Materials for Renewable and Sustainable Energy最新文献

Solar radiation offers benefits such as sustainability, renewability, and environmental friendliness. Furthermore, solar energy can generate multiple forms of energy. Over the past 30 years, the use of dye-sensitized solar cells (DSSCs) has been extensively investigated due to their simple manufacturing process, low cost, and excellent energy conversion and storage capabilities. In this work, a DSSC was fabricated with a poly(ethyl methacrylate) (PEMA) polymer electrolyte impregnated with an iodide-based ionic liquid. The influence of the ionic liquid on the interfacial characteristics and overall efficiency of the DSSCs with this polymer electrolyte was examined. The ionic liquid-doped polymer electrolyte exhibits an ionic conductivity of 1.27 × 10⁻⁴ S/cm at 40 wt% at room temperature. The DSSC has a conversion efficiency of 1.47% under one-sun conditions. The incorporation of the ionic liquid demonstrated improved stability and efficiency in photovoltaic power generation.

The increasing demand for sustainable energy solutions has led to extensive research on thermoelectric materials that convert waste heat into electricity. Half-Heusler alloys are promising candidates due to their stability, electronic properties, and moderate thermal conductivity. To assess their thermoelectric potential, this study investigates the structural, electronic, mechanical, and thermoelectric properties of XRhP (X = Ti, Zr, Hf) alloys. Density Functional Theory (DFT) calculations using the WIEN2k software were employed to study structural, electronic, and mechanical properties. The BoltzTraP code was used to compute transport properties such as the Seebeck coefficient (S), electrical conductivity (σ), and thermal conductivity (κ). The Slack model estimated lattice thermal conductivity (κ_L), and the thermoelectric figure of merit (zT) was calculated. The optimized lattice parameters for TiRhP, ZrRhP, and HfRhP were 5.75 Å, 5.98 Å, and 5.95 Å, respectively. These alloys exhibit semiconducting behavior with band gaps of 0.85 eV, 1.44 eV, and 0.73 eV. At 1400 K, the highest zT values were 1.31, 0.70, and 1.46, with reduced lattice thermal conductivities of 0.52 W/m·K, 0.43 W/m·K, and 0.40 W/m·K, respectively, in the p-type material of XRhP alloy, highlighting their potential for thermoelectric applications.

CeO₂ nanorod photocatalysts with systematically tuned oxygen vacancy concentrations were synthesized via a one-step NaBH₄-assisted hydrothermal method to elucidate the role of defect engineering in photocatalytic water splitting. A series of reduced samples (Ce1–Ce5) and pristine CeO₂ were thoroughly characterized. Increasing NaBH₄ dosage induced XRD peak broadening with crystallite size reduction (5.37–4.44 nm) and a UV–Vis DRS red shift with bandgap narrowing (2.89–2.72 eV). Urbach energy increased (0.36–0.41 eV), reflecting mid-gap state formation. Raman, FTIR, and EPR (g ≈ 2.002) confirmed rising oxygen vacancy and Ce³⁺ content, consistent with XPS, which revealed enhanced oxygen vacancy-related O 1s contribution (16.7–43%) and Ce³⁺ fraction. Valence-band XPS and secondary electron cut-off showed band-edge shifts and reduced work function, promoting charge transfer. PL and TCSPC indicated prolonged carrier lifetimes in Ce3 (τ_i − τ_a = 1.1087 ns), while Ce4–Ce5 exhibited deep traps. CDB and S-parameter analyses identified Ce3 as optimal, balancing shallow and deep traps for efficient carrier dynamics. BET and BJH confirmed Ce3’s highest surface area (~ 1465 m²/g) and mesoporosity. Morphological analysis showed smooth rods (Ce, Ce1) evolving to porous, defect-rich rods (Ce2–Ce3) and partial amorphization (Ce4–Ce5). Ce3 delivered the highest H₂ evolution under visible light without sacrificial agents, highlighting the critical role of controlled oxygen vacancy engineering in advancing CeO₂-based solar hydrogen production.

Optimal electrode formulations were developed for anionic exchange membrane electrolysis cells. These included improved platinum-group metals (PGMs) free cathodic NiMo and anodic NiFe-oxide-hydroxide (Layered Double Hydroxide, LDH)-based electrocatalysts. The synthesis of the electrocatalysts was performed using simple and cost-effective co-precipitation methods. The characterization of the electrocatalysts included an analysis of their physico-chemical properties with regard to the crystallite size and active phase dispersion. The optimal ionomer dispersion casted for the catalytic ink was investigated. The assessment of the improved electrodes was carried out in single cell in the presence of an AEM hydrocarbon FumaTech® membrane. Despite the reduced crystallite size in supported NiMo alloy electrocatalysts, their performance was affected by lower catalytic activity and higher activation control with respect to unsupported NiMo electrocatalysts. Three different ionomers’ contents were investigated (33 wt. %, 20 wt. % and 10 wt. %) to individuate the most promising electrode formulations for the AEM electrolysis. A 10 wt. % of ionomer content in the electrode showed the best performance for unsupported anode and cathode electrocatalysts. This optimal ionomer concentration appeared related to the enhanced gas permeability of the catalytic layers while assuring appropriate binding characteristics. The achieved performance was comparable or better than the best results observed in the literature under similar operating conditions showing more than 2 A cm⁻² at 2 V/cell after 100 h operation for a PGM-free AEM water electrolysis cell. The optimized configuration showed promising characteristics for further development and upscaling for large scale AEM water electrolysis applications.

Nanostructured metal hydrides have garnered interest in their potential to store hydrogen safely and effectively as an energy carrier. By partially substituting lanthanum (La) with cerium (Ce), the structure of lanthanum pentanickel (LaNi₅) was maintained to create a novel encapsulated La–Ce–Ni-based metal hydride (La_0.6Ce_0.4Ni₅). The incorporation of metal-polymer composites can protect metal hydrides from oxidation and enhance cyclic stability. Carbon-based materials such as graphene and multi-walled carbon nanotubes (MWCNTs) not only store hydrogen but also improve the reaction kinetics and address thermal management issues. This study presents La_0.6Ce_0.4Ni₅ composites using porous polymers—polymethyl methacrylate (PMMA) and polyvinylidene fluoride (PVDF) and carbon-based materials (graphene, MWCNTs) synthesized via a solvent-based method. The aim is to enhance hydrogen storage kinetics and stability. The composite’s thermal stability was analyzed using differential scanning calorimetry, and its structural phase composition was examined through X-ray diffraction. Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) were employed to qualitatively estimate the surface functional groups. Hydrogen storage kinetics were measured using temperature-programmed desorption in a Sieverts-type apparatus. The creation of surface functional groups on La_0.6Ce_0.4Ni₅ improved the dispersion of the polymer and carbon particles. Hydrogen storage kinetics were evaluated through dehydrogenation (DHH) experiments in a Sieverts-type apparatus. The composite, consisting of La_0.6Ce_0.4Ni₅ with 8% PMMA and 8% MWCNTs can store 0.8 wt% H₂ at room temperature and pressure in under 20 min with good stability over three cycles, while the hydrogenation (HH) at 5 bar pressure can store 1.05 wt% of hydrogen in less than three minutes. La_0.6Ce_0.4Ni₅ is highly promising material for hydrogen storage due to its reversible hydrogen absorption and desorption capabilities, along with its high volumetric hydrogen density compared to many other options. These properties make it an ideal candidate for various applications such as fuel cell vehicles, portable power systems, thermal storage, and hydrogen compression.

This research explores the efficacy of dry pre-conditioning treatment coupled with accelerated CO₂ curing for mortar incorporating unreactive Calcium Lime Waste (CLW), with a specific focus on enhancing mechanical properties and CO₂ capture. The investigation was initiated by characterizing the CLW material through various microstructural examinations and toxicity tests using the Toxicity Characteristic Leaching Procedure (TCLP). Different proportions of CLW (0–40%) were blended into Ordinary Portland Cement (OPC) mortar, and their performance was systematically compared with that of control samples. The assessment parameters encompassed physical properties (workability and density), mechanical properties (compressive strength), and CO₂ capturing properties (carbonation depth) over the initial 24 h, scrutinized under both atmospheric air and accelerated CO₂ carbonation curing conditions. Thermogravimetric analysis (TGA), X-ray diffraction, and Mercury Intrusion Porosimetry (MIP) tests were conducted on the identified optimum CLW mortar, which was cured under accelerated CO2 carbonation conditions. The results exhibited that CLW is extremely rich in calcium and demonstrates the behavior of Ca(OH)₂, making it an excellent material for capturing CO₂. Despite exhibiting higher porosity than cement mortars, the optimum CLW mortar combination met the standard’s strength requirements for non-loadbearing structural applications. Additionally, the Advanced Neural Networks (ANN) model was designed to predict mortar properties—namely, compressive strength and carbonation depth—by learning from input features, including cement content, CLW content, and curing conditions. It was revealed that an increase of 1% in cement content enhanced the compressive strength by approximately 0.2406 MPa, while curing conditions such as CO2 exposure and dry pre-conditioning significantly impacted the carbonation depth, with adjustments up to 2.7692 mm under specific conditions. By absorbing CO₂ and incorporating it into mortars, CLW enhances durability and strength, making it a key step toward developing sustainable materials.

Energy emitted in the form of heat from various sources can be recovered and converted into usable electricity using thermoelectric generators (TEGs). In this study, the efficiency of a π-shaped thermoelectric module composed of p-type ZrMnZ (Z = In, Pb, Bi) legs and n-type Bi₂Te₃/SiGe alloys were investigated using MATLAB simulation software. The module efficiency was analyzed by varying the p-type legs (ZrMnIn, ZrMnPb, and ZrMnBi), n-type legs (Bi₂Te₃ and SiGe), and electrode materials (Al, Cu, and Ni), while keeping the ceramic plates (Al₂O₃) constant. The thermoelectric properties of the ZrMnZ alloys were evaluated using the WIEN2k code. Subsequently, the thermoelectric module was constructed, and its performance was simulated in MATLAB. The results reveal that the highest efficiency was achieved for the TEG comprising p-type ZrMnBi and n-type SiGe legs with Cu electrodes. Furthermore, it is observed that varying the leg height and incorporating suitable dopants can further enhance the device efficiency. Therefore, this study demonstrates that the half-Heusler alloys ZrMnIn, ZrMnPb, and ZrMnBi are promising candidates for efficient thermoelectric energy conversion applications.

Clay (c- Ti₃C₂), delaminated (d- Ti₃C₂), and silicon nanoparticle-incorporated (c- Ti₃C₂/Si and d- Ti₃C₂/Si) MXenes were synthesized, characterized, and electrochemically tested for potential energy storage uses. X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Raman spectroscopy were used to characterize the materials. The successful synthesis was confirmed by XRD analysis, which showed that delamination and silicon addition caused noticeable structural changes. The clay, delaminated, and silicon-incorporated MXenes were compared in terms of morphology and composition using SEM/EDX spectra, demonstrating increased surface area and altered elemental distribution due to delamination and Si doping. Raman spectroscopy provided additional insights into vibrational modes and structural changes resulting from these treatments. Electrical performance was evaluated using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanic charge-discharge (GCD). The d-Ti₃C₂/Si nanocomposite showed the highest specific capacitance of 374.5 F g⁻¹ at 1 A g⁻¹, outperforming pristine c-Ti₃C₂ thanks to improved ion diffusion and electrolyte access. Its larger surface area and better ion transport pathways made d-Ti₃C₂ superior in specific capacitance and rate capability compared to c-Ti₃C₂. Additionally, the d-Ti₃C₂/Si electrode reached an energy density of 18.03 Wh kg⁻¹ at a power density of 3.61 W kg⁻¹, confirming its enhanced energy storage performance compared to pristine c-Ti₃C₂. The silicon incorporation significantly affected the electrochemical behavior, as the c-Ti₃C₂/Si and d-Ti₃C₂/Si electrodes displayed distinct charge storage mechanisms.

Graphical abstract

Polyvinyl alcohol (PVA) is valued for its transparency and film-forming ability, but its limited chemical reactivity and weak nanofiller interactions restrict functional tunability. Partially oxidized PVA (OPVA), enriched with ketone and hydroxyl groups, provides a versatile scaffold for nanocomposite design. Transparent OPVA–graphene oxide (GO) films were fabricated via dopant-free aqueous casting with low GO loadings (0.5–1.5 wt%). FTIR and XRD analyses confirmed hydrogen bonding interactions and disruption of lamellar crystallinity, enabling nanoscale dispersion. UV–Vis–NIR spectroscopy revealed high transmittance (> 90%) and suppressed reflectance (~ 12%), while Tauc plots indicated a tunable bandgap (~ 2.0 eV) through GO-induced electronic coupling. Electrochemical impedance spectroscopy demonstrated humidity-responsive proton conductivity up to 6.0 × 10^− 3 S/cm at 90 °C under 100% relative humidity, achieved without sulfonation or external doping. Mechanical testing showed enhanced tensile strength and stiffness at 1.0 wt% GO, identified as the optimal loading, with incipient aggregation effects at higher concentrations. These synergistic trends establish a clear structure–property–performance relationship, positioning OPVA–GO nanocomposites as sustainable platforms for transparent photonic films, flexible optoelectronic devices, and renewable energy interfaces.

Polycrystalline silicon (poly-Si) solar cells remain the foundation of terrestrial photovoltaic energy production due to their cost effectiveness, mature manufacturing processes, and proven reliability. However, their outdoor power conversion efficiency is limited by significant optical reflection losses at the air–semiconductor interface, particularly under AM1.5 solar irradiance, which reduces light absorption and charge carrier generation. Antireflection coatings (ARCs) have emerged as an effective solution to mitigate these losses by enhancing light transmission into the active layer. This review evaluates a broad range of ARC materials including conventional options like SiNx, TiO₂, and MgF₂, as well as emerging zinc based, polymeric, and hybrid coatings and their impact on the optical and electrical performance of poly-Si solar cells. Emphasis is placed on optimizing refractive index, layer thickness, and spectral alignment with the AM1.5 spectrum to minimize reflectance. The influence of deposition techniques such as sputtering, physical vapor deposition (PVD), chemical vapor deposition (CVD), spin coating, dip coating, and sol–gel methods on coating quality, morphology, and interface passivation is also discussed. These factors directly affect key electrical parameters including short circuit current density (J_SC), open circuit voltage (V_OC), fill factor (FF), and overall efficiency (PCE). While theoretical studies on light interference and carrier dynamics were not covered, modelling efforts are included to analyze reflection, transmission, and resulting solar cell characteristics. Additionally, considerations such as long-term stability, thermal durability, environmental resistance, and material compatibility are highlighted as critical for practical deployment. Overall, this review offers a comprehensive perspective on the materials science, device engineering, and performance outcomes of ARCs for poly-Si solar cells, aiming to guide future research and industrial optimization toward high efficiency outdoor photovoltaics.