Energy Production Applications Research Articles

Modified Titanium Dioxide Nanoparticles for Photocatalytic Splitting of Water and Its Application in Environmental Remediation as a Potential Alternative

Herein we reviewed Titanium dioxide (TiO2) nanoparticles and how they are applied in the photocatalytic splitting of water to generate hydrogen but also to remove both organic and inorganic pollutants. Hydrogen generation through the splitting of water by TiO2 which is a cheap, efficient, and non-toxic photocatalyst has found wide application in clean energy production. The efficiency of the photocatalyst can be improved by using water or sacrificial agents as electron donors, thereby enhancing hydrogen production. In addition, this review explores the fundamental principles, mechanisms, and applications of TiO2-based photocatalysis. It further, highlights the structural properties, bandgap engineering, and surface modifications that influence the catalytic activity of TiO2. Additionally, we discuss the doping of TiO2 with both metals and non-metals to narrow the energy band gap which lowers the recombination effects. Finally, it introduces the potential applications of TiO2-based photocatalysis in the photodegradation of organic and inorganic pollutants.

Tailoring of Time for Hydrothermal Synthesis of 2D MoSe2 with Enhanced Adsorption and Electro‐Catalytic Efficiency for Applications in Self‐Cleaning and Hydrogen Energy Generation

AbstractMolybdenum diselenide (MoSe2), a 2D layered transition metal dichalcogenide, has garnered significant scientific research interest for its catalytic and electrocatalytic activities. Here, a straightforward hydrothermal procedure is used to synthesize MoSe2 nanosheets (NSs) and focus on their adsorption capabilities and hydrogen evolution reaction (HER) activity. The MoSe2 NSs which are synthesized by 12 h of hydrothermal treatment found to exhibit the highest adsorption capacity of 91.67 mg g−1. The kinetics of the adsorption process have been found to follow the pseudo‐second‐order model, signifying chemisorption and multilayer adsorption as described by the Freundlich isotherm. The thermodynamic analysis further suggests that the adsorption proceeds by endothermic and spontaneous mechanisms. The self‐cleaning property of the adsorbent is demonstrated by degrading the dye on the adsorbent‐coated cotton fabric. The sample created using a 12 h hydrothermal method has been shown to have a minimal Tafel slope of 58 mV dec−1. It also shows excellent HER activity at low over‐potential and possesses long‐term durability. The dual functionality of MoSe2 NSs in both adsorption and electrocatalytic activity highlights their potential for application in environmental remediation and renewable energy production.

Sewage sludge as soil amendment in arid soils - A trace metal, nutrient and trace organics perspective

Sewage sludge management has emerged as a critical environmental challenge due to the large volumes generated globally. Valorization techniques, including energy production and agricultural applications, offer sustainable solutions, particularly in regions with low soil fertility. The sewage sludge utilization in the Middle East region is low. This paper presents a pragmatic risk-based assessment using the risk-based corrective action approach to evaluate sludge application in desert soils. This methodology focuses on the source-pathway-receptor interaction and assesses the likelihood of contaminants posing a real threat. In arid desert regions like Kuwait, where soil organic content and moisture are extremely low, the application of sewage sludge presents a feasible option to enhance soil quality and valorize unutilized sludge dumps which pose significant environmental concerns but are left to desiccate in the absence of any environmental regulation towards its utilization and due to religious apprehensions. Since the sludge characterization is not well detailed a brief review of the available data was included to establish the bounds of various organic, metal and nutrients that were used for generating the model. This study examines the changes in the physico-chemical properties of desert soils following sludge application, focusing on the likely fate of trace metals and organic contaminants. The alkaline desert soils of Kuwait, with a pH range of 7.7–8.9, are particularly suitable for sludge application due to the low mobility of metals in alkaline conditions. Additionally, sludge application lowers soil pH, improving conditions for plant growth. The region's deeper water table and scant annual precipitation (<0.15 m) further reduce the risk of groundwater contamination and deeper soil profile contamination. The presence of organic content, nitrates, Zn, and Cu in sludge can promote native vegetation growth. However, trace organic contaminants, including PAHs, PCBs, and pharmaceuticals, pose a potential risk to soil contamination, but since the geological section shows intervening impervious layers the contamination is going to be localized, even if there is sufficient leachable fraction. Given the minimal risk of contamination under the unique conditions of arid regions, this approach highlights the potential for eco-friendly sludge valorization, that will improve vegetation cover and arrest the suspended particulate suspension. However, before the large-scale implementation of this modelled concept, a detailed experimental study on the pilot scale or lysimeters is recommended to assess the long-term impacts of sludge application and to obtain data that can inform policy guidelines for sustainable sludge management in desert environments.

A parametric similarity measure for neutrosophic set and its applications in energy production

As a useful tool for managing ambiguous and inconsistent data, the Single Value Neutrosophic Set (SVNSs) is an extension of both Fuzzy Sets (FSs) and Intuitionistic Fuzzy Sets (IFSs). In the field of information theory, metrics like similarity, entropy, and distance are important. Although a number of entropy measures for SVNSs have been put forth and used in real-world situations, both academic research and real-world applications have pointed out certain drawbacks. Additionally, the Similarity Measures (SMs) is a useful instrument for determining how similar any two fuzzy values are to one another. The distance between the values allows the current SMs to evaluate the similarity. However, due to a few characteristics and intricate value operations, there are irrational and nonsensical cases. To deal with these preposterous cases, this paper proposed a parametric similarity measure in view of three parameters m1,m2,m3 in which decision makers can obtain the appropriate SMs by changing parameters with different decision styles. Furthermore, we analyze some existing SMs from a mathematical perspective and demonstrate the success of the proposed SMs using mathematical models. Ultimately, we apply the suggested SMs to resolve the Multi-Attribute Decision-Making (MADM) problems. We learn from the correlation and analysis that the suggested SM outperforms certain other SMs that are based on the SVNSs.

Metal-doped amorphous microporous carbon for isotope separation: Pore size modulation and selective deuterium adsorption

Efficient hydrogen isotope separation is crucial for applications in energy production and advanced scientific research, but separation of these poses significant challenges. In this study, we developed amorphous microporous carbon (AMC) derived from a zeolite template and explored hydrogen isotope separation using quantum sieving. Thermal desorption spectroscopy (TDS) technique was used to evaluate the selectivity of hydrogen (H2) and deuterium (D2) isotope separation. The doping of metal ions, such as Ca2⁺, Mg2⁺, Ni2⁺, and Cu2⁺, in the porous carbon modulates the physicochemical properties of the pores. The metal-doped carbon samples demonstrated D2vs H2 selectivity (SD2/H2) of over 10, compared to the pristine carbon's SD2/H2 of less than 8. Density functional theory (DFT) calculation infers that pore modulation through metal doping enhanced the binding affinity of materials towards D2 resulting in increased separation selectivity compared to pristine carbon samples. This approach not only boosts separation efficiency but also provides a scalable and cost-effective solution for industrial applications.

NaNbO3 Nanocubes: Perovskite Catalysts for Methanol Polymerization

Polyoxymethylene dimethyl ethers (PODEs) are a class of oxygenated fuels with promising applications in energy production and emission reduction. They are often utilized as a diesel fuel additive or substitute, which reduces the formation of harmful emissions such as polycyclic aromatic hydrocarbons (PAH), soot, nitrogen oxides (NOx), and carbon monoxide (CO). The oxidative polymerization of methanol presents a promising route for the formation of PODEs. NaNbO3, a type of perovskite oxide, was synthesized with a well-defined nanocubic structure through solvothermal synthesis using a Nb2O5 precursor. The catalytic potential of both the NaNbO3 nanocubes and the well-studied Nb2O5 precursor was assessed for the oxidative polymerization of methanol into PODEs. NaNbO­3 demonstrated catalytic performance comparable to Nb2O5 as both catalysts produced formaldehyde and dimethyl ether, which are precursors to PODE. Powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy, and Brunauer-Emmett-Teller (BET) surface area confirmed the crystalline nature and desired cubic morphology of the NaNbO3 nanocubes. Additionally, Nb2O5 precursors with an orthorhombic, as opposed to a monoclinic or hexagonal crystal system were determined to produce NaNbO3 nanocubes successfully. Effective shape control of the NaNbO3 nanocubes makes this catalyst an intriguing material to understand and apply in heterogenous catalysis.

Water, energy, and food nexus in a solar-powered brackish water desalination plant in Jordan

Abstract The growing demand for water in domestic, agricultural, and energy production applications poses a significant challenge for Jordan. This work assesses the role of brackish water desalination as an alternative to alleviate water scarcity in semi-arid regions. Desalination is still limited in its application in Jordan due to high electricity tariffs. Shifting to renewable sources such as solar energy, abundant in the country, is a feasible way to power technologies with a high energy demand. In this work, we study the brackish water desalination plant at the Hashemite University in Jordan that is powered by a photovoltaic (PV) solar system (the HU PV-BWRO). The plant’s performance was evaluated in the context of the water-energy nexus as a hybrid water supply solution. While this work integrates essential elements, such as water availability, technical options, economic viability, and agricultural management, the analysis primarily focuses on the technical and economic aspects related to water, energy, and food. Water assessment results indicate that the groundwater wells near the HU campus are at risk of quality degradation over time, as they have shown a slight increasing trend in salinization from 2015 to 2023. Energy assessment results show a promising performance from the HU PV-BWRO desalination plant, with a specific energy consumption (SEC) value of 1.2 kWh m−3 (140% to 400% less energy consumption compared with other Jordanian desalination plants of similar capacity). Unit price comparisons indicate that the energy cost of PV (0.042 USD/m3) is 5 times less than the cost of grid electricity (0.24 USD/m3). The operational cost of the solar desalination plant at full capacity, is USD 0.23/m3. This is about 260% less than the operation cost for local, grid-powered desalination plants. Finally, it is estimated that by operating the plant at 50% of its total capacity, the produced water could be sufficient to irrigate up to 80% of the HU campus to increase agricultural production. This study highlights the importance of decreasing reliance on energy for water and food production, and it shows that the use of solar powered desalination could be used as an example in semi-arid regions, particularly in terms of integrating renewable energy and energy efficiency.

Bioderived nanostructure and their functional contribution in immobilization of cellulolytic enzymes for improving biosensing application

Cellulases fall under the biocatalyst and one of industrial enzymes which is highest in demand due to diverse and huge applications. It plays major role in cellulosic bioenergy production achieving biomass hydrolysis for sugar and energy production. Inspite of prime enzyme in demand and key application in cellulosic energy production, this group of enzymes are suffering with lower enzyme activity and poor functional stability which directly influence the poor bioconversion efficiency of cellulosic biomass and bioenergy production. This is one the crucial issue which blocks the suitable commercial implementation of bioenergy at global scale. Therefore, researches in this particular area accelerate and speed in up to improve the functional stability of this enzymes. Immobilization of cellulolytic enzymes on nanomaterials is emerging as one of the very promising approaches in this area and supposed to have sustainable future towards improving the functional stability of cellulase enzymes via nanostructure based immobilization. Due to unique physicochemical properties and mode of origin nanoform, these nanomaterials can be an effective tool to enhance the catalytic stability of the cellulase enzymes. Therefore, the present reviews explore the possibilities of immobilization of nanomaterials as one of the promising tool to improve cellulosic bioenergy production. Additionally, one of the prime focus of the review is also based on the types, methods and mode of immobilization using different nanomaterials and analyzed the existing advantages and disadvantages of the process. Moreover, the work has also been highlighted the existing limitation and the future suggestion to improve the process applicability.

Hydrothermal approach for the synthesis of FeSe2/Ti3CNTx and its applications towards water splitting and energy storage

Different materials were used for energy production and energy storage applications. In this study, MXene was combined with FeSe2 to develop a novel and efficient catalyst. FeSe2/Ti3CNTx was used for water splitting as well as energy storage. HER and OER were performed to find out its efficiency for water splitting. The overpotential observed by the material is 317.18 mV for HER and 309 mV for OER with a Tafel slope of 149.15 mV.dec−1 and 2.47 mV.dec−1 respectively. In symmetrical system testing for water splitting using two-electrode cell, a potential difference of 1.54 mV was observed. Observing the behavior towards water splitting, synthesized material is also tested for energy storage to fulfill the era's demand. Capacitance was determined at different current densities and 232 F.g−1 specific capacitance was observed at the current densities of 0.5 A.g−1. Good capacity retention was observed and after 170 cycles columbic efficiency became constant which remained constant till 1000 cycles. This approach leads to a new way towards green energy production as well as energy storage.

Polychloride and benzene ring synergistically boosting photocatalytic degradation and nitrogen fixation performances of carbon nitride

The limited active site exposure, insufficient light absorption and poor charge behavior of carbon nitride (CN) limit its application in environmental remediation and clean energy production. In this study, ultrathin porous CN with enhanced photocatalytic activity was constructed by doping 2,2′,5,5′-Tetrachlorobenzidine (TB) into CN framework. The synergistic effect of polychloride and benzene rings on CN leads to the significant enhancement of range/intensity of visible-light harvest and charge behavior, as well as specific surface area. The optimal sample achieves 100% tetracycline photodegradation efficiency with a rate constant approximately 9 times of pristine CN, and total organic carbon removal efficiency reaches 78.2%. Moreover, photocatalytic ammonia production rate is 7 times of pristine CN. Through active species trapping experiments, ESR, LC-MS, toxicity prediction and DFT calculations, the main active species, degradation pathway, intermediates toxicity and enhanced mechanism of photocatalytic activity are investigated. This work provides a reference for simultaneously regulating the morphology, light absorption and charge behavior of CN-based photocatalyst for addressing environmental and energy concerns.

MFe2O4 (M: Cu, Ni)/SnS2magnetic Core-Shell Heterostructure for Photocatalytic H2 Generation and Environmental Remediation

Overgrowing demand for sustainable energy sources and environmental remediation has driven extensive research in the field of photocatalysis. This study presents a hydrothermal synthesis of a novel MFe2O4 (M: Cu, Ni)/SnS2 magnetic core-shell heterostructure. The engineered heterostructure combines the unique properties of MFe2O4 (M: Cu, Ni) magnetic crystal as a core with SnS2 nanosheets as a shell, aiming to exploit type-2 heterojunction properties to improve effects for improved photocatalytic performance. The structural chemistry, phase formation, and crystal orientation of the prepared material are investigated using various analytical techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman, and FTIR Spectroscopy. FE-SEM analysis reveals a well-defined core-shell morphology with intimate interfaces between MFe2O4 (M: Cu, Ni) crystals and SnS2 nanosheets. Photocatalytic efficiency is assessed through the industrial dye degradation process. The influence of the heterostructure's structural features on the photocatalytic activity is explored through density function theory, emphasizing the role of the core-shell interface and the magnetic properties of MFe2O4 (M: Cu, Ni) cores. The chemistry between the magnetic core and the shell in the heterostructure is demonstrated to be crucial for optimizing charge carrier dynamics and promoting surface reactions. Photocatalytic H2 generation under artificial simulated sunlight irradiation in the presence of MFe2O4 (M: Cu, Ni)/SnS2 core-shell heterostructure is demonstrated. This study not only presents a novel MFe2O4 (M: Cu, Ni)/SnS2 heterostructure for photocatalytic H2 generation but also provides valuable insights into the intricate relationship between structural chemistry and photocatalytic efficiency. The engineered heterostructure shows promising potential for applications in sustainable energy production and environmental remediation, contributing to the ongoing efforts towards a cleaner and more sustainable future.

Materials-driven strategies in bacterial engineering.

This perspective article focuses on the innovative field of materials-based bacterial engineering, highlighting interdisciplinary research that employs material science to study, augment, and exploit the attributes of living bacteria. By utilizing exogenous abiotic material interfaces, researchers can engineer bacteria to perform new functions, such as enhanced bioelectric capabilities and improved photosynthetic efficiency. Additionally, materials can modulate bacterial communities and transform bacteria into biohybrid microrobots, offering promising solutions for sustainable energy production, environmental remediation, and medical applications. Finally, the perspective discusses a general paradigm for engineering bacteria through the materials-driven modulation of their transmembrane potential. This parameter regulates their ion channel activity and ultimately their bioenergetics, suggesting that controlling it could allow scientists to hack the bioelectric language bacteria use for communication, task execution, and environmental response.

Innovative sanitation solutions: evaluating the performance of faecal sludge treatment plant in humanitarian settings: A case study from Rohingya camps in Bangladesh

The Rohingya crisis has precipitated one of the most significant humanitarian emergencies, resulting in over 900,000 refugees residing in Cox's Bazar, Bangladesh. The rapid influx of refugees has posed substantial challenges in providing essential services, particularly sanitation, in a densely populated and resource-constrained environment. This study examines the performance of faecal sludge treatment plants (FSTPs) implemented in the Rohingya camps, focusing on key performance indicators such as treatment efficiency, operational challenges, health outcomes, and resource recovery potential. Analysis reveals that FSTPs have played a crucial role in reducing pathogen levels in treated sludge, thereby mitigating the risk of waterborne diseases and environmental contamination. Despite these successes, operational challenges such as frequent desludging, infrastructure maintenance, and the logistical complexities of waste collection and transport persist. The study highlights the importance of addressing these challenges through regular maintenance, infrastructure upgrades, and innovative logistical solutions. Health outcomes have shown improvement with a reduction in sanitation-related diseases, underscoring the health benefits of effective FSTP implementation. Additionally, resource recovery from treated sludge presents a sustainable approach, with potential applications in agriculture and energy production. Community engagement has emerged as a critical factor in the success of these interventions. Effective community involvement in the planning, implementation, and maintenance of sanitation facilities has been instrumental in ensuring their acceptance and proper use. The study emphasizes the need for continued community education and participation to sustain these benefits. In conclusion, while FSTPs have significantly improved sanitation conditions in the Rohingya camps, ongoing efforts are required to enhance operational efficiency, address logistical challenges, and foster community involvement. The findings provide valuable insights for the design and implementation of innovative sanitation solutions in similar humanitarian settings worldwide.

Innovative Solution for Invasive Species and Water Pollution: Hydrochar Synthesis from Pleco Fish Biomass

In recent years, the invasive pleco fish has emerged as a global concern due to its adverse effects on ecosystems and economic activities, particularly in various water bodies in Mexico. This study introduces an innovative solution, employing microwave-assisted hydrothermal carbonization (MHTC) to synthesize hydrochar from pleco fish biomass. The research aimed to optimize synthesis conditions to enhance hydrochar yield, calorific value, and adsorption capacities for fluoride and cadmium in water. MHTC, characterized by low energy consumption, high reaction rates, and a simple design, was employed as a thermochemical process for hydrochar production. Key findings revealed that through response surface analysis, the study identified the optimal synthesis conditions for hydrochar production, maximizing yield and adsorption capacities while minimizing energy consumption. Physicochemical characterization demonstrated that hydrochars derived from pleco fish biomass exhibited mesoporous structures with fragmented surfaces, resembling hydroxyapatite, a major component of bone. Hydrochars derived from pleco fish biomass exhibited promising adsorption capacities for fluoride and cadmium in water, with hydrochar from Exp. 1 (90 min, 160 °C) showing the highest adsorption capacity for fluoride (4.16 mg/g), while Exp. 5 (90 min, 180 °C) demonstrated superior adsorption capacity for cadmium (98.5 mg/g). Furthermore, the utilization of pleco fish biomass for hydrochar production not only offers an eco-friendly disposal method for invasive species but also addresses fluoride and cadmium contamination issues, contributing to sustainable waste management and water treatment solutions. The resulting hydrochar, rich in solid fuel content with low pollutant emissions, presents a promising approach for waste management and carbon sequestration. Moreover, the optimized synthesis conditions pave the way for sustainable applications in energy production, addressing critical environmental and public health concerns. This research provides valuable insights into the potential of microwave-assisted hydrothermal carbonization for transforming invasive species into valuable resources, thereby mitigating environmental challenges and promoting sustainable development.

Numerical simulation of Buongiorno's model on Maxwell nanofluid with heat and mass transfer using Arrhenius energy: a thermal engineering implementation

The thermal features of nanoparticles owing to progressive mechanisms are a fascinating phenomenon due to their applications in energy production, cooling procedures, heat transmission devices. Therefore, in the present study, the magnetohydrodynamic combined convection of Maxwell nanofluid and characteristics of heat transport in the presence of thermal radiation with a nonlinear relationship for modifications in the energy equation have been examined. Moreover, the features of activation energy in the presence of swimming microorganisms are considered. For motivation, the influence of bioconvection, magnetic field, and thermophoresis with convective boundary conditions are part of this investigation. The governing PDEs connected with momentum, energy, concentration, and density are converted into ODEs by using similarity functions. A transformed, dimensionless, nonlinear set of ODEs is tracked via a shooting scheme. The numerical results of prominent parameters have been analyzed in the form of graphs and tables using the computational software MATLAB. A significance improvement in the velocity profile is noted for the increasing value of Maxwell parameter. With rise of mixed convection parameter, both energy and volumetric friction field deteriorated. The determination of Biot number that is associated with the coefficient of heat transfer is more effective for growing the temperature and volumetric friction distribution. These conclusions may be appreciated in improving the efficiency of heat transfer strategies.

Beyond methane, new frontiers in anaerobic microbial hydrocarbon utilizing pathways.

Alkanes, single carbon methane to long-chain hydrocarbons (e.g. hexadecane and tetradecane), are important carbon sources to anaerobic microbial communities. In anoxic environments, archaea are known to utilize and produce methane via the methyl-coenzyme M reductase enzyme (MCR). Recent explorations of new environments, like deep sea sediments, that have coupled metagenomics and cultivation experiments revealed divergent MCRs, also referred to as alkyl-coenzyme M reductases (ACRs) in archaea, with similar mechanisms as the C1 utilizing canonical MCR mechanism. These ACR enzymes have been shown to activate other alkanes such as ethane, propane and butane for subsequent degradation. The reversibility of canonical MCRs suggests that these non-methane-activating homologues (ACRs) might have similar reversibility, perhaps mediated by undiscovered lineages that produce alkanes under certain conditions. The discovery of these alternative alkane utilization pathways holds significant promise for a breadth of potential biotechnological applications in bioremediation, energy production and climate change mitigation.

CNUCTRAN: A program for computing final nuclide concentrations using a direct simulation approach

It is essential to precisely determine the evolving concentrations of radioactive nuclides within transmutation problems. It is also a crucial aspect of nuclear physics with widespread applications in nuclear waste management and energy production. This paper introduces CNUCTRAN, a novel computer program that employs a probabilistic approach to estimate nuclide concentrations in transmutation problems. CNUCTRAN directly simulates nuclei transformations arising from various nuclear reactions, diverging from the traditional deterministic methods that solve the Bateman equation using matrix exponential approximation. This approach effectively addresses numerical challenges associated with solving the Bateman equations, therefore, circumventing the need for matrix exponential approximations that risk producing nonphysical concentrations. Our sample calculations using CNUCTRAN shows that the concentration predictions of CNUCTRAN have a relative error of less than 0.001% compared to the state-of-the-art method, CRAM, in different test cases. This makes CNUCTRAN a valuable alternative tool for transmutation analysis. Program summaryProgram Title:CNUCTRANCPC Library link to program files:https://doi.org/10.17632/b484w2vx52.1Developer's repository link:https://github.com/rabieomar92/cnuctran/releasesLicensing provisions: MITProgramming language: C++Nature of problem:CNUCTRAN simulates the transmutation of various nuclides such as decays, fissions, and neutron induced reactions using a direct simulation approach. It has the capability of predicting the final concentration of a large system of nuclides altogether after a specified time step, tf.Solution method:CNUCTRAN works based on the novel probabilistic method such that it does not compute the final nuclide concentrations by solving Bateman equations. Instead, it statistically tracks nuclide transformations into one another in a transmutation problem. The technique encapsulates various possible nuclide transformations into a sparse transfer matrix, T, whose elements are made up of various nuclear reaction probabilities. Next, T serves as a matrix operator acting on the initial nuclide concentrations, y(0), producing the final nuclide concentrations, y.

Modified-TiO2 Nanotube Arrays as a Proficient Photo-Catalyst Nanomaterial for Energy and Environmental Applications

Recently, TiO2 nanotube arrays (TNTAs) have attracted researcher’s attention in the fields of energy production and environmental remediation applications; this is mainly due to their unique optoelectronic characteristics, corrosion resistance, chemical and mechanical stability. In this study, the ability of employing of TiO2 nanotube arrays-based catalysts in the field of photocatalytic CO2 reduction has been investigated. Possible modification strategies have been presented for improving the TNTAs performance by using different types of nanomaterials including graphitic carbon nitrides (g-C3N4), metal-organic frame work (MOF), reduced graphene oxide (RGO) and gold nanoparticles (Au NPs). The TNTAs composites were characterized using XRD and FESEM analyses and the results revealed the successful synthesis of these composites. The TNTAs and their composites exhibited good results for the photo-conversion of CO2 into CH4 gas product. This study gives new ideas for making and developing low-cost Ti metal-based nanomaterials which can be used in the future for recycling the CO2 gas emissions into useful solar fuels.

Enhancing the crystallinity of covalent organic frameworks to achieve improved photocatalytic hydrogen peroxide production under ambient conditions

Photocatalytic production of hydrogen peroxide (H2O2) presents a promising strategy for environmental remediation and energy production. However, achieving clean and efficient H2O2 production under ambient conditions without organic sacrificial agents remains challenging. Enhancing the low crystallinity of covalent organic frameworks (COFs) can promote the separation and transmission of photo-generated carriers, thereby boosting their photocatalytic performance. Herein, we introduce a novel synthetic approach by substituting traditional acetic acid catalysts with organic base catalysts to enhance the crystallinity of β-ketoenamine-linked COF, TpBD-COF. Compared to TpBD-COF-A synthesized using acetic acid catalysts, TpBD-COF-B, synthesized with organic base catalysts, exhibited advancements including increased absorption intensity in the visible spectrum, reduced photoluminescence intensity, enhanced photo-generated carrier separation performance, and a 2.1-fold increase in photocatalytic H2O2 production. Under visible light irradiation, TpBD-COF-B achieved a photocatalytic H2O2 production rate of 533 µmol h−1 g−1 using only air and water, without the need for organic sacrificial agents. Furthermore, TpBD-COF-B also exhibited good performance in long-term catalytic production experiments, tests with actual water bodies, and cyclic usage experiments. This study offers a strategy for enhancing the crystallinity of COFs to improve their photocatalytic activity, with promising applications in clean energy production and environmental remediation.

Long-lived doubly charged scalars in the left-right symmetric model: Catalyzed nuclear fusion and collider implications

We show that the doubly charged scalar from the SU(2)R-triplet Higgs field in the Left-Right Symmetric Model has its mass governed by a hidden symmetry so that its value can be much lower than the SU(2)R breaking scale. This makes it a long-lived particle while being consistent with all existing theoretical and experimental constraints. Such long-lived doubly charged scalars have the potential to trigger catalyzed fusion processes in light nuclei, which may have important applications for energy production. We show that it could also bear consequences on the excess of large ionization energy loss (dE/dx) recently observed in collider experiments.