Cost-effective Technology Research Articles

Triphenylamine-Based Y-Shaped Self-Assembled Monolayers for Efficient Tin Perovskite Solar Cells.

Triphenylamine-based Y-shaped organic sensitizers, specifically TPA-MN (1), TPA-CA (2), TPAT-MN (3), and TPAT-CA (4), are synthesized and utilized as p-type self-assembled monolayers (SAMs) for tin-based perovskite solar cells (TPSCs). These SAMs are developed using low-cost starting materials, primarily from triphenylamine (TPA) components. An extensive analysis is conducted to examine the crystalline, morphological, thermal, optical, electrochemical, and optoelectronic characteristics of SAMs 1-4, and the results are compared. A two-step method is employed to successfully develop tin perovskite layers on all four SAM surfaces. The resulting devices demonstrates PCE in the following order: TPAT-CA (8.1%) > TPAT-MN (6.1%) > TPA-MN (5.0%) > TPA-CA (4.2%). The TPAT-CA molecule, which contains a thiophene spacer, performed better than the other three SAMs in terms of rapid hole extraction rate, high hole mobility, and retarded charge recombination. Consequently, SAM TPAT-CA exhibited the highest device performance with excellent stability over time, retaining ≈90% from the beginning values after storage for 3000 h. The innovative Y-shaped SAMs describe in this study, characterized by their simple and efficient design, have the potential to contribute significantly to the advancement of perovskite photovoltaics, particularly in the development of cost-effective TPSC technology.

Sustainable bioethanol production by solid-state fermentation: a systematic review.

The escalation of the global population has accelerated the demand for sustainable energy sources such as bioethanol. Traditionally, bioethanol was obtained by the fermentation of sugar from agricultural crops and grains. However, this technique creates serious threats on the global food supplies, thus hindering the commercial production of bioethanol. Therefore, there is a need to develop new technologies and low-cost raw materials in order to ensure that bioethanol is economically comparable to the first generation of bioethanol. Solid-state fermentation (SSF) has been in the limelight within the scientific community because of its efficiency, cost-effectiveness, and promising technology to produce bioethanol. SSF involves the cultivation of microorganisms on a solid substrate in the absence of free-flowing water, which eliminates the need for sugar extraction and reduces wastewater production. This systematic review provides an overview of the applications of SSF in bioethanol production while presenting recent studies and advancements of this technology for producing sustainable and cost-effective bioethanol.

Prioritizing sustainability of renewable energy projects in Morocco

Purpose The purpose of the study is to examine the electricity generation potential of different renewable energy sources in Morocco, as well as to propose a novel decision support model to prioritize renewable energy alternatives. The aim is to provide recommendations that support Morocco’s energy transition strategy and assist policymakers in devising future sustainable energy policies. Design/methodology/approach The paper integrates the analytic hierarchy process with expert feedback to prioritize five renewable energy alternatives – solar photovoltaics (PV), concentrated solar panels (CSP), wind, hydro and biomass – specific to the Moroccan context. The model uses 14 sub-criteria clustered into four main categories: economic, technological, socio-political and environmental. The criteria were weighted based on inputs from local energy sector experts to capture the distinct priorities and contextual specificities of Morocco’s renewable energy landscape. Findings The study’s findings emphasize the dominance of economic criteria among Moroccan experts. Solar PV emerged as the most suitable option due to its cost-effectiveness and alignment with Morocco’s policies to support solar energy, followed by hydropower and wind. CSP and biomass ranked lowest due to high costs and limited viability. Research limitations/implications This study highlighted the need for quality data to support informed decision-making, as well as for a centralized database to facilitate access to consistent information on renewable energy projects. Practical implications It is recommended that policymakers prioritize mature and cost-effective technologies by establishing supportive regulatory frameworks and expanding investments in hybrid renewable energy infrastructures. Originality/value In addition to introducing the Analytic Hierarchy Process model for the first time within the Moroccan context, to the best of the authors’ knowledge, this research draws recommendations to assist Moroccan policymakers in devising future sustainable policies for the energy sector.

Planning and Optimisation of Renewable Energy Systems for Decarbonising Operations of Oil Refineries

AbstractGiven the urgency to transition to low carbon future, oil refineries need to identify feasible strategies for decarbonisation. One way to address this is by integrating renewable energy systems. However, the high initial costs and intermittency appeared to be the key barriers for the adoption of renewable energy technologies. Hence, a multi-period optimisation model is developed via mixed integer linear programming in this work to determine the optimal renewable energy system in terms of cost and its optimal energy storage technology to enhance its flexibility for oil refinery operations. This model aims to minimise the costs of the renewable energy system while considering its ability to accommodate the varying energy demands across the time periods. An oil refinery case study is used to demonstrate the effectiveness of the developed model. The developed model is expected to propose an optimal renewable energy system that meets the energy demands and, at the same time, achieves the decarbonisation goal. Based on the results, the optimal renewable energy system comprises cost-effective technologies to generate various energy outputs including electricity, hydrogen, high-pressure and medium-pressure steam to meet energy demands. Additionally, the result of the case study shows that the integration of renewable energy systems achieves a reduction of 5,353 tonnes of carbon dioxide. Apart from that, the incorporation of energy-efficient energy storage results in a 10% reduction in the total cost of the optimal renewable energy system. Compressed hydrogen gas storage and battery were used to store excess hydrogen and electricity during periods with low demands and subsequently consumed during peak demand periods. This can, therefore, reduce the technological capacity required. With the aid of storage facilities, the flexibility of the renewable energy system is elevated in meeting varied demands, which otherwise would incur additional expenses.

Phase II study on the safety and immunogenicity of single-dose intramuscular or intranasal administration of the AVX/COVID-12 “Patria” recombinant Newcastle disease virus vaccine as a heterologous booster against COVID-19 in Mexico

BackgroundThe global inequity in the distribution of COVID-19 vaccines underscores the urgent need for innovative and cost-effective vaccine technologies to address access disparities and implement local manufacturing capabilities. This is essential for achieving and sustaining widespread immunity, and for ensuring timely protection of vulnerable populations during future booster campaigns in lower- middle income countries (LMICs). MethodsTo address this need, we conducted a phase II clinical trial to evaluate the safety and immunogenicity of the locally manufactured AVX/COVID-12 “Patria” (AVX) vaccine as a booster dose. The vaccine was administered either intramuscularly (IM) or intranasally (IN) to participants who had previously completed a vaccination regimen for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using adenoviral vector, inactivated virus, or mRNA-based vaccines. Participants with initial anti-spike IgG titers below 1,200 U/mL were included, allowing us to observe the booster effect induced by vaccination. ResultsBoth IM and IN immunization with AVX were found to be safe and well-tolerated. The vaccine induced a significant (>2.5-fold) increase in neutralizing antibodies against the ancestral Wuhan strain and variants of concern (VOCs), including Alpha, Beta, Delta, and Omicron (BA.2 and BA.5). This immune response was further supported by increased cellular production of interferon-gamma (IFN-γ), demonstrating a robust and multifaceted immune reaction. ConclusionsThe administration of AVX as a booster dose, whether through IM or IN routes, was safe and well-tolerated. The vaccine extended immune responses not only against the ancestral Wuhan-1 strain but also against various VOCs. Its ability to enhance preexisting immune responses suggests a potential contribution to expanding and sustaining herd immunity within the population.

Sustainable Manufacturing Engineering: Enhancing Product Quality through Green Process Innovations

The imperative for sustainable practices within manufacturing has become increasingly critical, driven by environmental concerns, regulatory pressures, and the evolving expectations of eco-conscious consumers. This paper investigates the role of sustainable manufacturing engineering in enhancing product quality through the implementation of green process innovations. Specifically, the study explores how sustainable manufacturing methods, including energy-efficient systems, additive manufacturing, zero-waste production, and renewable energy integration, can drive quality improvements while reducing the environmental impact of production processes. The research is grounded in a comprehensive analysis of current green innovations in the manufacturing sector, drawing on case studies of companies that have successfully balanced quality and sustainability. The findings indicate that companies adopting sustainable practices not only reduce waste and lower emissions but also experience notable gains in product durability, customer satisfaction, and brand reputation. For instance, additive manufacturing is shown to improve precision and material efficiency, while zero-waste initiatives lead to a more efficient resource cycle, which in turn supports consistent quality standards. This paper further delves into the challenges of implementing green manufacturing processes without compromising product quality, examining factors such as initial costs, technological readiness, and market adaptation. Visual data in the form of tables and graphs are presented to compare different green process innovations and their respective impacts on quality and sustainability metrics. In addition, case study summaries provide real-world examples of how leading companies have enhanced product quality through sustainable engineering approaches. This study underscores the value of sustainable manufacturing engineering as a dual-benefit strategy that can drive environmental stewardship alongside quality enhancement. The paper recommends that future research focus on the development of new, cost-effective green technologies and the application of advanced data analytics for improved process control in sustainable manufacturing. Through these efforts, the manufacturing sector can continue advancing toward a more sustainable, high-quality production paradigm.

Cu-Based Praseodymium-Modified γ-Al2O3 Oxygen Carrier for Chemical Looping Combustion Process Optimization

Chemical looping combustion (CLC) emerges as a cost-effective CO2 capture technology, demonstrating high competitiveness for both industrial and energy applications. This study explores the synthesis of a Cu-based, praseodymium (Pr)-modified gamma-alumina-supported (20CuPA) oxygen carrier (OC) through the wet impregnation method and investigates its performance in CLC. The characteristics of the synthesized OC were investigated using field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, temperature-programmed reduction analysis, and X-ray diffraction analysis. The CLC of methane gas was performed in a thermogravimetric analyzer (TA-Q50). The oxygen transport capacity (OTC) of the 20CuPA-based OC was investigated for 10 redox cycles. The impact of temperature and time as process variables in determining the OTC of OCs was studied. The TGA results indicated that the most important factor influencing the optimization of the OTC of OCs was time. In comparison to time, temperature had less of an impact on the OTC of 20CuPA-OC. The maximum OTC of 20CuPA-OC, which was 0.0546 mg of O2/mg of OC, was reached using optimized process variables, including a temperature of 800 °C and a time of 3 min.

Green showcases as a model for the conceptual re-signification of smart tourist destinations applied to the Amazon

This article presents the main functionalities of an autonomous device named S.A.N.D.R.O., powered by solar energy and featuring minimalist computational technology based on the Raspberry Pi. This device was originally conceived to enable the continuity of distance education in regions devoid of connectivity, such as many riverside localities in the Amazon. It became central in equipping schools with the purpose of remotely providing educational resources in crisis situations, as occurred in the year 2020 with the COVID-19 pandemic. These resources can be accessed through smartphones or kiosks, given that they fully replicate the modus operandi of the Internet, offering users a familiar experience despite the lack of actual internet connectivity. Beyond these adverse periods, one of the possible uses for the artifact is to enhance the ecotourism experience in the region, thereby contributing to transforming it into a Smart Tourist Destination. By adopting an innovative approach that reduces costs for consumers, the device can also be classified as a form of frugal innovation. This classification stems from its minimalist design and cost-effective technology, making advanced services accessible to communities and tourists in remote areas without requiring significant financial investment.

Technical characteristics and development trend of third generation solar cells

The future of global sustainable energy systems is anticipated to heavily rely on photovoltaic solar energy (PV). This paper provides an analysis of third-generation solar cells, exploring their underlying working mechanisms, evaluating their performance metrics, and discussing both their advantages and disadvantages. Third-generation solar cells, which include perovskites, dye-sensitized cells, and organic photovoltaics, offer promising advancements over traditional silicon-based cells, such as higher efficiencies and potential for lower production costs. However, challenges like material stability, scalability, and long-term reliability hinder their widespread adoption. In offering a comprehensive examination of these advanced solar technologies, the paper aims to contribute to the understanding and progress of renewable energy solutions. It underscores the importance of continued research and innovation in overcoming the existing limitations of third-generation solar cells. The transition towards a future that relies more heavily on sustainable energy sources hinges on the ability to develop and implement efficient, reliable, and cost-effective solar technologies. The paper identifies these bottleneck issues and suggests pathways for overcoming them.

Simultaneous nitrification and denitrification framework for decentralized systems: Long-term study utilizing rope-type biofilm media under field conditions

This research introduces a novel approach to achieve simultaneous nitrification-denitrification (SND) under dynamic load conditions using a cost-effective rope-type biofilm technology. The approach represents a significant advancement in wastewater treatment, particularly beneficial for remote and decentralized communities. The biofilm-based SND process was developed using a pilot-scale flow-through reactor by implementing upstream carbon management with constant-timer-based aeration control versus dynamic-sensor-based aeration control strategies. The findings indicate that adding an upstream anaerobic pretreatment process to handle excess carbon plays a substantial role in achieving a sustainable SND process under a dynamic load environment using simple aeration on-off control. The most optimal nitrification performance of 0.32 g NH3-N/m2/d (89 % removal) was achieved under a 1-hour ON/30-minute OFF aeration. The process sustained an average bulk liquid DO of 5.16 mg/L and 3.80 mg/L during the aeration ON and OFF periods, respectively, facilitating a 0.13 g N/m2/d (41 %) total inorganic nitrogen (TIN) removal, notably, implementing advanced aeration strategies driven by DO, NH3, and NO3 sensors enhanced TIN removal efficiency to 72 %. The nitrification performance remained comparable (89 % removal), resulting in 3 and 10 mg N/L effluent ammonia and TIN concentration, respectively. Additionally, utilizing two multivariate approaches accounting for 82 % and 64 % of the variance, this study discerned patterns in monitored variables and performance. Additionally, the analysis underscored the difference of bulk liquid DO levels in the biofilm versus suspended systems inhibiting the SND process. Distinct bacterial communities were established in biofilms under aerobic, anaerobic, and SND conditions, with the SND reactor showing a hierarchy of functional group and enzymes, enriched sequentially from heterotrophs to denitrifiers, nitrifiers, and anammox bacteria. These innovations underline the potential of tailored control strategies to enhance a passive biofilm-based SND process efficiency under dynamic conditions, providing scalable solutions for diverse target water quality demands in remote communities and decentralized systems.

Impact of Substrate upon Morphology, Luminescence, and Wettability of ZnMgO Layers Deposited by Spray Pyrolysis

In this work, we report on a comparative study of the topology, luminescence, and wettability properties of ZnMgO films prepared by a cost-effective spray pyrolysis technology on GaAs substrates with (100), (001), and (111) crystallographic orientations, as well as on Si(100) substrates. Deposition on nanostructured GaAs substrates was also considered. It was found that film growth is not epitaxial or conformal, but rather, it is granular, depending on the nucleating sites for the crystallite growth. The distribution of nucleation sites ensured the preparation of nanostructured films with good uniformity of their topology. The observed difference in columnar growth on Si substrates and pyramidal growth on GaAs ones was explained in terms of the impact of chemical bonding in substrates. The films grown on GaAs substrates with a (001) orientation were found to be made of larger crystallites compared to those deposited on substrates with a (111) orientation. These effects resulted in a difference in roughness of a factor of 1.5, which correlates with the wetting properties of films, with the most hydrophobic surface being found on films deposited on GaAs substrates with a (111) orientation. The prospects for photocatalytic and gas sensor applications of films produced on flat substrates, as well as for plasmonic and other applications of films deposited on nanostructured substrates, are discussed, taking into account the results of the analysis of their photoluminescence properties.

CuO/Cu(OH)2@g-C3N4 derived from CuBTC/g-C3N4 for two channel photocatalytic hydrogen peroxide production

Photocatalytic production of H2O2 is indeed a safe, sustainable and cost-effective technology, offering an environmentally friendly solution to the energy crisis through solar photocatalysis. However, it still faces challenges such as reliance on organic electron donors and pure O2, as well as inefficiencies in hole utilization. To overcome these limitations, a dual-channel photocatalytic system has been developed. In this study, we showcase the efficiency of the CuO/Cu(OH)2@g-C3N4 composite, derived from CuBTC/g-C3N4 via NaOH treatment, as a high-performance dual-channel photocatalyst for H2O2 production. Under visible light (λ ≥ 420 nm), this composite achieves a H2O2 yield of 1354 μmol/L in 120 min without any sacrificial agent, outperforming g-C3N4 by 8.4 times, CuO by 13.6 times and CuO@g-C3N4 by 1.9 times. Quenching experiments and electron paramagnetic resonance spectra confirmed that HO• and O2•− are intermediate products in the photocatalytic process, following a two-step single-electron reaction pathway. The superior activity of CuO/Cu(OH)2@g-C3N4 in H2O2 generation can be attributed to the synergistic effects of OH bonds on the CuO@g-C3N4 Z-type heterojunction and Cu(OH)2. This research presents a straightforward and promising approach for developing highly efficient photocatalysts for energy conversion.

Sustainable Solutions for Co-Gasification of Sewage Sludge and Biomass: Insights from Aspen Plus, Response Surface Methodology, and Multi-Criteria Decision-Making Integration

This paper presents a novel framework integrating process simulation, optimization, and multi-criteria decision-making (MCDM) to identify sustainable co-gasification solutions for sewage sludge (SS) and biomass. Gasifier modeling in Aspen Plus, validated with experimental data, evaluated five feedstock blend routes. Sensitivity analysis was conducted on key gasification parameters, while Response Surface Methodology (RSM) optimized process routes by revealing complex relationships between variables and performance metrics. MCDM was applied to assess alternatives based on eight criteria covering environmental, economic, and social sustainability. The study introduced an integrated objective weighting method, leveraging data variations and correlations, alongside a vector-based ranking approach for prioritizing solutions. Results indicated that a biomass-to-sewage sludge ratio of 3:7, under co-gasification conditions of 649.72°C, 1.13atm, and a steam to feedstock ratio of 0.5, achieved the highest sustainability score of 0.506. This configuration outperformed other alternatives in terms of sustainability. Validation through three distinct analytic methods confirmed the robustness of the MCDM framework. In general, this work integrates simulation, RSM optimization, and MCDM analysis into a streamlined tool, offering a systematic progression from process simulation to decision-making. It reduces the reliance on costly trial-and-error experimentation while ensuring optimal operating conditions and comprehensive sustainability evaluation. These contributions tackle key challenges in data handling, optimization, and assessment, enabling more sustainable and cost-effective environmental technology innovations.

Hydrothermal synthesis of CeSe anchored on graphitic carbon nitride nanoclusters as an electrocatalyst for enhanced oxygen evolution reaction

The oxygen evolution reaction (OER) is a critical half-reaction in the process of water splitting, yet its practical application is hindered by slow kinetics and the high cost of conventional electrocatalysts. This study explores the potential of a novel CeSe/g-C3N4 nanocomposite as an efficient catalyst for OER in an alkaline environment. The CeSe/g-C3N4 nanocomposite exhibits exceptional electrocatalytic performance, demonstrated by a low overpotential of 196 mV at a current density of 10 mA cm−2 and a reduced onset potential of 1.29 V versus the reversible hydrogen electrode (RHE). Additionally, nanocomposite's Tafel slope of 58.14 mV/dec is significantly lower compared to pure CeSe (76.89 mV/dec) and multi-layered g-C3N4 (89.76 mV/dec), indicating superior kinetic behavior. Remarkably, the CeSe/g-C3N4 composite also demonstrates excellent electrochemical stability, maintaining its performance over a 40-hour period. These findings suggest that the CeSe/g-C3N4 nanocomposite not only enhances the electrocatalytic properties necessary for OER but also holds the potential to outperform traditional noble metal-based catalysts, paving the way for more cost-effective and efficient water-splitting technologies.

A multi-dimensional comparative study on the performance of algae removal using various flotation

Flotation is considered the most cost-effective and efficient algae-water separation technology. However, there are various flotation techniques for algae removal, such as coagulation-flotation (CF), foam flotation (FF), and positively charged bubble flotation (PF). It remains unclear which method is most suitable for removing algae from water bodies and under what specific conditions each technique is most effective. This study systematically compares CF, FF, and PF in terms of algal cell removal efficiency, concentration ratio, flotation kinetics, impact on algal cells, removal efficiency of algal organic matter (AOM) and microcystins (MC-LR), as well as economic cost analysis. CF is better suited for algae removal in water bodies, including drinking water sources, using fixed installations on shore due to its high removal efficiency, high concentration ratio, low chemical dosage, and minimal residuals. FF is more appropriate for non-drinking water sources as it can remove algae and further control algal growth; however, its residual CTAB may pose a threat to drinking water safety. PF is most suitable for in situ algae removal within water bodies, primarily because it does not require stirring or coagulation. Instead, modified bubbles can be directly introduced into the algal distribution layer, where they adhere to algal cells, facilitating algae-water separation. All three flotation methods are economically feasible for algae removal. For FF, the costs of chemicals and electricity are nearly equal, while for CF and PF, the primary cost is electricity. This study provides data to support the selection of appropriate flotation technologies for emergency removal of algal blooms in water bodies.

Insights into the chili phytochemicals, bioactive components, and antioxidant activity of instant premixes (green and red chilies) and their reconstitution products

Chili fruits are a potential source of phytochemicals and nutrients for food and reconstituted products. Due to its high nutritional and bioactive components, the current study focused on developing chili instant food products employing hot-air drying method. The effect of the hot-air drying method on physicochemical properties, microbiological quality, retention of bioactive components, phytochemicals, antioxidant properties, and sensory quality of green and red chilies reconstitution products were investigated. HPLC quantification unveiled that fresh red chili product had retained the highest capsaicin (2703.14 µg/g) and dihydrocapsaicin (1518 µg/g) content on the 0th day. Furthermore, UPLC-MS confirmed the presence of eleven phenolic compounds such as gallic acid, chlorogenic acid, caffeic acid, syringic acid, p-coumaric acid, protocatechuic acid, trans-cinnamic acid, ferulic acid, catechin, rutin, and quercetin. Among all, ferulic acid (382.91 µg/g) was the most abundant phenolic compound in fresh green chili products, followed by trans-cinnamic acid (73.19 µg/g) in green chili reconstituted and catechin (65.66 µg/g) in green and red chili reconstituted products. The chili products retained reasonable amounts of bioactive components and antioxidants during storage without microbial growth. The correlation analysis revealed a significant correlation between capsaicinoids, phenolic compounds, and antioxidant properties, which are linearly related in green chili products. This study offers manufacturers a cost-effective technology for producing high-quality chili-reconstituted products rich in essential nutrients and health benefits.Graphical

Use of Sustainable Energy Systems in Educational Institutions

Educational institutions like other public and private organizations should try to eliminate their carbon footprint for the achievement of the ambitious 2050 target of net-zero carbon emissions. Several mature, reliable and cost-effective sustainable energy technologies can be used in these institutions replacing the use of fossil fuels and reducing their carbon emissions. Solar energy, wind energy and biomass can be used for heat and electricity generation replacing the use of oil, gas and grid electricity. Additionally, various low-carbon emission technologies including heat pumps, co-generation systems, fuel cells, district heating systems and power storage technologies can be also used in them. The combined use of these technologies in schools, colleges and universities can replace the current use of conventional energy sources reducing or completely eliminating their carbon emissions. The abovementioned benign energy technologies are already used commercially in several sectors proving their reliability and cost-effectiveness. It has been indicated that a plethora of green energy technologies can be used in educational institutions eliminating their carbon footprint achieving the desired global 2050 target of net-zero carbon emissions. Our results could be useful to policy makers and to the authorities of schools, colleges and universities who are willing to promote their environmental sustainability, achieving economic benefits and offering valuable educational opportunities to students.

Flexible and highly selective NO2 gas sensor based on direct-ink-writing of eco-friendly graphene oxide for smart wearable application

Nitrogen dioxide (NO2) is a major cause of respiratory disorders in outdoor and indoor environments. Real-time NO2 monitoring using nonintrusive wearable devices can save lives and provide valuable health data. This study reports a room-temperature, wearable, and flexible smart NO2 gas sensor fabricated via cost-effective printing technology on a polyimide substrate. The sensor uses alkali lignin with edge-oxidised graphene oxide (EGO-AL) ink, demonstrating a sensitivity of 1.70% ppm⁻1 and a detection limit of 12.70 ppb, with excellent selectivity towards NO2. The high sensing properties are attributed to labile oxygen functional groups from GO and alkali lignin, offering abundant interacting sites for NO2 adsorption and electron transfer. The sensor fully recovers to the baseline after heat treatment at 150 °C, indicating its reusability. Integration into lab coats showcased its wearable application, utilising a flexible printed circuit board to wirelessly alert the wearer via cell phone to harmful NO2 levels (>3 ppm) in the environment. This smart sensing application underscores the potential for practical, real-time air quality monitoring, personal safety enhancement, and health management.

Applications of nickel-containing structured microfibrous catalysts for the process of propane hydrogenolysis

This work evaluates the possibility of using nickel-containing structured glass fiber catalysts (Ni/GFC) for the process of hydrogenolysis of gas condensate (GC) into transportable components of natural gas, which will increase the efficiency of GC processing and contribute to the development of more cost-effective technologies in the oil-gas industry. Ni/GFC samples with Ni content of 5, 10 and 15% wt. were synthesized by surface thermal synthesis (STS). An industrial granular catalyst with a mass Ni content of 16% was used to compare the catalytic activity of the obtained catalysts. The highest activity and selectivity of methane formation is observed on the 10% Ni/ GFC catalyst, by these parameters it is superior not only to other GFCs, but also the traditional granular catalyst.

N-type and P-type series integrated hydrogel thermoelectric cells for low-grade heat harvesting

Low-grade heat is abundant and ubiquitous, but it is generally discarded due to the lack of cost-effective recovery technologies. Ion thermoelectric cells are an affordable and straightforward approach of converting low-grade heat into usable electricity for sustainable power. Despite their potential, ion thermoelectric cells face challenges such as limited Seebeck coefficient and required series integration. Here, we demonstrate that the N-type and P-type conversion of ion thermoelectric cells can be achieved through the phase transition of temperature-sensitive hydrogel containing the triiodide/iodide redox couple. Through the strong interaction between the hydrophobic region of the hydrogel and triiodide, the hydrophobic side selectively captures triiodide and the hydrophilic side repels triiodide, raising the concentration difference of triiodide and thereby increasing the Seebeck coefficient. Specifically, the Seebeck coefficient of the N-type ion thermoelectric cells is 7.7 mV K−1, and the Seebeck coefficient of P-type ion thermoelectric cells is −6.3 mV K−1 (ΔT = 15 K). By connecting 10 pairs of the N-type and P-type ion thermoelectric cells, we achieve a voltage of 1.8 V and an output power of 85 μW, surpassing the reported triiodide/iodide-based ion thermoelectric cells. Our work proposes a phase transition strategy for the N-P conversion of ion thermoelectric cells, and highlights the prospect of series integrated hydrogel ion thermoelectric cells for low-grade heat harvesting.