Materials for Renewable and Sustainable Energy最新文献

Research into perovskite solar cells (PSC) is making significant progress toward contributing to renewable energy generation. With perovskite solar cells, power conversion efficiency above 25% has been reported, making it a promising technology. The existing module perovskite-based type cells indeed display the best performance of all the types available in the markets, even with the excess temperature conditions as concerns. However, the chances of perovskite-based types providing sustainable energy are low, and more work is still required. This article discusses predictions about workability issues and the existence of a high forbidden zone that came with PSCs. It then reviews the degradation mechanisms and solutions to overcome these stability problems. PSCs have a big commercialization issue, which may concern their stability because their productivity is unstable in real-time operation, especially under long run-time conditions. In addition, the review expands on how PSC materials effectively transport charges and how the various barriers present in PSCs are affected. The article goes into more detail on how perovskite crystal orientation has lately been significant, which modern design is suitable for perovskite solar cells, how different layers in perovskite cells are made, and what kind of materials are laid between electron transport layers (ETLs) and buffer layers. The final part of the article provides insight into the methods for overcoming degradation and enhancing the stability PSCs, which is crucial for commercialization.

The transition to sustainable energy has driven extensive research into perovskite solar cells (PSCs) as promising candidates for next-generation photovoltaics. Despite their remarkable efficiencies, the commercialization of PSCs remains hindered by lead toxicity and material instability. In this study, we investigate a lead-free samarium-based double perovskite oxide, Sm₂NiMnO₆ (SNMO), as the active absorber layer in an innovative inverted, hole transport layer (HTL)-free PSC architecture. Using SCAPS-1D simulations, we optimized the device configuration and achieved a power conversion efficiency (PCE) of 10.93%, with an open-circuit voltage (V_OC) of 0.8 V, a short-circuit current density (J_SC) of 16.46 mA cm⁻², and a fill factor (FF) of 82.14%. Notably, increasing the SNMO absorber thickness enhanced light absorption in the red spectral region, shifting the external quantum efficiency (EQE) peak from 380 nm wavelength at a thickness of 50 nm to approximately  620 nm at 1 µm. Furthermore, we investigated various electron transport layers (ETLs) and found that the indium tin oxide (ITO) exhibited superior PV performances, boosting the PCE to ~ 12.6% due to its excellent conductivity and optimal energy band alignment with SNMO. These findings establish SNMO as a promising absorber material for environmentally friendly PSCs, paving the way for cheaper, simpler, scalable, and sustainable photovoltaic solutions. This work highlights the potential of HTL-free architectures to reduce costs and complexities while maintaining competitive efficiencies, marking a significant step forward in the development of lead-free solar technologies.

Fossil fuels dominate the world's energy consumption, including transportation, chemicals, and materials generation. Conversely, using conventional energies has resulted in massive environmental damage and climate change. This study looks into developing briquettes from sorghum stalks and groundnut husks utilizing cow dung as a binder for fuel production using the low-pressure compaction method, an important renewable energy source. The briquettes were labeled with cow dung binder compositions (5–25%), ratios (75–95%), and particle sizes ranging from 1 to 3 mm. The raw materials were collected and cleaned, then sun-dried, followed by carbonized and ground using a mortar grinder. Design of Expert (DOE) software, Excel, and analysis of variance (ANOVA) were used to perform numerical and graphical data analyses. After briquetting, the proximate properties of the moisture content were 3.16%, fixed carbon 13.04%, volatile matter 80.20%, and ash 3.6%. The briquette had 51.56% carbon, 6.302% hydrogen, 0.0042% nitrogen, 42.134% oxygen, and 0.00093% sulfur. The calorific value of mixed briquettes varies from 20.08 to 24.36 MJ/kg. The maximum calorific value was achieved with a particle size of 1 mm and a 25% cow dung binder content, as a minimal particle size was preferred. According to the analysis, the created briquettes were smokeless, low in Ash content, and had a high Calorific value for burning above 17 MJ/kg for industrial driving and above 13 MJ/kg for household usage. The result of standardization on the diet of cow dung revealed that grain-fed dung offered a higher calorific value of 20 MJ/kg, while a higher shatter resistance of 90% was recorded using grass straw fed, which outlines the importance of diet on the efficiency of the binder. Developing briquettes from these biomasses can increase job prospects, decrease greenhouse gas emissions, and improve waste management.

Graphical Abstract

The cathode in a molten carbonate fuel cell (MCFC) was made using the tape casting method from a slurry with a suitable chemical composition consisting of porogen, allowing it to achieve a porous structure. Currently used porogens in creating cathode structures are synthetic polymers, which release hazardous substances into the environment during thermal removal. Therefore, it is very important to find a safer alternative before industrial production of fuel cells begins and reduce its impact on the environment. The research aimed to analyze the possibility of using various porogens to obtain a fuel cell's cathode microstructure and compare them to a reference cathode. The electrodes were produced using cheap, accessible, and natural porogens. Chosen porogens were post-production waste materials such as wheat straw, hemp, and beet pulp. They were used solo or coupled to create the cathode of MCFC, thoroughly characterized in the context of morphology, structure, and chemical composition. After optimization, final MCFC cathodes were characterized by SEM, Archimedes porosimetry, gas porosimetry, and gas permeability. The highest power density (100 mW/cm²) was obtained for the cathode, which was made with starch and straw, while starch and PVB enabled the achievement of 90 mW/cm² of the MCFC cathode.

Alternative proton exchange membranes (PEMs) with high proton conductivity must be fabricated at reasonable costs to qualify as commercially used proton-exchange membrane fuel cells (PEMFCs). As a result, composite membranes containing sulfonated poly(ether ether ketone) (SPEEK) blended with various quantities of partially oxidized polyvinyl alcohol (OPVA) at 5 wt%, 10 wt%, and 20 wt% were developed for PEMs. At room temperature, the water uptake capacities of the SPEEK membranes containing 5, 10, and 20 wt% OPVA were 45%, 75%, and 109%, respectively. Correspondingly, the proton conductivities of SPEEK containing 5, 10, and 20 wt% OPVA were 22, 48, and 80 mS cm⁻¹ at 110 °C, respectively. Compared with prestine SPEEK, OPVA/SPEEK have greater strength, stiffness, and thermal stability. The characterization results indicated that the strong hydrogen bond network that evolved between OPVA and SPEEK provided more jump sites for proton transfer. This study confirmed that OPVA/SPEEK membranes are effective as proton exchange membranes.

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A two-step electrodeposition approach was applied to deposit Sn/C layers on a Ni foam substrate. The first step was the deposition of the Sn layer using two electrodeposition modes (direct and pulsed electrodeposition) with different parameters (duty cycle, time on/off, and effective time). The second step was to deposit carbon on the Sn layer by direct electrodeposition. The surface morphology, chemical composition, and phases of deposited layers were investigated and the electrochemical behavior of Sn/Ni and C/Sn/Ni anodes was characterized. The pulsed electrodeposition technique with a lower duty cycle (15% duty cycle with time ratio t_on/_off = 3/17 for 2 min) produced more uniform and compacted deposits, compared to the non-uniform and dendritic morphology obtained after high duty cycles (50%) as well as direct electrodeposition. After the direct electrodeposition of carbon on the pulsed electrodeposited Sn, a uniform layer containing ~ 10% C, 38% Sn, 45% Ni, and 7% O, was detected. Analysis of this layer confirmed the presence of Ni, Sn, and amorphous C. Electrochemical characterization showed that the C/Sn/Ni anodes with a 94 Ω polarization resistance, a 0.105 V/decade anodic Tafel slope and 0.202 V/decade cathodic Tafel slope manifested the highest apparent and intrinsic catalytic activities. The peak current for the C/Sn/Ni samples was higher than the peak current for the Sn/Ni samples at all scan rates, indicating higher electrochemical reactivity. The linear relationship between the peak current and the scan rate's square root suggests that diffusion controls the charge transfer process.

Solar energy harvesting and conversion has attracted a lot of scientific interest because solar energy is believed to be clean and sustainable. In this study, we report the synthesis of porous TiO₂ by sol-gel method and later doped with Thulium rare earth ions (Tm³⁺) for potential application in organic solar cells as electron transport layers (ETL). Additionally, density functional theory (DFT) calculation was performed with CASTEP computational suite to explore further the optoelectronic and charge transfer mechanisms in the Tm(III)-doped TiO₂ nanomaterials. Thereafter, the experimental material’s band gap values were extracted and used in the numerical simulation of the designed organic solar cell with a general configuration of FTO/TiO₂/PBDB-T/ITIC/Cu₂O/Ag, via SCAPS-1D numerical simulator. The experimental results showed a steady reduction in the band gap of TiO₂ with increased Tm³⁺ doping. The electrical conductivity properties showed an enhanced feature when TiO₂ was doped with Tm³⁺ nanoparticles. The calculated band gap from the density functional theory study shows a similar decreasing band gap trend with that of the experimental data, suggesting the transport properties from DFT are sufficient to describe the experimental data. The electronic transfer behaviour is analogous to metal-metal and metal-oxides transport features, which can be attributed to Ti – Tm and Tm – O – Ti hybridizations, as indicated in the orbital state alignment. The best performing modelled device with Tm(III)-doped TiO₂ (1.0 mol%) as ETL attained a PCE of 21.83%, V_oc of 1.54 V, J_sc of 31.87 mA cm^− 2 and FF of 44.44% which was attributed to better charge transfer characteristics and effective band alignment between the ETL and absorber, thus, better efficiency. The study proposes that Tm(III)-doped TiO₂ can act as a suitable n-type material that can propel the realisation of high-performance OSCs for commercialization in the future.

This work improved energy efficiency, stability and energy stability in organic and organic perovskite solar cells, by using titanium dioxide as anti-reflective coating on silver. The use of graphene oxide-nickel oxide layer as a hole-transporting layer enhanced carrier mobility in addition to incrementing stability. The outcomes that have been meticulously extracted and analyzed from the finite-difference time-domain (FDTD) simulations provide compelling evidence that this particular methodology can be adeptly utilized to significantly enhance the capability to attain a remarkably broad absorption spectrum across a wide range of wavelengths, specifically those identified frorm 200 nm to 900 nm, which are of critical importance in solar cell applications. Optical analysis was conducted by Maxwell method. Dielectric plasmonic wire grating was proposed to increase optical absorbance and achieve maximum current. The electrical analysis of the structure was based on Poisson’s equations. Optical analysis of the inorganic halide perovskite revealed current density, open circuit voltage, fill factor, and power of 34.294 mA/cm², 1.04 V, 0.83369817, and 1.64 mA/cm². The energy conversion efficiency was also 29.3%.

Non-fullerene acceptors are promising materials for organic solar cells because of their flexibility and low cost; however, their long-term stability remains a critical challenge. In this study, we investigate the degradation mechanisms of conventionally structured solar cells (ITO/PEDOT: PSS/PM6/Y7/PDINO/Ag) under different environmental conditions: nitrogen preservation, encapsulation, and air exposure. Using the metal-insulator-metal (MIM) model, we simulate the current-voltage characteristics and extract key parameters to understand the physical mechanisms governing device degradation. The results show that air exposure primarily affects the anode interface, reducing the interfacial dipole energy and shifting the Fermi-level alignment of PEDOT: PSS, which is crucial for efficient hole extraction. This process leads to a deterioration in the hole transport properties over time, significantly affecting device performance. In contrast, the cathodic interface remains stable, suggesting that degradation is largely driven by changes in the hole transport layer. These findings provide critical insights into the interfacial degradation mechanisms of the NFA-based solar cells. Understanding these effects will aid in the development of strategies to enhance the stability and efficiency of organic photovoltaic devices for long-term operation.