Friendly Energy Research Articles

Potential of Dry Leaf Waste as A Raw Material for Charcoal Briquettes Preparation as an Alternative Fuel

This research was motivated by the large potential of dry leaf waste in the campus environment of the University of North Sumatra and the awareness of the importance of appropriate innovation in the use of dry leaf waste as an environmentally friendly alternative fuel. The aim of this research was to determine the potential of leaf waste in the campus environment as a raw material for making environmentally friendly charcoal briquettes. The research method was observation, conducted in the campus environment of the University of North Sumatra, followed by calculating the amount of leaf waste produced per day, and testing continued with the production of dry leaf briquettes. The test results of the three combustions with different mixtures of raw materials in each combustion resulted in solid dry leaf briquettes that could ignite well. This study produced briquettes with proximate and ultimate tests that met SNI No.01-6235-2000 standards with a moisture content test of 4.35%, ash content test of 5.65%, carbon content test of 78.68%, calorific value of 6115 cal/g, and a burning rate of 1.5 grams/minute. Briquettes that meet SNI standards can become an environmentally friendly alternative energy source, a source of livelihood, and will certainly have a positive impact on waste management on the campus of the University of North Sumatra.

Constructing Dual Schottky Junctions for High‐Performance Zinc Anode

AbstractAqueous zinc ion batteries provide new solutions for achieving environmentally friendly and safe energy storage devices. Unfortunately, the further application is hampered by the growth of zinc dendrites caused by uneven zinc deposition, hydrogen evolution and other side interfacial reactions at the zinc anode. Herein, a multifunctional Bi‐Bi2O3 hybrid artificial interface layer is constructed on the surface of the zinc anode using an in situ conversion reaction. Among them, the Bi‐Bi2O3 Schottky structure not only significantly accelerates the migration of Zn2+ through its built‐in electric field, but also effectively improves the hydrogen evolution barrier (ΔGH*), thereby suppressing side reactions. Moreover, the Schottky contact formed between the interface layer and the metal zinc interface also regulates the electronic distribution state on the zinc surface and optimizes the deposition process of Zn2+, ensuring a more uniform and orderly zinc deposition process. Based on the synergistic effect of dual Schottky junctions, symmetric batteries achieve stable cycling for 2000 h under the conditions of 1.0 mA cm−2 and 1.0 mAh cm−2. The full cell assembled with α‐MnO2 as the cathode maintains capacity of 112.7 mAh g−1 after 1000 cycles at 1 A g−1 with a capacity retention rate of 84%.

Examining the Potential of Biogas: A Pathway from Post-Fermented Waste into Energy in a Wastewater Treatment Plant

Biogas has improved due to technological advancements, environmental awareness, policy support, and research innovation, making it a more cost-effective and environmentally friendly renewable energy source. The Generalized Linear Model (GLM) was employed to examine the relationship between purchased and generated energy from 2007 to 2023. Metrics such as deviance, log likelihood, and dispersion phi were examined to assess model fit. The Mann–Kendall test was utilized to detect trends in energy datasets. Biochemical Oxygen Demand (BOD5) and Chemical Oxygen Demand (COD) reduction was significant, exceeding 97% from 2014 to 2023. However, treated sewage displayed limited susceptibility to biological degradation, with COD to BOD5 ratios increasing from 2.28 to 6.59 for raw sewage and from 2.33 to 7.05 for treated sewage by 2023. Additionally, the efficiency of sewage purification processes was calculated, and multivariate regression analysis was conducted on gas composition data. Principal Coordinate Ordination (PCO) and k-means clustering were used for dimensionality reduction and biogas component clustering, respectively. This research showed that biogas from the waste water treatment process can be used, particularly in methane production. Technological advancements have made biogas production more efficient, enhancing energy generation within a circular economy framework.

Selective Self‐Assembly of Atomically Dispersed Iron and Cobalt Dual Atom Catalyst on Anisotropic Mesoporous Carbon Particles for High Performance Seawater Batteries

AbstractNa‐seawater batteries (SWBs) are environmentally friendly energy storage system that utilizes abundant seawater as an electrolyte alternative to conventional distilled water‐based and organic electrolytes. To achieve high energy efficiency in Na‐SWBs, it is necessary to enhance the activity of bifunctional oxygen electrocatalysts. In this study, an atomically dispersed iron and cobalt dual‐atom nitrogen‐doped lens‐shaped mesoporous carbon (FeCo‐LMC) particles is synthesized as a SWB cathode material using the spinodal decomposition of the polymer blend and selective precursor positioning. The well‐aligned mesoporous structure and synergetic effect of the dual‐atom site realize FeCo‐LMC as a comparable bifunctional oxygen catalyst with the lowest overpotential difference (EOER−EORR) among the other catalysts with natural seawater electrolyte. When applied to the SWB system, the FeCo‐LMC shows a highly improved charge/discharge performance compared to Pt/C and a stable cycling performance for 200 h. Density functional theory calculations reveal the enhanced oxygen catalytic activity of FeCo‐LMC owing to electron delocalization and d‐band center adjustment of FeN4–CoN4 structure.

High-entropy perovskite (Pr1/6Nd1/6Sm1/6Ba1/6Sr1/6)6/7(Mn1/6Co)6/7O3-δ as a highly active and CO2 durable cathode for solid oxide fuel cells

Solid oxide fuel cells (SOFCs) are environmentally friendly energy conversion devices that convert the chemical energy in fuels directly into electrical power. The development of high-catalytic activity and durability cathode materials is crucial for the commercialization of SOFCs. Herein, a novel A-site deficient high-entropy perovskite oxide (Pr1/6Nd1/6Sm1/6Ba1/6Sr1/6)6/7(Mn1/6Co)6/7O3-δ (PNSBSMC) was designed. The strong disorder effect associated with entropy increase in high-entropy perovskite oxide is anticipated to accelerate oxygen reduction reaction (ORR) kinetics. PNSBSMC demonstrates excellent catalytic activity for oxygen reduction, primarily due to the entropy-driven enhancement that promotes oxygen adsorption, dissociation, and charge transfer dynamics. The increase in entropy not only significantly mitigates the thermal expansion of PNSBSMC but also provides additional pathways for ionic/electronic transport. At 800 °C, the PNSBSMC-based single cell achieved a remarkable peak power density of 1.41 W cm−2, representing an 88.0 % improvement over the single-phase PBC. Additionally, PNSBSMC demonstrates superior performance stability and CO2 tolerance. These findings suggest that high-entropy PNSBSMC perovskite holds significant potential as an effective cathode for SOFCs. This study offers new insights for the future development of high-stability, high-activity SOFC cathode materials.

Multi‐aspect assessment and multi‐objective optimization of preheated tallow biodiesel‐diesel blend as alternate fuel in CI engine

AbstractThis study meticulously examined the impact of preheated tallow biodiesel on the performance and emission characteristics of a diesel engine. Employing a single‐cylinder, water‐cooled diesel engine configured with exhaust gas recirculation in this investigation, exhaust gas temperature (EGT) could be used to preheat the biodiesel, reducing its viscosity and density. This improvement in viscosity and density could enhance the injection process, which is often hindered by the higher density and viscosity of biodiesel compared with diesel fuel. The investigation achieved a peak preheat temperature of 70°C for the biodiesel, leading to notable improvements in brake thermal efficiency and brake power, particularly under high‐load conditions. A significant reduction in emissions was observed, with hydrocarbon and carbon monoxide levels decreasing by 46.87% and 50%, respectively, when using preheated biodiesel. To refine the engine's performance further, this study utilized response surface methodology (RSM) for the optimization of operational parameters, including injection timing, engine load, and biodiesel preheat temperatures. Optimal conditions were identified at an injection timing of 21° before top dead centre, a preheat temperature of 64°C, and an engine load of 45.45% for which output response was 18.68% brake thermal efficiency, 307°C EGT, 0.0247% vol. CO, 15.32 ppm hydrocarbons, and 131.37 ppm nitrogen oxides (NOx). The successful implementation of preheated tallow biodiesel signifies a crucial step forward in the pursuit of a more sustainable and efficient transportation industry. This advancement holds the promise of reducing reliance on traditional fossil fuels, thereby contributing to the global efforts towards achieving a more environmentally friendly energy landscape.

Efficient Water Reforming of Biomass to H2 via Well‐Organized Redox‐Neutral Cleavage of C−C, O−H and C−H Bonds

AbstractHydrogen (H2) is a clean and environmentally friendly energy carrier. The depletion of fossil fuels makes renewable H2 production highly desirable. Water reforming of renewable biomass to hydrogen, with a relay of natural photosynthesis to biomass, would be an indirect pathway to realize the ideal but extremely challenging photocatalytic overall water splitting to hydrogen, with favorable thermodynamics. Since the seminal work of water reforming of biomass in 1980, great endeavors have been made. Nevertheless, hitherto, the entire kinetic pathway has been elusive, which seriously limits the reforming processes. Using a designed well‐organized redox‐neutral cleavage of C−C, O−H and C−H bonds enabled by photoelectrocatalysis, here, we show the efficient water reforming of biomass to hydrogen at room temperature, with a yield up to 93 %. The clear insights into the kinetic pathway with oxidation of carbon radicals to carbon cations as the indicated rate‐determining step, would cast brightness for efficient and sustainable hydrogen production to accelerate the hydrogen economy.

A Double‐Arch‐Structured Hybrid Triboelectric and Piezoelectric Nanogenerator Based on Polyvinylidene Fluoride/Graphene Oxide Composite Films

In this study, a methodology for fabricating double‐arch triboelectric and piezoelectric composite nanogenerators using polyvinylidene fluoride (PVDF) and graphene oxide (GO) is presented. Initially, nanofiber films comprising PVDF/GO are synthesized through electrostatic spinning. Subsequently, the PVDF/GO film is integrated with cotton fibers and a copper electrode to construct the triboelectric layer. In contrast, another portion of the PVDF/GO film, alongside a copper electrode, comprises the piezoelectric layer, with the central copper electrode acting as a common electrode. Finally, a double‐arch structure is established by employing polyethylene terephthalate film to facilitate synergistic operation between the triboelectric and piezoelectric layers. In the experimental results, it is indicated that the maximum open‐circuit voltage and short‐circuit current of the triboelectric layer of the double‐arch structure are 330 V and 36 μA, respectively, representing increases of 44% and 50% compared to those of the sandwich triboelectric structure. Additionally, the maximum open‐circuit voltage and short‐circuit current of the piezoelectric layer are 22 V and 4 μA, respectively, reflecting enhancements of 57% and 100% over those of conventional sandwich piezoelectric structures. The output power of the double‐arch composite nanogenerator is capable of lighting up 120 light‐emitting diodes. Thus, this composite nanogenerator shows great potential as an environmentally friendly energy source.

Green energy using oscillatory baffled reactors: advances in biodiesel production from high free fatty acid karanja oil

Abstract The global demand for sustainable and ecologically friendly energy sources has spurred biodiesel research. Civilization, urbanization, and population growth have drastically boosted transportation energy consumption. Energy demand is causing fossil fuel crises. Replace petroleum diesel to solve energy and environmental problems. Biofuels have very vast scope in the area of energy sector. Karanja oil, derived from the seeds of the Karanja tree (Pongamia pinnata), is a promising biodiesel feedstock due to its high Free Fatty Acid content. This study uses Oscillatory Baffled Reactor (OBR) to produce biodiesel from Karanja oil. The feedstock is high-FFA Karanja oil trans-esterified in two steps. In OBR, reaction time is only 15 min, whereas in conventional reactor it takes 1–2 h to produce biodiesel. Optimizing biodiesel synthesis involved varying H2SO4 concentrations from 1 vol% to 5 vol% and 0.3 to1.0 wt% of NaOH concentration for first and second step respectively. Oil-to-alcohol molar ratios 1:6, 1:9 and 1:12. Optimization occurs at 1:12 oil-to-alcohol ratio, 1 vol% H2SO4 catalyst, and 0.6 wt% NaOH catalyst. Studies have also examined how catalyst concentration and oil: alcohol molar ratio affect biodiesel conversion and physical qualities such kinetic viscosity, specific gravity, and acid value. This study shows that OBR can increase biodiesel production from high-FFA Karanja oil, which further opens up opportunities for additional study and improvement.

Solid-state anaerobic digestion of sweet corn waste: The effect of mixing and recirculation interval

The mixing and sludge recirculation interval is one of the key successes of the solid-state anaerobic digestion process, a promising technology for converting high-solid agro-industrial wastes to renewable energy. This study employed a pilot-scale completely stirred tank reactor to examine biogas production from sweet corn waste, including corn cobs, husks, and seeds. The reactor was operated as solid-state anaerobic digestion at an ambient temperature. The mixing and recirculating intervals were set to non-mixing and mixing for 10 minutes every 3, 6, and 12 hours. The initial total solid of the feedstock was 25%, while the hydraulic retention time was 30 days. The results showed that during the mixing and recirculation every three hours, the highest chemical oxygen demand, total solid, and volatile solid (VS) removal efficiencies were 85.42%, 62.92%, and 64.59%, respectively. The ratio between volatile fatty acid and alkalinity ranged between 0.20 and 0.30 without any sign of system failure. The highest specific methane yield of 766 L/kg VSadded was obtained in the experiment with mixing and recirculating intervals every 3 hours. It was found that the modified Gompertz model could effectively fit the methane yields with an R2 of 0.9667. The modeled methane production potential and the maximum methane production rate were 867.40 NL/kg VSadded and 132.01 NL/kg VSadded-d, respectively. Additionally, the levelized cost of the biogas produced from the solid-state anaerobic digestion of the sweet corn waste was calculated to be 0.61 USD/kg. The findings of this study can serve as a guide for the design and operation of the SS-AD system, which aims to transform various types of lignocellulosic waste into environmentally friendly energy.

Enhanced low-field energy storage performance and dielectric stability in (Bi0.4Sr0.2K0.2Na0.2)(Ti1-xZrx)O3 high-entropy ceramics via B-site modification

The current global energy situation is tense, necessitating the development of high-efficiency, low-cost, and eco-friendly energy materials. In this study, a series of perovskite lead-free relaxor ferroelectric ceramics, denoted as (Bi0.4Sr0.2K0.2Na0.2)(Ti1-xZrx)O3 (BSKNT-xZr) were designed to enhance the storage performance. The findings indicate that all samples exhibit a single perovskite structure. As the Zr4+ content increases, the configurational entropy of the samples increases, the cell volume expands, and the hysteresis loops become finer, while maintaining a high maximum polarization (Pm) and effectively enhancing the energy storage performance. For the ceramic with x = 0.10, the energy density (Wtot), recoverable energy density (Wrec), and energy storage efficiency (η) values were determined to be 3.16 J/cm3, 2.67 J/cm3, and 84.3%, respectively, under an electric field of 230 kV/cm. Moreover, the introduction of Zr4+ reduces the relative permittivity and broadens the temperature range (ΔT) that simultaneously satisfies Δε/ε150°C ≤ ±15% and 0 ≤ tanδ ≤ 0.02. This investigation underscores the potential of BSKNT-xZr ceramics as high-performance, cost-effective, and environmentally friendly energy materials for addressing global energy requirements.

Bacterial film-based degradable triboelectric nanogenerator for both contact and non-contact sensing

As an emerging environmentally friendly energy conversion device, degradable triboelectric nanogenerators (TENGs) play an important role in self-powered sensing, health care and human–machine interaction. However, traditional degradable materials used in TENGs often suffer from limited material sources and complex preparation processes, restricting large-scale production for widespread applications. Here, we propose a simple and efficient way to prepare degradable TENGs with inactivated bacterial film, taking advantage of wide source, self-proliferation and easy culture properties of bacteria. The prepared bacterial film-based TENG (BF-TENG) has stable electrical output, good durability and fatigue resistance, along with superior capabilities in both contact and non-contact sensing. In contact mode, the BF-TENG can generate a peak voltage of up to 83.3 V, which is employed for accurate Morse code transmission. In non-contact mode, the BF-TENG is capable of effectively perceiving the target polymer at a distance of 150 cm. The non-contact LED control circuit and a sensing array based on BF-TENG further demonstrate its practical potential for gesture recognition and spatial position perception. Furthermore, the fully degradable nature of BF-TENG ensures effortless disposal after use without environmental impact, serving as a promising solution for the new generation of eco-friendly and sustainable sensing devices.

Synthesis of nanochitosan from oyster pearl shell (Pinctada maxima) as renewable energy candidate

The increase in energy needs must be balanced by environmentally friendly technological innovations. Chitosan polymer is one of the technological innovations of energy materials that are being developed by many developed countries. This research aimed to identify the potential of oyster pearl shell waste as a source of electrolyte polymers. The study was conducted experimentally by synthesizing chitosan nanoparticles from chitosan using the ionic gelation method. Chitosan is obtained through the isolation method from Pinctada maxima oyster pearl shell waste. The isolation method is carried out by three processes: deproteination, demineralization, and deacetylation. Several characterizations were carried out to analyze the material from the synthesis, including a proximate test, FTIR analysis, and PSA analysis. Isolated chitosan was identified to have a deacetylation degree that reached 88.63% with the formation of OH and NH2 functional groups. In general, the proximate tets data has shown that the obtained chitosan already meets the Indonesian standard SNI 7949:2013. PSA analysis resulted in differences in size distribution, PDI, and zeta potential between chitosan and chitosan nanoparticles. The results were obtained by the average distribution of chitosan particle size of 52.043 μm and chitosan nanoparticle size of 2.3365 μm—the analysis of the potential zeta of chitosan -3.9 mV and chitosan nanoparticle -21,6 mV. Thus, changes in the size of the chitosan material affect its potential PDI and zeta values. The change of these two values is a good indicator of the initial data and the potential of the material as an energy material. Therefore, chitosan polymer is an electrolyte material that can be used as a candidate for environmentally friendly renewable energy materials

THE EFFECT OF SPUTTERING TEMPERATURE OF TiO2/ITO-PEN PHOTOANODES IN DYE SENSITIZED SOLAR CELL

Currently, the world is facing a major crisis related to the lack of sustainable, safe, and environmentally friendly energy resources. Dye sensitized solar cells (DSSC), another name for third-generation solar cells, have gained a lot of interest due to ease of production, cheapness, and environmental friendliness. The photoanode is among DSSC's most crucial components. In this research, the active layer on the TiO2 photoanode was optimized to improve the efficiency of the DSSC. The active layer was deposited using Radio Frequency (RF) magnetron sputtering on an Indium tin oxide-polyethylene naphthalate (ITO-PEN) substrate. The sputtering temperature was varied to 25, 80, 120, and 160℃ for one hour. The thin film TiO2/ITO-PEN photoanode will be characterized by means of X-ray Diffraction (XRD), Ultraviolet-Visible (UV-Vis) spectroscopy, and solar simulator. The XRD analysis shows that the best crystal size is 14.55 nm for a sputtering temperature of 80℃. According to the UV-Vis data, optical absorption increases with increasing sputtering temperature. The wavelength range where the absorption peak occurs is 252–465 nm, and the smallest value of the energy gap is found at a sputtering temperature of 25℃ with a value of 3.02 eV. For the TiO2/ITO-PEN thin layer, the maximum efficiency was achieved at 0.12% at a sputtering temperature of 25°C.

GAPS OF INDIAN ELECTRICAL ENERGY SECTOR AND ITS OPTIMAL MITIGATION BY USING OPTIMAL UTILIZATION OF INDIAN RENEWABLE ENERGY POLICY WITH THE HELP OF THE P&O MPPT TECHNIQUE

Developing countries, especially, India, depend importantly on energy sources to perform their country’s industrial and economic activities. Mainly the two factors continuous population growth of the country and the rapid growth rate of industrialization of the country, the gap between electrical energy supply and demand for electrical energy is slowly and consistently increasing. To resolve this unevenness, there is a jointly planned attempt is required to enhance the contribution of renewable energy in the all over mix of energy. Despite these attempts, unexpected surges caused by the sector of domestic energy consumption could lead to important shortfalls between energy requirements at peak demand and available supply in India. As a solution to this challenge, the Union government of India has launched a new policy, named PM SURYA GHAR: MUFT BIJLI YOJANA, targeted to handle this crucial problem head-on. This initiative requires addressing the increasing energy demand by promoting the utilization of solar power in households throughout the length and breadth of the country. With the implementation techniques of Photo voltaic optimization, this analysis explores how such types of strategies can play a significant role in filling the gap between the energy supply-demand in the Indian context. Employing the solar energy potential and optimizing and utilization of solar energy, creates a path to not only meet the enhancing energy requirements but also creates the path for a more environmentally friendly and sustainable energy in India. By integration of innovative technologies and solutions of renewable energy holds the key to ensuring a balanced, sustainable, stable energy supply for the future of India and country’s growth and development.

Perancangan dan Analisis Tekno Ekonomi PLTS On-Grid System sebagai Supply Energi Listrik Masjid Al-Istiqamah Politeknik Negeri Jember

The increasing energy demand is directly proportional to the growing population and technological advancements. The energy needs in Indonesia largely rely on fossil fuels, which are limited and environmentally unfriendly due to their emission characteristics. The potential of solar energy in Indonesia is around 4.8 kWh/m2, making it a renewable and environmentally friendly energy source that can be utilized for Solar Power Plants (PLTS). The aim of this research is to design an on-grid PLTS system and conduct techno-economic analysis using PVSyst software. This design requires 14 Longi Solar/LR5-72HPH-550M solar panels and 1 Huawei SUN2000-6KTL-M1 inverter. The estimated electricity production is 10,852 kWh/year in the first year. The initial investment cost for this PLTS system is Rp. 120,343,517.00, with estimated savings over 25 years amounting to Rp. 270,115,412.00. Economically, based on the feasibility analysis using the LWBP tariff calculation method, the NPV is Rp. 2,174,707.00, BCR is 1.68, and PBP is 11.8 years. Meanwhile, based on the feasibility analysis using the LCoE calculation method, the NPV is Rp. 74,877,690.00, BCR is 2.61, and PBP is 7.5 years. Based on the conducted research, the construction of this PLTS is deemed feasible to be implemented.

Discovery and Analysis of Key Core Technology Topics in Proton Exchange Membrane Fuel Cells Through the BERTopic Model

As a core component of clean energy technology, proton exchange membrane fuel cells (PEMFC) play a crucial role in promoting the evolution of energy structures and realizing sustainable development, representing an environmentally friendly energy conversion strategy. This paper identifies the key core technology themes in the field of the proton exchange membrane fuel cells by constructing patent and paper datasets in the field, applying the BERTopic model for theme identification, and calculating the key core technology scores of each theme using the importance, innovativeness, and high competitiveness barriers to identify the key core technology themes in the field, so as to provide guidance and references for the relevant research and practice. The results of the study show that patent documents and academic papers show obvious differentiation in technical themes: the key core technologies identified in patent texts include ‘battery separator materials’, ‘rubber sealing materials’, and ‘porous carbon fibre materials’. The key core technologies identified in the academic paper of the thesis include ‘palladium-based electrocatalys’, ‘graphene oxide composite film’, and ‘platinum-graphene oxide catalyst’.

Polyoxometalate‐Derived Photocatalysts Enabling Progress in Hydrogen Evolution Reactions

AbstractPhotocatalytic water splitting is capable of converting abundant solar energy into environmentally friendly and renewable chemical energy, presenting a promising solution to alleviate the energy crisis and combat environmental pollution. The development of high‐performance photocatalysts is crucial for significantly improving the efficiency of the hydrogen evolution reaction (HER) involved. Polyoxometalate (POM)‐derived materials, known for their tunable compositions, diverse structures, electron storage/release capabilities, as well as quasi‐semiconductor photochemical properties, serve as highly efficient catalysts in sustainable photosynthesis. This comprehensive review navigates the latest advancements in the assembly strategies and HER performance of POM‐based crystalline materials. It also discusses the composite materials formed by infiltrating POM into metal‐organic frameworks (MOF) and examines the roles of transition metal compounds derived from polyoxometalates, such as sulfides and carbides, in photocatalytic HER. Emphasis is placed on the prospects for the future development of POM‐based compounds as photocatalysts, along with several strategies and outlooks that could facilitate their progress. POM‐derived materials are believed to have significant potential to enhance hydrogen production efficiency while maintaining thermal stability in HER processes.

Разложение аммиака на Co-Al2O3 /SiO2 катализаторах: влияние способов восстановления кобальта

The focus on "green" energy requires the search for environmentally friendly energy storage systems. The reason for choosing ammonia as a potential storage for hydrogen is its high energy capacity and the absence of carbon and nitrogen oxide emissions during decomposition. Herein, we tested Co-Al2O3/SiO2 ammonia decomposition catalysts that had been pre-activated via cyclic hydrogenation-carburization-hydrogenation (RCR) and reduction-oxidation-reduction (ROR) procedures versus the conventional cobalt oxides reduction with hydrogen (R). The samples were characterized by H2-TPR, TEM and synchrotron X-ray diffraction techniques, which revealed that the structural properties of the catalysts were not modified by the reaction. Since the activities of the tested catalysts and the effective reaction barriers appeared to be close, the easiest-to-prepare catalyst R was chosen for the long-term catalytic trial (500 h), and it showed excellent performance stability.

Design and simulation of highly efficient CZTS/CZTSSe based thin-film solar cell

Thin-film solar cells are a substitute for more common crystalline silicon solar cells, which consist of thin semiconductor layers. Thin-film materials comprise direct bandgap and can absorb sunlight more efficiently than silicon. In this article, a double-absorber-based thin-film solar cell comprising CZTS/CZTSSe is designed and optimized through numerical simulation. The proposed solar cell structure consists of a transparent window layer made of aluminum-doped zinc oxide, followed by an intrinsic zinc oxide layer, an n-type cadmium sulfide layer, and a p-type combined absorber layer of copper zinc tin sulfide (Cu2ZnSnS4) (CZTS) and copper zinc tin sulfur-selenium alloy (Cu2ZnSn(S,Se4)) (CZTSSe). The structure is further optimized by introducing two interfacial layers between CZTSSe/CZTS and CZTS/CdS. The highest conversion efficiency is achieved by adjusting the thicknesses of the layers, the doping densities in different layers, and the defect densities in the two absorber layers. The optimized model, with a total thickness of 2.01 μm, demonstrates an open-circuit voltage (Voc) of 0.7669 V, a short-circuit current (Jsc) of 48.57740 mA/cm2, a fill factor (FF) of 70.61%, and efficiency (η) of 26.31%. These results suggest that CZTS is a promising candidate for replacing other thin-film photovoltaic materials, such as CdTe. The proposed double-absorber thin-film solar cell optimizes doping concentration, thickness, and defect density to enhance performance metrics and efficiency while utilizing non-toxic materials to promote cost-effective, environmentally friendly energy solutions.