Solar Energy Materials and Solar Cells最新文献

The calcium looping (CaL) technique, renowned for its exceptional ability to withstand high temperatures and remarkable heat storage capacity, perfectly complements 3rd generation concentrated solar power (CSP) plants. However, the poor cycling stability and low spectrum absorption rate of CaO obstruct system efficiency. In order to tackle these problems, we impregnated steel slag with acetic acid and doped Mn to create a novel CaO-based energy storage material. Thermogravimetric analysis (TGA) and fixed-bed cycling of the material revealed that the material has outstanding cyclic heat storage properties. Compared to CaO, the material has an 85 % higher initial adsorption rate, 73 % higher 30-cycle energy storage density, and 9.5 times higher average light absorption. Spherical pellets were prepared for industrial applications through the extrusion-spheronization method. The energy storage density for 30 cycles was reduced by 10.26 % for the pellets compared to the powder material, but the average light absorption rate was improved. The compressive strength of the composite pellets was 8.4 times higher than the dolomite pellets. It was found that the light absorption capacity of the material increased with the number of cycles, which was attributed to the migration of Mn and Mg from the interior to the surface. Finally, the excellent photothermal conversion capability of the new composite material was verified by the photothermal conversion test. Therefore, Mn-doped CaO-based composite material derived from steel slag is promising for application in the next-generation CaL-CSP system.

Solar energy is widespread and easily accessible which make it the most promising renewable energy to solve energy crisis. As the ubiquitous distribution of selective solar absorbers (SSAs) employed in architecture and street, their substantially contributions to mitigate environment pollution and facilitate daily energy consumption are important; however, its implementation has been largely limited to poor color display and unideal cost-efficiency. Here, we develop a bio-inspired selective solar absorber (Bio-SSA) for use as an aesthetic compatible photothermal convector based on SiO₂/W/SiO₂/Cu resonant absorption cavity and two-dimension photonic crystal (PC), in which the solar absorption and infrared (IR) emissivity are 81.1 % and 0.17 with 7 different color display all in one. The calculated theoretically saving of year-round electricity energy up to maximum 1598 KWh when implemented in high altitude regions in China. Such Bio-SSA enjoys low-cost and simple configuration can further been utilized in large-scale and path a new way for architecture integratable solar energy system.

To improve the water production capacity of solar still (SS), realize the theoretical prediction of the enhanced SS performance, and enrich the theoretical research basis of the desalination technology of SS, this paper sets up three kinds of enhancement measures, namely, rock, corrugated plate and membrane distillation, tests the enhanced water production effect, and reveals the enhanced operation mechanism. At the same time, a performance prediction model of rock enhanced was established based on the body-centered cubic stacking rock technology, and the influence of rock parameters on the distillation effect was studied. The study found that the water production increment of the three enhancement measures was concentrated in the rising period of the water production of the SS, and the total water production was 6.38 %, 12.30 % and 11.63 % higher than that of the traditional basin SS, respectively. The rock or corrugated plate enhances the distillation effect by elevating the seawater temperature and its temperature difference with the cover plate, and the membrane distillation increases the total water production through the additional water production of the membrane. Moreover, the constructed model can effectively predict the characteristics of rock enhanced SS. The increase in the rock layer thickness and the decrease in the rock particle size and material heat capacity both enhance the total daily water production, but the effect of rock particle size and material is weak. Although the increase of thickness increases the water production obviously, it aggravates the fluctuation of water production.

The reflection behavior of an Ag deposition-based reversible electrochemical mirror is determined by the morphology of the electrodeposited Ag. This study demonstrates the control of the morphology of Ag deposits through the modulation of the electrolysis conditions, specifically the applied potential and Ag⁺ ions concentration, without increasing the amount of Ag deposits. By applying a potential with a sufficiently large deposition overpotential for continuous deposition on the electrode surface, the deposited Ag formed a flat surface, resulting in high reflectivity. Considering the concentration dependence of Ag⁺ ions, the diffusion of Ag⁺ ions to the electrode significantly affected the resulting morphology of the deposits. At higher Ag⁺ concentrations, the time for the transition to a diffusion-limited process increased because Ag⁺ ions were close to the working electrode. Therefore, a flat Ag layer was obtained due to the promotion of three-dimensional deposition, including the in-plane growth.

MgCl₂–NaCl–KCl (MgNaK) eutectic salt has emerged as a highly promising candidate for concentrated solar power (CSP), with extensive research conducted in recent years. However, the thermal property data for the MgNaK eutectic salt are still very limited. Here, we present a novel and accurate many-body potential trained by machine learning (ML) for MgNaK eutectic salt (with mole fractions of 45.4 %, 33 %, and 21.6 % respectively), developed using energies and forces extracted from first-principles molecular dynamics calculations (FPMD). The performance of the potential is well tested. We conduct a detailed investigation on the temperature-dependent structural and corresponding thermal properties, analyzing them from both the atomic and electronic perspectives. The introduction of Na⁺ or K⁺ ions disrupts the net structure formed by corner-joint and edge-joint MgCl_x units, thereby affecting the transport properties. The calculated density (ρ) and constant pressure specific heat capacity (C_P) exhibit agreement with experimental data within a margin of 2 %. We observe and discuss the typical λ of negative linear temperature correlation, which is similar to other molten alkali chloride salts. Finally, based on the simulated and experimental values, we provide reliable recommendations for the λ and viscosities (η) of MgNaK eutectic salt across its entire operating temperature range.

This work sheds light on the potential of Cadmium Selenide (CdSe) solar cells for indoor applications. CdSe boasts a wide direct bandgap, high carrier mobility, and a high absorption coefficient, making it an attractive candidate for harnessing ambient indoor light. Our study centers around an experimental solar cell architecture composed of FTO/CdSe/PEDOT:PSS/CuI/ITO, which exhibits a power conversion efficiency (PCE) of 6.00 %. Through a meticulous analysis of the core technological aspects of this cell, we successfully replicate the measured current-voltage characteristics and other experimental data, affirming the validity of our simulation modeling approach. Moving forward, we delve into the design and optimization of CdSe-based solar cells under white LED illumination. We emphasize the pivotal role of a double-hole transport layer (HTL) configuration over a single HTL, with a focus on optimizing the alignment between the HTL/back contact and HTL/absorber interfaces. The strategic incorporation of a heavily doped p-type HTL material, boasting both a deep valence band maximum (VBM) and a shallow conduction band minimum (CBM), is identified as paramount, especially for a deep VBM absorber like CdSe. Adding double HTL materials also facilitates efficient hole collection within the CdSe thin film while mitigating undesirable electron-hole recombination at the critical interface between the hole collection layer and the electrode. The implementation of a double HTL configuration based on CuI/ZnTe:Cu or CuI/BCS significantly enhances performance, resulting in a PCE in the order of 20 % under 200 lux and 2900 K LED illumination. Moreover, we introduce the single HTL design to provide other alternatives for efficiency boosting. Upon increasing the work function of the front contact, it is found that the valence band offset between the HTL and the absorber can be engineered, resulting in a PCE above 21.5 %.

Magnetized wood (M–W) has been proposed to be used as an absorber in solar-driven interfacial evaporation. The M−W could gain an evaporation rate of 1.46 kg m⁻² h⁻¹ under the combined effect of sunlight and magnetic fields, which is 27 % higher than carbonized wood (C–W). To explore the mechanism, they were subjected to SEM, XPS, and water contact angle tests. It is revealing that M−W forms much more microchannels for steam diffusion. The M−W shows 97 % optical absorption within the whole wavelength, while the C–W is lower than 85 %, revealing the M−W can gather most of the solar radiation. Finally, the permeability coefficients of carbonized and magnetized woods are calculated by the CFD model. The permeability coefficient of the M−W is 20 % higher than the C–W, which can be attributed to Fe₃O₄ nanoparticles disturbing the steam growth in the magnetic field, hence decreasing the thickness of the liquid film covering the bubbles and improving the solar evaporation rate.

The current progress in tower-based solar thermal concentrators and receivers enables achieving temperatures within the required range of 500–700 °C for the S–CO₂ Brayton cycle. Within this temperature range, the efficiency of the S–CO₂ Brayton cycle exceeds that of conventional steam power cycles. This study applies the S–CO₂ Brayton cycle to concentrated power generation systems, emphasizing structural and parameter optimization. By utilizing the operational parameters of tower-based solar thermal power generation as boundary conditions and maximizing specific power as the optimization objective, various configurations derived from a maximum of two fundamental cycles are systematically enumerated. Subsequently, an intelligent algorithm optimizes the power cycle flow and parameters for each structure, further optimizing the heat exchanger network. The findings reveal that the optimized configuration shares a common heating and cooling process. This optimization yields a specific power increase of 14.62 kJ/kg compared to the reference case, indicating a 13.26 % enhancement. Additionally, the cycle efficiency improves to 47.45 %, marking a 28.52 % increase. The overall system efficiency for the solar power tower system reaches 32.03 %, with an exergy efficiency of 32.19 %.

Fatty acid phase change emulsions possess the combined properties of heat transfer fluids and phase change materials, making them suitable for applications in the energy industries. This study aims to develop aqueous phase change emulsions using stearic acid as the heat storage medium. Stable nanoemulsions with an average droplet size of 100 nm and various stearic acid weight fractions were successfully prepared. Melting enthalpy up to 42.06 kJ/kg was achieved. The nanoemulsions exhibited good stability under conditions of storage and 300 freezing/melting cycles. Furthermore, when a 6 wt% ratio of nanoparticles boron nitride (BN) was added to the emulsion containing 20 wt% dispersed phase, the thermal conductivity increased by 15.7 %, and the supercooling degree reduced by 57.1 % compared to the original emulsion, while the emulsion demonstrated good dispersion stability.

Developing smart textiles based on phase change materials (PCMs) enables dynamic regulation of personal thermal management through the absorption and release of latent heat. Integrating synchronous thermal management of PCMs, solar heating, and Joule heating allow for the design of textiles that can adapt to various climate environments, significantly extending their utility and application range. Herein, a fiber membrane based on microencapsulated PCMs (MPCM) and uniaxial electrospinning was prepared. Microencapsulation technology effectively prevent the leakage of PCMs. Ag nanoparticles were grown in-situ on the surface of MPCM (APCM) before spinning to improve the thermal and electrical conductivity of MPCM. By employing the electrospinning method, APCM was wrapped within a PVDF fiber network, effectively preventing its displacement or detachment during use, with ideal heat enthalpy (90.34 J/g, at a mass ratio of APCM to fiber of 60 wt%). Following continuous modification by polydopamine (PDA) and polypyrrole (PPy), the composite fiber membrane (PAPP-6) exhibits both photothermal and electrothermal conversion capabilities. Due to the synergistic effect of PDA and PPy, the surface peak temperature of PAPP-6 reached 57.5 °C (100 mW/cm²). The introduction of PPy enhances the conductivity of PAPP-6, resulting in a surface peak temperature of 42.7 °C (5.0 V). The desirable heat storage capacity of PAPP-6 fiber membrane, combined with the benefits of functional integration, well mechanical property, makes it an excellent candidate for personal thermal management.