ionic conductive gel based self-powered sensor has attracted much attention in Internet of Things era, due to its softness, versatility, electrical conductivity, iontronics and responsiveness. However, its multi-scene application is limited by few types of these perceptible signals. Herein, a photosensitive Janus ionogel with pseudo-photoelectric effect based on cascade conversion is reported, with seebeck coeffect of 19.5 mV K−1 and ZT value of 0.63. Significantly, the photosensitive Janus ionogel can generate different temperature gradients on the different intensity of sunlight, and convert solar energy into electric energy by the “light-thermal-electric” cascade conversion, demonstrating its great potential in solar energy utilization and light sensing. This investigation paves a promising and versatile way to construct photosensitive conductive materials for next-generation solar self-powered devices.

Optimization of Stable Energy PV Systems Using the Internet of Things (IoT)

The modern power grid faces rapid growth in load demand due to industrialization, leading to an unregulated environment and increasing adoption of renewable energy sources, which presents technical challenges, particularly in terms of stability. Hydrogen conversion technology revolutionizes clean electricity storage with renewable energy, and solar hydrogen is now available in autonomous solar systems. The efficiency of solar photovoltaic systems is closely related to using digital electronic maximum peak power tracking (MPPT) technology. The Internet of Things (IoT) is crucial for performance monitoring and real-time control of PV systems, enhancing the understanding of real-time operating parameters. IoT and wireless sensor networks for distributed solar energy devices and joint building design are essential for developing the photovoltaic construction industry. In this paper, the monitoring system that has been proposed offers a potentially effective solution for the intelligent remote and real-time monitoring of solar photovoltaic (PV) systems. It demonstrated a high level of accuracy, reaching 98.49%, and can transmit graphical representations to a smartphone application within a time frame of 52.34 seconds. Consequently, the battery's longevity was extended, energy consumption was diminished, and the quality of service (QoS) for real-time applications inside the Internet of Things (IoT) was enhanced.

Development of electrostatic removal system for application in dust removal from Martian spacesuits

Dust removal from Martian spacesuits whilst on exploration activities is critically important for long-term Martian exploration missions. Martian dust is known to contain harmful particles which must be removed from Martian spacesuits to prevent entry into habitation zones on Mars, and prevent spacesuit wear. In this work, an Electrostatic Removal System was developed which utilised the phenomenon of dielectrophoresis to remove Martian dust from the outer layer of spacesuits. Dielectrophoretic forces were exerted on dust particles by an alternating electrostatic field which acted to remove the particles from a surface. The field was generated by applying high voltage square waves, produced by a MOSFET H-Bridge, across an array of parallel copper electrodes contained within an Electrostatic Removal Device. A theoretical model was derived to predict the effect of variables on the system performance, which was validated through experimental testing. This system demonstrated a high dust clearing performance of over 95% when the dust is in direct contact with the Electrostatic Removal Device’s surface. However, the system was not able to achieve dust removal from samples of Nomex, Teflon, and Kevlar, the three constituent materials of the outer layer of spacesuits. Further development is required for the system to become a viable option for the removal of Martian dust from spacesuits. Nonetheless, this system may prove effective in other applications such as dust removal from solar panels or optical devices, where the electrodes may be able to be integrated directly beneath the dust layer.

Highly Efficient Inverted Light-Emitting Diodes Based on Vertically Aligned CdSe/CdS Nanorod Layers Fabricated by Electrophoretic Deposition.

Inverted colloidal-nanocrystal-based LEDs (NC-LEDs) are highly interesting and invaluable for large-scale display technology and flexible electronics. Semiconductor nanorods (NRs), in addition to the tunable wavelengths of the emitted light (achieved, for example, by the variation of the NR diameter or the diameter of core in a core-shell configuration), also exhibit linearly polarized emission, a larger Stokes shift, faster radiative decay, and slower bleaching kinetics than quantum dots (QDs). Despite these advantages, it is difficult to achieve void-free active NR layers using simple spin-coating techniques. Herein, we employ electrophoretic deposition (EPD) to make closely packed, vertically aligned CdSe/CdS core/shell nanorods (NRs) as the emissive layer. Following an inverted architecture, the device fabricated yields an external quantum efficiency (EQE) of 6.3% and a maximum luminance of 4320 cd/m2 at 11 V. This good performance can be attributed to the vertically aligned NR layer, enhancing the charge transport by reducing the resistance of carrier passage, which is supported by our finite element simulations. To the best of our knowledge, this is the first time vertically aligned NR layers made by EPD have been reported for the fabrication of NC-LEDs and the device performance is one of the best for inverted red NR-LEDs. The findings presented in this work bring forth a simple and effective technique for making vertically aligned NRs, and the mechanism behind the NR-LED device with enhanced performance using these NRs is illustrated. This technique may prove useful to the development of a vast class of nanocrystal-based optoelectronics, including solar cells and laser devices.

Waste Tea-Derived Theabrownins for Solar-Driven Steam Generation.

Solar-driven seawater desalination has been considered an effective and sustainable solution to mitigate the global freshwater crisis. However, the substantial cost associated with photothermal materials for evaporator fabrication still hinders large-scale manufacturing for practical applications. Herein, we successfully obtained high yields of theabrownins (TB), which were oxidation polymerization products of polyphenols from waste and inferior tea leaves using a liquid-state fermentation strategy. Subsequently, a series of photothermal complexes were prepared based on the metal-phenolic networks assembled from TB and metal ions (Fe(III), Cu(II), Ni(II), and Zn(II)). Also, the screened TB@Fe(III) complexes were directly coated on a hydrophilic poly(vinylidene fluoride) (PVDF) membrane to construct the solar evaporation device (TB@Fe(III)@PVDF), which not only demonstrated superior light absorption property and notable hydrophilicity but also achieved a high water evaporation rate of 1.59 kg m-2 h-1 and a steam generation efficiency of 90% under 1 sun irradiation. More importantly, its long-term stability and exceptionally low production cost enabled an important step toward the possibility of large-scale practical applications. We believe that this study holds the potential to pave the way for the development of sustainable and cost-effective photothermal materials, offering new avenues for utilization of agriculture resource waste and solar-driven water remediation.

Heat-sink-free solar-driven thermoelectric device for micro energy scavenging

Harvesting energy from nature, such as mechanical energy, thermal energy, and biomass energy, has become an effective way to supply power for self-driven sensing and Internet of Things (IoT) applications. Among that, solar-driven thermoelectric (STE) device takes advantage of all-solid-state energy conversion, such as no noise, easy access, and free of wear, exhibiting great potential. Here, we propose a solar-driven thermoelectric device for harvesting solar energy, based on Micro Electromechanical System (MEMS) technology. Specifically, the optimization of solar absorptances of structural layers significantly improved the photo-thermo-electric conversion performance. Furthermore, the electrical output strongly depends on temperature difference dominated by the absorptance difference. Therefore, the reported device can be free of traditional heat sink, which greatly simplifies its structure and expands the working conditions, especially in microdevices. Particularly, a continuous output voltage of 0.34 V/cm2 is achieved with concentrated solar radiation, demonstrating its potential under no heat sink conditions. Besides, a fast response (4.2 ms under 660 nm laser) is achieved benefitting from the micron-size solar absorber, showing its significance in sensing applications. Finally, the proposed STE device is utilized to harvest outdoor solar energy, displaying promising potential in solar energy harvesting devices and providing an insightful perspective for thermoelectric applications.

Solar Hybrid System: Innovations in Cooking, Drying, and Power Generation

A hybrid system has been designed and developed which comprises the principle of solar thermal and photovoltaic. Flat plate collector and concentrating trough collector were incorporated under solar thermal technology. Solar thermal device which makes the most using infrared radiation out of solar spectrum. Black copper sheet at focal point of the solar trough served as a stand for cooking pan was able to gain direct as well as high intensity reflected solar radiation to expedite the cooking process. The electric unit of the system worked on the principle of photovoltaic effect. Main components of the hybrid system were collector housing, solar trough reflector, triangular shaped glazing surfaces, copper sheet to place cooking pots and dedicated insulation to prevent heat loss. The dual concept hybrid system was found exceptionally speedier as compared to traditional box type cooker. Results revealed that cooking pot attained maximum temperature of 104.50 C at 12.30 pm, which was sufficient for cooking nutritious food. The experiment was conducted in winter season on 18th January, 2018. Average thermal efficiency (ηtherm) was estimated as 35.1%, cooking power (P) was estimated 47.68 W and the overall heat loss coefficient was calculated 3.03 W/m2°C. Average cooking time found to be just 130 minutes which was otherwise more than 3 hrs in case of traditional box type cooker. Electric power which was stored in the battery can operate 5W dc bulb for 9 hours in single charging. It also could operate smart phone charger and a dc fan (12V, 4Ah) for 60 minutes each.

A novel soft sensing method using intelligent modeling method for solar irradiance and temperature in distributed PV power plant

AbstractDistributed photovoltaic (PV) power plants often lack solar irradiance monitoring devices, significantly hindering crucial functions such as power forecasting, fault diagnosis, and performance calculation for distributed PV. To address this issue, a real‐time method for soft sensing solar irradiance was proposed in distributed PV. First, we investigated the typical relationship between solar irradiance, ambient temperature, and the electrical characteristics of PV cells. Based on this relationship, we utilized the small sample modeling technique of the Genetic Algorithm‐Support Vector Machine to calculate the ambient temperature. Subsequently, a solar irradiance calculation model based on the backpropagation neural network was developed, taking the PV array voltage, current, calculated ambient temperature, and power as inputs. This approach enables for the estimation of solar irradiance in distributed PV power plants through a simple and efficient calculation process. To demonstrate the reliability and flexibility of the algorithm, we conducted testing with data under various input conditions, such as different power plant configurations, and seasons, coefficient of determination for the proposed model reached 0.95. Overall, the novelty of the proposed method offers a practical solution for soft sensing of solar irradiance in PV power plants, enabling accurate performance analysis and effective operation management without hardware investment.

Cu-Doped Sb2Se3 Thin-Film Solar Cells Based on Hybrid Pulsed Electron Deposition/Radio Frequency Magnetron Sputtering Growth Techniques

In recent years, research attention has increasingly focused on thin-film photovoltaics utilizing Sb2Se3 as an ideal absorber layer. This compound is favored due to its abundance, non-toxic nature, long-term stability, and the potential to employ various cost-effective and scalable vapor deposition (PVD) routes. On the other hand, improving passivation, surface treatment and p-type carrier concentration is essential for developing high-performance and commercially viable Sb2Se3 solar cells. In this study, Cu-doped Sb2Se3 solar devices were fabricated using two distinct PVD techniques, pulsed electron deposition (PED) and radio frequency magnetron sputtering (RFMS). Furthermore, 5%Cu:Sb2Se3 films grown via PED exhibited high open-circuit voltages (VOC) of around 400 mV but very low short-circuit current densities (JSC). Conversely, RFMS-grown Sb2Se3 films resulted in low VOC values of around 300 mV and higher JSC. To enhance the photocurrent, we employed strategies involving a thin NaF layer to introduce controlled local doping at the back interface and a bilayer p-doped region grown sequentially using PED and RFMS. The optimized Sb2Se3 bilayer solar cell achieved a maximum efficiency of 5.25%.

HTL-free non-toxic perovskite tandem solar device MAGeI3/FASnI3 with 25.69% efficiency: design and simulation using SCAPS

HTL-free non-toxic perovskite tandem solar device MAGeI3/FASnI3 with 25.69% efficiency: design and simulation using SCAPS

Black kitchen waste based solar evaporator employing radiative cooling film as difffuse substrate for efficient desalination

Many substances looks black often means that these substance can completely absorb ultraviolet radiation and Visible incident light (UV). Ultraviolet and visible light account for 57 % of the incident energy of the sun. There are many substances that looks black, but have not been paid attention in the field of photothermal interface evaporation. Based on the above discussion, this paper selects the waste black round plastic lunch box and a piece of black garbage bag as solar photothermal materials to make a solar desalination device, and proves that these black garbage can be recycled and reused to make an interface solar evaporator. In this paper, a 2D desalination device with photothermal interface evaporation for solar thermal conversion was successfully fabricated using only black round plastic lunch box as photothermal material and polyester cloth as water delivery channel. In addition, a black garbage plastic bag as the only solar photothermal conversion material has also been reused in the preparation of 3D evaporators. Using the radiation cooling film as the diffuse reflection substrate, the 3D device makes the incident sunlight reflected from the radiation cooling film and polyester cloth to the black garbage plastic bag many times, making the whole evaporation device. It can reabsorb solar incident light many times. After testing, the solar energy absorption rate of the 3D evaporator is as high as 96.6 %, and the steam output is as high as 8.96 kg m−2 h−1.