Ultimate Conversion Research Articles

Enhancing Efficiency and Stability in Carbon-Based Perovskite Solar Cells by Double Passivation with Ultralow-Cost Coal-Derived Graphene and Its Derivatives.

Coal-derived carbon nanomaterials possess numerous superior features compared to other classic carbon, such as readily accessible surfaces, tunable pore structure, and facile and precise surface functionalization. Therefore, the controllable preparation of coal-derived carbon nanomaterials is anticipated to be of great significance for the performance improvement and commercialization process of carbon-based perovskite solar cells (C-PSCs). In this study, we successfully synthesized highly stable and commercially valuable graphene oxide (GO) and reduced graphene oxide (rGO) utilizing coal. Compared to traditional methods and commercial graphene, the chemical oxidation and pyrolysis process used in this study is mild and simple, offering the advantages of controlled composition and the absence of other impurities. GO or rGO was incorporated into the top of the SnO2 electron transport layer (ETL) of C-PSCs. Under optimized conditions and ultraviolet-ozone (UVO) irradiation, the ultimate power conversion efficiency (PCE) increased from the unmodified 12.4 to 14.04% (based on rGO) and 15.18% (based on GO), representing improvements of 22 and 31%, respectively. The improved photovoltaic performance is mainly owing to enhanced charge transport capabilities, denser interfacial contacts, improved carrier separation properties, increased conductivity, and abundance of hydrophilic functional groups in GO, which can form more stable hydrogen bonds with SnO2. After being stored at room temperature and ambient humidity for 30 days, the modified, unpacked devices retained 87% of the highest power conversion efficiency (PCE). This study introduces a practical and manageable method to enhance the performance of C-PSCs by using functional carbon nanomaterials derived from coal.

Development of cyanate ester-oligosiloxane copolymers for deployable satellite applications

Binary blends of an α,ω-hydroxyoligosiloxane (with degree of polymerization, n = 39) with an oligomeric cyanate ester (Primaset™ PT-30, 1) are prepared as microphase-separated, monolithic samples. The uncured blends display complex viscosities of 21–97 Pa s at 30 °C depending on composition, rendering them suitable for infusion processes at 70 °C. This α,ω-hydroxyoligosiloxane undergoes co-reaction with (1) to yield network structures. Initiation using copper(II) acetylacetonate/nonylphenol reduces the onset of polymerization of the 190210 binary blend by some 99 °C and a value of 61–62 kJ/mol cyanate groups is obtained for the ucatalyzed polymerization of the homopolymer (1) and the binary blend 19525, while there was little difference in the enthalpy when catalyzed with copper (64 kJ/mol. OCN), cobalt (66 kJ/mol. OCN), and iron (60 kJ/mol. OCN), although the shape of the exotherm and thus the mechanism were changed significantly. A short initial cure cycle (170 °C, 1 h) effects a high initial conversion of >80 %, while a second post cure step (200 °C 1 h) yields an ultimate conversion of at least 93 %. The cured binary 190210 binary blend displays good thermal stability (Tdec5% = 429 °C and char yield = 62.4 % at 800 °C, compared with (Tdec5% = 433 °C and char yield = 68.0 % at 800 °C).

Electron spin resonance spectroscopy using a Nb superconducting resonator

Recently, micro-resonator structures have demonstrated considerable enhancement of ESR spectroscopy. The high-quality factor and confined mode of these resonators (cavities) lead to an enhanced spin-cavity interaction that both increase sensitivity for conventional measurements and allow access to experiments that can investigate and utilize effects associated with strongly interacting spin ensembles and cavities. Superconducting micro-resonators are particularly interesting due to their natural compatibility with low temperatures, where the reduction of thermal noise permits coherent effects of the spin-cavity interaction to be resolved. In this work, we present X-band CW-ESR measurements of a microcrystalline BDPA sample performed using a niobium (Nb) superconducting micro-resonator. The achieved ultimate sensitivity and power conversion factor for this particular device, interfaced with an X-band Bruker EMX Micro ESR spectrometer, were found to be 5.4 × 108 Spins/G and 155 G/W, respectively, at a temperature of 3.8 K. The enhanced spin-cavity interaction in our setup had a profound influence on the measured BDPA spectral line shape, leading to a line-narrowing process not present in measurements performed using a conventional 3D resonator.

How do I remind you? The combined effect of purchase motivation and reminding message content on tourism consumers' verification behavior

Field verification of tourism live-streaming products is related to the ultimate conversion of tourism benefits. Therefore, improving the product verification rate is critical for tourism companies focusing on live-stream marketing. Considering the targeted nature of purchasing tourism live-streaming products, a mechanism model is constructed to form consumer verification behavior based on goal-directed behavior theory, analyzing it through two scenario experiments. When tourism consumers purchase tourism products for promotional purposes, a near-expired discount message can better stimulate their verification behavior; when tourism consumers purchase tourism products for emotional purposes, a limited-time activity message can better stimulate their verification behavior. "Fear of missing out" (FOMO) partially mediated the above interactive relationship, while mental simulation played a moderating role in the primary effect relationship. This study's results emphasize the mechanism of individual decision-making behavior after tourism live-streaming, providing a reference for the online marketing process for tourism companies.

Endoscopic third ventriculostomy with choroid plexus cauterization: predictors of long-term success and comparison with shunt placement for primary treatment of infant hydrocephalus.

Endoscopic third ventriculostomy (ETV) with choroid plexus cauterization (CPC) can avoid ventriculoperitoneal shunt (VPS) dependence in very young hydrocephalic children, although long-term success as a primary treatment in North America has not been previously reported. Moreover, optimal age at surgery, impact of preoperative ventriculomegaly, and relationship to prior cerebrospinal fluid (CSF) diversion remain poorly defined. The authors compared ETV/CPC and VPS placement for averting reoperation, and they evaluated preoperative predictors for reoperation and shunt placement after ETV/CPC. All patients under 12 months of age who underwent initial hydrocephalus treatment via ETV/CPC or VPS placement at Boston Children's Hospital between December 2008 and August 2021 were reviewed. Analyses included Cox regression for independent outcome predictors, and both Kaplan-Meier and log-rank rank tests for time-to-event outcomes. Cutoff values for age and preoperative frontal and occipital horn ratio (FOHR) were determined with receiver operating characteristic curve analysis and Youden's J index. In total, 348 children (150 females) were included with principal etiologies of posthemorrhagic hydrocephalus (26.7%), myelomeningocele (20.1%), and aqueduct stenosis (17.0%). Of these, 266 (76.4%) underwent ETV/CPC and 82 (23.6%) underwent VPS placement. Treatment choice largely reflected surgeon preferences before practice shifted toward endoscopy, with endoscopy not considered for > 70% of initial VPS cases. ETV/CPC patients trended toward fewer reoperations, and Kaplan-Meier analysis estimated that 59% of patients would achieve long-term shunt freedom through 11 years (median 42 months of actual follow-up). Among all patients, corrected age < 2.5 months (p < 0.001), prior temporizing CSF diversion (p = 0.003), and excess intraoperative bleeding (p < 0.001) independently predicted reoperation. Among ETV/CPC patients, corrected age < 2.5 months (p = 0.031), prior CSF diversion (p = 0.001), preoperative FOHR > 0.613 (p = 0.011), and excessive intraoperative bleeding (p = 0.001) independently predicted ultimate conversion to VPS. The actual VPS insertion rates remained low in patients who were ≥ 2.5 months old at ETV/CPC either with prior CSF diversion (2/10 [20.0%]) or without prior CSF diversion (24/123 [19.5%]); however, the actual VPS insertion rates increased in patients who were < 2.5 months old at ETV/CPC with prior CSF diversion (19/26 [73.1%]) or without prior CSF diversion (44/107 [41.1%]). ETV/CPC successfully treated hydrocephalus in most patients younger than 1 year irrespective of etiology, averting observed shunt dependence in 80% of patients ≥ 2.5 months of age regardless of prior CSF diversion and in 59% of those < 2.5 months of age without prior CSF diversion. For infants aged < 2.5 months with prior CSF diversion, particularly those with severe ventriculomegaly, ETV/CPC was unlikely to succeed unless safely delayed.

Investigation of Energy Harvesting Capabilities of Metglas 2605SA1

In the framework of electromechanical energy conversion devices for vibrational energy harvesting, magnetostrictive materials are an attractive alternative solution to the brittleness of piezoelectric materials. Electromagnetic systems have low voltage output at a low frequency while magnetostrictive materials are suitable for a larger frequency bandwidth. In this work, a special experimental emphasis is placed on Fe80Si9B11 (also known as Metglas 2605SA1) alloy. The ultimate energy conversion abilities are investigated by performing experimental Ericsson cycles as well as through theoretical predictions using a dedicated model for the magnetic curves at the material scale. Typical output magnetic energy densities ranged between 0.1 and 1 mJ/cm3/cycle under moderate stress (&lt;100 MPa) and magnetic excitation (up to 4 kA/m). Apart from its energy conversion abilities, Metglas 2605SA1 also features attractive characteristics for realistic applications in microgenerators, such as a low price, which is an important advantage for the mass production and cost-effectiveness of the harvester. Furthermore, its soft magnetic property reduces the need for high magnetic fields and yields a well-adapted solution from a system point of view. It is therefore shown that this material is a suitable conversion material according to the available stress and magnetic excitation magnitudes, in addition to economic considerations.

UV curing behavior of a liquid polyborosilazane and stereolithography to SiBCN ceramic components

The ultraviolet (UV) curing behavior and kinetics both in air and in nitrogen atmosphere of a liquid polyborosilazane were investigated by differential scanning photo calorimeter (DPC) measurement and real-time FTIR techniques. The results showed that the bifunctional acrylic reactive diluent tripropylene glycol diacrylate (TPGDA) content, photo-initiator concentration, and temperature had their optimal values to get the maximum ultimate reaction rate and conversion percentage. It's noteworthy that the addition of TPGDA will greatly enhance polymerization rate and conversion percentage within a very short time-frame. While the rate in air is higher than in nitrogen atmosphere, probably owing to the effect of oxidation curing, which is coordinated with the calculation results of activation energy.Based on the above experiment, we also report on the direct fabrication of SiBCN ceramic components from preceramic polyborosilazanes by stereolithography and subsequent pyrolysis at 900 ○C for 4 h. The TGA curve shows the ceramic yield is 51.1% after pyrolysis at 1200 ○C. A linear shrinkage of 27%, associated with the polymer-to-ceramic conversion, was observable and the density of pyrolyzed SiBCN is about 2 g cm−3 with slight residual porosity. The indentation hardness is 9.83 GPa and the modulus is 77.1 GPa after heat-treatment at 1400 ○C for 3 h.

Ultimate electromechanical energy conversion performance and energy storage capacity of ferroelectric materials under high excitation levels

In the framework of piezoelectric energy harvesting, this work focused on the quantification of the ultimate energy conversion capability of various ferroelectric ceramics and single crystals. Energy conversion was achieved by the application of Ericsson cycles under high electric field and mechanical stress. The main aim of this approach was to experimentally apply the electromechanical Ericsson cycles on several key materials. This process was decomposed into four steps, which consisted of applying and removing an electric field under constant stress and stress application/removal under a constant electric field. In this work, ferroelectric ceramics—hard PZT C203, medium PZT C6, soft PZT C9, and single crystal PMN-25PT and PZN-8PT—and paraelectric ceramic PMN 15 were tested. The PMN-25PT and PZN-8PT ferroelectric single crystals exhibited higher energy conversion potential than the ceramics in the ferroelectric and paraelectric phases. However, the soft PZT C9 ceramic (107.6 mJ/cm3) was comparable to single crystal PMN-25PT (118.7 mJ/cm3). Considering the cost and fabrication process, PZT C9 is an excellent candidate for practical applications. A simple yet accurate experimental estimation of the energy density of the materials based on the bipolar hysteresis curves under compressive stresses of 1 and 100 MPa was also proposed. The estimated energy densities were similar to the real Ericsson cycles. The energy storage capacity of these materials was also analyzed. The PMN 15 ceramic in the paraelectric phase had the highest stored energy, and in the paraelectric phase, PMN 15 had a maximum stored electrical energy of 87 mJ/cm3 under a static stress value of 1 MPa, which was increased to 105 mJ/cm3 under a static stress value of 100 MPa. Ultimately, this study allowed for the evaluation of the maximal energy conversion capabilities of several classes of electroactive materials, highlighting their potential in terms of their target applications and operative environments (such as the maximal stress or electric field).

Novel Process for Butyl Acetate Production via Membrane Reactor: A Comparative Study with the Conventional and Reactive Distillation Processes

Butyl acetate (BuAc) is widely used as a solvent in many applications, mainly in the food and pharmaceutical industries. The conventional process for BuAc production is both capital and energy intensive. The purification process involves the separation of BuAc from the azeotropic mixture of water and n-butanol, which is difficult to accomplish using a simple distillation unit. In this study, a membrane reactor (MR) for BuAc production via the esterification of n-butanol was investigated. The MR using the Amberlyst-15 catalyst was modeled and validated with previously reported experimental data, and a good agreement was achieved. The ultimate conversion of n-butanol using the MR was 92.0%, compared to 69.8% for the conventional reactor. This study is the first to propose an intensified MR-based process for butyl acetate production. The MR-based process was developed and rigorously simulated using Aspen Plus for an annual plant capacity of 92,500 metric tons of BuAc. The MR-based process is environmentally friendly regarding CO2 emissions, with a reduction of 80% compared to the conventional process. The economic analysis of the MR-based process shows a payback period of 2.7 years and a return on investment (ROI) of 23.1%. The MR-based process for BuAc production is a promising technology that provides similar key benefits as compared to the reactive distillation (RD) process.

Development and Intensification of the Ethylene Process Utilizing a Catalytic Membrane Reactor.

Ethylene is considered the most important petrochemical constituent in the world today. It is currently produced via the thermal cracking process, which is generally expensive. Ethane dehydrogenation (EDH) is endothermic, and the thermodynamic equilibrium limits its conversion. The present study explores the viability of using a catalytic membrane reactor (MR) for ethylene production from EDH. The removal of hydrogen from the reaction zone using a palladium–silver (Pd–Ag) membrane has led to a high shift in the equilibrium conversion. The effects of operating conditions and reactor configurations on the ethane conversion were investigated. The ultimate ethane conversion was 22.2% when using the MR at 660 K and 300 kPa. The ethane conversion in the shell-side of the reactor increased to ∼99% when benzene hydrogenation was added as an auxiliary reaction in the tube-side of the reactor. Two new processes for ethylene production were developed for an annual capacity of 100,000 metric tons. Cryogenic distillation was required to separate ethylene from ethane if there is no auxiliary reaction. On the other hand, the ethylene process with cyclohexane as a byproduct does not require a refrigeration cycle system, and its economic analysis shows a return on investment of 34.4%, indicating that the process is a promising technology.

Machine Learning Approach to Delineate the Impact of Material Properties on Solar Cell Device Physics.

In this research, solar cell capacitance simulator-one-dimensional (SCAPS-1D) software was used to build and probe nontoxic Cs-based perovskite solar devices and investigate modulations of key material parameters on ultimate power conversion efficiency (PCE). The input material parameters of the absorber Cs-perovskite layer were incrementally changed, and with the various resulting combinations, 63,500 unique devices were formed and probed to produce device PCE. Versatile and well-established machine learning algorithms were thereafter utilized to train, test, and evaluate the output dataset with a focused goal to delineate and rank the input material parameters for their impact on ultimate device performance and PCE. The most impactful parameters were then tuned to showcase unique ranges that would ultimately lead to higher device PCE values. As a validation step, the predicted results were confirmed against SCAPS simulated results as well, highlighting high accuracy and low error metrics. Further optimization of intrinsic material parameters was conducted through modulation of absorber layer thickness, back contact metal, and bulk defect concentration, resulting in an improvement in the PCE of the device from 13.29 to 16.68%. Overall, the results from this investigation provide much-needed insight and guidance for researchers at large, and experimentalists in particular, toward fabricating commercially viable nontoxic inorganic perovskite alternatives for the burgeoning solar industry.

Sb2 Se3 Thin-Film Solar Cells Exceeding 10% Power Conversion Efficiency Enabled by Injection Vapor Deposition Technology.

Binary Sb2 Se3 semiconductors are promising as the absorber materials in inorganic chalcogenide compound photovoltaics due to their attractive anisotropic optoelectronic properties. However, Sb2 Se3 solar cells suffer from complex and unconventional intrinsic defects due to the low symmetry of the quasi-1D crystal structure resulting in a considerable voltage deficit, which limits the ultimate power conversion efficiency (PCE). In this work, the creation of compact Sb2 Se3 films with strong [00l] orientation, high crystallinity, minimal deep level defect density, fewer trap states, and low non-radiative recombination loss by injection vapor deposition is reported. This deposition technique enables superior films compared with close-spaced sublimation and coevaporation technologies. The resulting Sb2 Se3 thin-film solar cells yield a PCE of 10.12%, owing to the suppressed carrier recombination and excellent carrier transport and extraction. This method thus opens a new and effective avenue for the fabrication of high-quality Sb2 Se3 and other high-quality chalcogenide semiconductors.

Establishment of a Quantitative Time Conversion Relationship Between Laboratory Accelerated Weathering Aging and Outdoor Natural Aging of the High-Content Polymer Modified Asphalt Applied in Porous Asphalt Pavement: From Theory to Experiment

The purpose of this study was to determine the quantitative time conversion relationship between indoor accelerated weathering aging (AWA) and outdoor natural aging of the high-content polymer modified asphalt (HCPMA) applied in porous asphalt pavement from both theoretical and experimental aspects. Firstly, the calculated aging acceleration rate of the AWA test was determined based on orthogonal analysis and chemical reaction kinetics. The indoor AWA test (0–12 days) and outdoor natural aging (0–12 months) were then performed on HCPMA, and the dynamic shear rheology test and multiple stress creep recovery test were conducted to investigate the rheological properties of HCPMA. Furthermore, the measured aging acceleration rate of the AWA test was determined according to rheological index comparison and then compared with the calculated aging acceleration rate to obtain the ultimate time conversion relationship between indoor and outdoor aging. Results show that it is practical to simulate the natural aging by using the AWA test. HCPMA exhibits similar changes in macroscopic rheological properties in indoor AWA and outdoor natural aging. According to the comparison of rheological indexes, the measured aging acceleration rate of HCPMA under the harshest aging condition is 57.5–120, which is basically consistent with the calculated aging acceleration rate (66) by the chemical reaction kinetics. This further demonstrates the feasibility of this study for determining the indoor-outdoor aging time conversion relationship from theoretical and experimental aspects.

Quaternary Organic Solar Cells Enable Suppressed Energy Loss

Multi‐component organic solar cells (OSCs) composing of more than two donor and acceptor materials have attracted increasing attention, due to the possibilities to further mitigate voltage loss (ΔVoc) for the gain of open‐circuit voltage (Voc). However, the control of phase morphology in multi‐component blend systems that critically impacts ΔVoc and the ultimate power conversion efficiency (PCE) is still a challenge. Here, we report a quaternary blend‐based strategy for non‐fullerene OSCs by using two polymer donors (PM6 and L20) along with acceptors of a non‐fullerene (Y6) and PC71BM, leading to concurrent improvements of the Voc, device fill factor and eventual PCE. The quaternary OSC exhibits the advantages of a higher charge collection efficiency, expedited charge carrier sweep‐out, and reduced charge recombination losses. The suppression on ΔVoc is attributed to the reduced radiative recombination loss below the bandgap (0.143 V) and non‐radiative voltage loss (0.216 V). These properties are linked to synergies of modified energetics and film morphology of the quaternary blends. This work demonstrates that incorporating suitable donor and acceptor guest molecules to organic binary blend systems is a highly viable approach for lowering the energy loss in organic bulk heterojunctions towards the boost of photovoltaic performance for realistic energy conversion applications.

Charge transfer of carbon nanomaterials for efficient metal‐free electrocatalysis

AbstractRecently, carbon‐based metal‐free electrocatalysts (C‐MFECs) have drawn considerable research attention because of their attractive physicochemical characteristics, cost‐effectiveness, and ability to convert and store energy efficiently. Efficient intramolecular charge transfer among different parts of the carbon electrocatalyst and/or intermolecular charge transfer between electrocatalyst and electrolyte dictate the ultimate energy conversion performance. Experimental results and theoretical analyses have demonstrated that rational design of metal‐free carbon nanomaterials, coupled with proper intramolecular charge transfer through heteroatom doping, incorporation of Stone–Wales defects, and/or intermolecular charge transfer through adsorption of appropriate molecules/moieties, can promote efficient electrocatalysis. In this article, we will first provide the related theoretical principles and then present an overview on the rational design and development of C‐MFECs for efficient charge transfer, followed by elucidating charge‐transfer processes for different electrocatalytic reactions related to renewable energy conversion and environmental remediation technologies. Finally, the current challenges and future perspectives in this exciting field will be discussed.

Electron-hole pair creation and conversion efficiency in radioisotope microbatteries

The ultimate conversion efficiency of semiconductor radioisotope microbatteries is set by the average energy consumed in the creation of an electron-hole pair, ω. Although the Klein relationship between ω and semiconductor bandgap, Eg, is widely cited, not only for radioisotope microbatteries, but indeed for a multitude of fields requiring accurate values of ω, its validity has been recently questioned; new experimental measurements have resulted in the refined Bertuccio-Maiocchi-Barnett (BMB) relationship. Here, it is shown that the new relationship indicates the ultimately achievable conversion efficiencies of radioisotope microbatteries are much greater than had ever been expected. For example, it appears possible to produce planar 63Ni-Diamond radioisotope microbatteries with output powers 130× greater than has currently been achieved. The ultimate limit for batteries employing pore channels rather than planar designs is likely to be even greater still. These new findings open the possibility of using radioisotope microbatteries in a far greater variety of applications than has been traditionally assumed. As well as being of direct applicability to radioisotope microbatteries, the results highlight the need to reconsider the use of the Klein relationship in all fields that currently employ it.

Synthesis and Properties of Aromatic-Terminated Diacetylene Organogelators and Their Application to Photopatterning of Polydiacetylenes.

A series of simply structured diacetylene-diamide-based gelators (DAGs) with aromatic terminals were synthesized, and their gelation and subsequent photopolymerization abilities were analyzed. DAGs with an adequate spacer length (n) and tolyl terminals (DA-Tn) interacted with aromatic solvents, such as benzene and xylenes, at elevated temperatures. During the subsequent cooling process, the DAGs interacted with each other through CH-π interactions at their terminal positions. They also formed one-dimensional hydrogen bonding arrays through secondary amides, leading to stable organogels. These gels polymerized into π-conjugated polydiacetylenes (PDAs) under ultraviolet irradiation. In the p-xylene gels of DA-Tn, the spacer length exerted characteristic odd-even effects on the photopolymerization rates over a certain range (n = 3-6), which can be explained by periodic changes in the uniformity of the molecular packing modes. When the gelling solvent was changed to cyclohexane, the gelation and photopolymerization abilities were greatly improved because the DA-Tn gel networks became highly crystallized and transparent to ultraviolet light (254 nm). The ultimate conversion to PDA from DA-T8/cyclohexane gels was 45.2 wt %. Applying photolithographic techniques to the DAG with excellent photopolymerizability in the film state, we successfully fabricated microscale photopatterns of PDA. We also established a convenient removal process (development process) of DA monomers in unexposed areas. The resulting PDA patterns were quite stable to ambient light stimuli.

Ultimate conversion efficiency of second harmonic generation in all-dielectric resonators of quasi-BICs in consideration of nonlinear refraction of dielectrics

We investigate second harmonic generation (SHG) in all-dielectric resonance nanostructures of high-Q factors assisted by quasi-bound states in the continuum (quasi-BICs). The typical resonators, e.g., guided-mode resonance gratings and asymmetric metasurfaces, fabricated by AlGaAs were numerically studied with the consideration of nonlinear refraction of AlGaAs. The resonance peak and line-shape of linear transmission and SHG spectra in the resonators can be dramatically changed under intense pump intensities. The SHG conversion efficiency in the nanostructures working at quasi-BICs is much lower than the traditionally expected values without considering the nonlinear refraction of dielectrics. The ultimate SHG conversion efficiency is finally obtained. The investigation has the significance for the design and understanding of efficient nonlinear metasurfaces of high-Q factors.

Design and Simulation Studies of Hybrid Power Systems Based on Photovoltaic, Wind, Electrolyzer, and PEM Fuel Cells

In recent years, the need to reduce environmental impacts and increase flexibility in the energy sector has led to increased penetration of renewable energy sources and the shift from concentrated to decentralized generation. A fuel cell is an instrument that produces electricity by chemical reaction. Fuel cells are a promising technology for ultimate energy conversion and energy generation. We see that this system is integrated, where we find that the wind and photovoltaic energy system is complementary between them, because not all days are sunny, windy, or night, so we see that this system has higher reliability to provide continuous generation. At low load hours, PV and electrolysis units produce extra power. After being compressed, hydrogen is stored in tanks. The purpose of this study is to separate the Bahr AL-Najaf Area from the main power grid and make it an independent network by itself. The PEM fuel cells were analyzed and designed, and it were found that one layer is equal to 570.96 Watt at 0.61 volts and 1.04 A/Cm2. The number of layers in one stack is designed to be equal to 13 layers, so that the total power of one stack is equal to 7422.48 Watt. That is, the number of stacks required to generate the required energy from the fuel cells is equal to 203 stk. This study provided an analysis of the hybrid system to cover the electricity demand in the Bahr AL-Najaf region of 1.5 MW, the attained hybrid power system TNPC cost was about 9,573,208 USD, whereas the capital cost and energy cost (COE) were about 7,750,000 USD and 0.169 USD/kWh respectively, for one year.

Ultraselective Monovalent Metal Ion Conduction in a Three-Dimensional Sub-1 nm Nanofluidic Device Constructed by Metal-Organic Frameworks.

Construction of nanofluidic devices with an ultimate ion selectivity analogue to biological ion channels has been of great interest for their versatile applications in energy harvesting and conversion, mineral extraction, and ion separation. Herein, we report a three-dimensional (3D) sub-1 nm nanofluidic device to achieve high monovalent metal ion selectivity and conductivity. The 3D nanofluidic channel is constructed by assembly of a carboxyl-functionalized metal-organic framework (MOF, UiO-66-COOH) crystals with subnanometer pores into an ethanediamine-functionalized polymer nanochannel via a nanoconfined interfacial growth method. The 3D UiO-66-COOH nanofluidic channel achieves an ultrahigh K+/Mg2+ selectivity up to 1554.9, and the corresponding K+ conductivity is one to three orders of magnitude higher than that in bulk. Drift-diffusion experiments of the nanofluidic channel further reveal an ultrahigh charge selectivity (K+/Cl-) up to 112.1, as verified by the high K/Cl content ratio in UiO-66-COOH. The high metal ion selectivity is attributed to the size-exclusion, charge selectivity, and ion binding of the negatively charged MOF channels. This work will inspire the design of diverse MOF-based nanofluidic devices for ultimate ion separation and energy conversion.