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Perovskite solar cells with an indium tin oxide (ITO)/SnO2/CH3NH3PbI3/Spiro-OMeTAD/2,2,2-trifluoroethanol (TFE) doped single-walled carbon nanotube (SWCNT) structure were developed by dropping TFE onto SWCNTs, which replaced the metal back electrode, and a conversion efficiency of 14.1% was achieved. Traditionally, acidic doping of the back electrode, SWCNT, has been challenging due to the potential damage it may cause to the perovskite layer. However, TFE has facilitated easy doping of SWCNT as the back electrode. The sheet resistance of the SWCNTs decreased and their ionization potential shifted to deeper levels, resulting in improved hole transport properties with a lower barrier to carrier transport. Furthermore, the Seebeck coefficient (S) increased from 34.5 μV/K to 73.1 μV/K when TFE was dropped instead of EtOH, indicating an enhancement in the behavior of p-type charge carriers. It was observed that hydrophilic substances adhered less to the SWCNT surface, and the formation of PbI2 was suppressed. These effects resulted in higher conversion efficiency and improved solar cell performance. Furthermore, the decrease in conversion efficiency after 260 days was suppressed, showing improved durability. The study suggests that combining SWCNTs and TFEs improves solar cell performance and stability.

The durability of super-low friction of hydrogenated carbon nitride (CNx:H) coatings sliding against Si3N4 balls in high-vacuum (HV) environments and the phenomena that occur at the interface were clarified. In an HV, CNx:H achieved super-low friction (µ

Ammonia protonic ceramic fuel cells (NH3-PCFCs) are highly appealing energy conversion technologies due to their high efficiency, environmental responsibility, and benign safety features. Nonetheless, progress in NH3-PCFCs is notably impeded by the restricted performance and insufficient lifespan of standard Ni-cermet anodes for ammonia cracking, especially at 550 °C or below. Herein, we report an efficient ammonia cracking layer with a formula of xCo3O4/100-xBaZr0.8Y0.2O3-δ (Co/BZY) (x=10, 20, 30), which is deposited onto the Ni-BaZr0.1Ce0.7Y0.1Yb0.1O3−δ (BZCYYb) anode to significantly enhance the NH3 decomposition catalytic activity, thereby improving the performance and durability of NH3-PCFCs at low temperatures. The cells with the addition of a 20Co/80BZY anode catalytic layer (ACL) exhibit low area-specific resistance (ASR) and promising operational longevity under NH3 conditions. At 550°C, the NH3-PCFCs with a 20Co/80BZY ACL exhibit a high peak power density of 0.626 W cm−2 and promising operation durability. This study provides important guidance for constructing high-performance and durable NH3-PCFCs.

High-density polyethylene (HDPE) geomembranes are commonly used as an environmental protection liner due to their good chemical and mechanical resistances and low cost. Ultraviolet (UV) radiation is an essential issue in durability studies for pond applications. This study evaluated a 1.5-mm thick HDPE geomembrane exposed to ultraviolet fluorescent radiation for 8760 h in a laboratory and thermoanalytical and physical analyses were conducted towards the understanding of its performance after exposure. According to the results, although the geomembrane maintained the ductile behavior, it showed a 52.48% final decrease in stress crack resistance (SCR) compared to virgin SCR. Moreover, a considerable antioxidant depletion occurred after 8760 h exposure shown by the Std. OIT (standard oxidative-induction time) results, demonstrating a Std. OIT value decrease of 89.19% compared to the virgin Std. OIT. Such a behavior contributed to the susceptibility of thermal effects in the DSC (differential scanning calorimetry) curves and the losses observed in the SCR values, attesting the geomembrane’s oxidative degradation mechanism occurred and changed the polymer’s structure.

Two methods of durability prediction of fillet welds were researched in this study. Namely, the structural Hot-Spot method and the structural stress method fe-safe Verity were applied to fatigue life estimation of a double plate lap fillet weld made of high-strength complex phase CP-W800 steel. Durability predictions were compared against available high-cycle fatigue experimental data obtained for the same weld detail and material. Both 2D and 3D finite element meshes were considered in the simulations. It was shown that comparable predictions were obtained using either the Hot-Spot method or the fe-safe Verity module in the case of the 3D FE mesh. On the contrary, a less conservative durability prediction was observed using the Hot-Spot method and a more conservative durability prediction was gained using the fe-safe Verity module in the case of the 2D FE mesh due to a different consideration of stress concentration around the weld.

To ensure the operational safety of the automatic couplers of a rolling stock subjected to cyclic loading, reliability and residual service life must be determined. This paper involved the prediction of the durability of the automatic coupler SA3 by analytical summation of cyclic damage. During the investigation, the cyclic characteristics and damage modes of the automatic coupler material that influence the accumulation of damage are determined. The stress and strain state assessment model was developed using a 3D finite element method for the automatic coupler housing as a geometrically complex component. A methodology was used to assess damage per load cycle that is applicable to any sequence of automatic coupler load cycles. For this purpose, the authors used low-cycle stationary load dependencies that account for quasi-static and low-cycle fatigue damage. The investigation showed that a coupler may develop a crack due to accumulated quasi-static and fatigue damage. For damage summation, the dependences of low-cycle stationary stress-controlled load accounting for low-cycle, quasi-static fatigue damage are proposed in view of the variation of the load on the automatic coupler during operation depending on the weight of the rolling stock, velocity, and railway relief. The proposed methodology is applicable to the calculation of other housings under similar loading conditions.

The real implementation of biogas reforming at an industrial scale to obtain interesting products (like hydrogen or syngas) is a developing research field where multidisciplinary teams are continuously adding improvements and innovative technologies. These works can contribute to the proliferation of green technologies where the circular economy and sustainability are key points. To assess the sustainability of these processes, there are different tools like life cycle assessment (LCA), which involves a complete procedure where even small details count to consider a certain technology sustainable or not. The aim of this work was to review works where LCA is applied to different aspects of biogas reforming, focusing on the role of catalysts, which are essential to improve the efficiency of a certain process but can also contribute to its environmental impact. In conclusion, catalysts have an influence on LCA through the improvement of catalytic performance and the impact of their production, whereas other aspects related to biogas or methane reforming could equally affect their catalytic durability or reusability, with a subsequent effect on LCA. Further research about this subject is required, as this is a continuously changing technology with plenty of possibilities, in order to homogenize this research field.

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The pursuit of durable and sustainable construction has driven interest in innovative materials, with superabsorbent polymers (SAPs) emerging as a promising solution, especially for the concrete industry. SAPs offer significant benefits to the durability of concrete structures, including mitigation of autogenous shrinkage, enhanced freeze–thaw resistance, crack sealing, and stimulation of autogenous healing. This study focuses on the impact of internal curing with SAPs on crack formation and corrosion initiation in large-scale reinforced concrete walls (14 m × 2.75 m × 0.8 m). Both commercial SAPs based on acrylic acid chemistry and in-house-developed SAPs based on alginates were evaluated. Key findings reveal that the reference wall exhibited visible cracking just five days after casting, while the SAP-treated wall remained crack-free throughout a 24-month monitoring period. Moreover, the reference wall showed corrosion initiation at two locations near the cracks within six months, whereas the SAP-treated wall exhibited no signs of corrosion potential. Laboratory tests further demonstrated a slight reduction in chloride penetration and carbonation in SAP-treated specimens compared to the reference. These results highlight the efficacy of SAPs in enhancing the durability and longevity of reinforced concrete structures.

To reveal the influence of joint type and epoxy-coated steel bar surface damage on the durability of assembled bridge piers, this study simulated the potential damage to epoxy-coated steel bars at various stages of an actual construction process by bending, scratching, and knocking. The pier inter-segmental joint and the pier-bearing platform joint were designed to highlight the critical zones affecting the durability of sea-crossing bridge substructures. The migration of chloride ions into the concrete was accelerated by applying a constant voltage DC electric field. The electrochemical indexes of epoxy-coated steel bars and chloride ion content in concrete were measured regularly. Results show that the corrosion risk and corrosion rate of steel bars increase significantly when the damaged area ratio of epoxy coating is higher than 5%. The chloride ion transport rate at the interface of the pier-bearing platform joint is about 5 times that of the pier inter-segmental joint. The service life of the pier-bearing platform joint is only 1/2 that of the pier inter-segmental joint when epoxy-coated steel bars with the same treatment are used.

Nanoclay, a processed clay, is utilized in numerous high-performance cement nanocomposites. This clay consists of minerals such as kaolinite, illite, chlorite, and smectite, which are the primary components of raw clay materials formed in the presence of water. In addition to silica, alumina, and water, it also contains various concentrations of inorganic ions like Mg2+, Na+, and Ca2+. These are categorized as hydrous phyllosilicates and can be located either in interlayer spaces or on the planetary surface. Clay minerals are distinguished by their two-dimensional sheets and tetrahedral (SiO4) and octahedral (Al2O3) crystal structures. Different clay minerals are classified based on the presence of tetrahedral and octahedral layers in their structure. These include kaolinite, which has a 1:1 ratio of tetrahedral to octahedral layers, the smectite group of clay minerals and chlorite with a 2:1 ratio. Clay minerals are unique due to their small size, distinct crystal structure, and properties such as high cation exchange capacity, adsorption capacity, specific surface area, and swelling behavior. These characteristics are discussed in this review. The use of nanoclays as nanocarriers for fertilizers boasts a diverse array of materials available in both anionic and cationic variations. Layered double hydroxides (LDH) possess a distinctive capacity for exchanging anions, making them suitable for facilitating the transport of borate, phosphate, and nitrate ions. Liquid nanoclays are used extensively in agriculture, specifically as fertilizers, insecticides, herbicides, and nutrients. These novel nanomaterials have numerous benefits, including improved nutrient use, controlled nutrient release, targeted nutrient delivery, and increased agricultural productivity. Arid regions face distinct challenges like limited water availability, poor soil quality, and reduced productivity. The addition of liquid nanoclay to sandy soil offers a range of benefits that contribute to improved soil quality and environmental sustainability. Liquid nanoclay is being proposed for water management in arid regions, which will necessitate a detailed examination of soil, water availability, and hydrological conditions. Small-scale trial initiatives, engagement with local governments, and regular monitoring are required to fully comprehend its benefits and drawbacks. These developments would increase the practicality and effectiveness of using liquid nanoclay in desert agriculture.

The durability of reinforced concrete structures is a significant concern, with corrosion of reinforcement being a leading cause of reduced durability. To ensure accurate models, it is necessary to calibrate or validate them with direct measurements of the structures, specifically monitoring durability-related parameters. The heterogeneity of structures and the dispersion of the parameters considered in models make this calibration or validation essential. To enable the predictive maintenance of structures, it is essential to monitor the parameters related to their durability. This article presents the results of the monitoring of the temperature, corrosion potential, resistivity, and corrosion rate of two structural components, a beam and a tendon, for over 10 months. The obtained values were correlated with the climate to which they were exposed. The corrosion rate can be correlated with the influence of climate, enabling real-time estimation of section loss. This is a necessary step towards the digitization of structures or the development of digital twins that incorporate the effect of corrosion.

This paper investigates the mechanical properties and the durability implications of innovative cement-based mortars doped with carbon microfibers. In particular, mixes with different amounts of carbon additions are produced, and the properties of fresh and hardened samples are analyzed through workability, water absorption, and compressive and flexural tests under specific environmental conditions. These composites can be employed to enhance construction performance or provide structures with strain-monitoring capabilities. However, the analysis of their mechanical properties and their durability behavior is needed before extensive structural use. In this work, the preparation procedure is defined for the various mix designs, considering different amounts of carbon microfibers; then, fresh properties are evaluated, and different types of samples formed. After various curing times, the specific rheological and hardened properties of the specimens are tested in different conditions to consider the durability of the composites, essential for the real-scale adoption in structural elements. Preliminary electrical and sensing tests are first conducted to evaluate the monitoring potential of the investigated composites. The findings highlight the impact of carbon inclusions on the performance of cement-based mortars, offering valuable insights for their utilization in masonry construction or for repairing concrete structures. In particular, sensing capabilities are found to be highly enhanced by the presence of CMF. Additionally, the results of this research pinpoint key areas for further analysis in the material’s development process.

The study explores the hypothesis that crystalline hydrophilic additives (CA) can enhance concrete’s resistance to freeze/thaw cycles, crucial for assessing building durability. Employing EU standards, the research evaluates concrete resistance through standardized European freeze/thaw procedures. Monitoring concrete slabs exposed to freezing in the presence of deionized water and in the presence of 3% sodium chloride solution, the study measures surface damage and relative dynamic modulus of elasticity. Additionally, it assesses internal damage through monitoring of relative dynamic modulus of elasticity on cubes and prisms submerged in water and exposed to freezing/thawing. The pore spacing factor measured here aids in predicting concrete behavior in freeze/thaw conditions. Results suggest that the standard air-entraining agent offers effective protection against surface and internal damage due to freeze/thaw cycles. However, the CA displays potential in enhancing resistance to freeze/thaw cycles, primarily in reducing internal damage at a 1% cement weight dosage. Notably, a 3% replacement of cement with CA adversely affects concrete resistance, leading to increased surface and internal damage. The findings contribute to understanding materials that can bolster concrete durability against freeze–thaw cycles, crucial for ensuring the longevity of buildings and infrastructure.

In order to enhance the durability of fuel cell systems in fuel cell hybrid electric vehicles (FCHEVs), researchers have been dedicated to studying the degradation monitoring models of fuel cells under driving conditions. To predict the actual degradation factors and lifespan of fuel cell systems, a semi-empirical and semi-physical degradation model suitable for automotive was proposed and developed. This degradation model is based on reference degradation rates obtained from experiments under known conditions, which are then adjusted using coefficients based on the electrochemical model. By integrating the degradation model into the vehicle simulation model of FCHEVs, the impact of different fuel cell sizes and dynamic limitations on the efficiency and durability of FCHEVs was analyzed. The results indicate that increasing the fuel cell stack power improves durability while reducing hydrogen consumption, but this effect plateaus after a certain point. Increasing the dynamic limitations of the fuel cell leads to higher hydrogen consumption but also improves durability. When considering only the rated power of the fuel cell, a comparison between 160 kW and 100 kW resulted in a 6% reduction in hydrogen consumption and a 10% increase in durability. However, when considering dynamic limitation factors, comparing the maximum and minimum limitations of a 160 kW fuel cell, hydrogen consumption increased by 10%, while durability increased by 83%.

The urgent demand for terawatt-scale clean energy necessitates the rational design of noble metal catalysts with minimal noble metal loading while maintaining high catalytic activity. However, the durability of low-loading catalysts is a critical concern for their successful industrial implementation. Here, we present a capping strategy using an amorphous HfO2 (m-HfO2) to address this issue. Take Pt/C catalysts with Pt loading as low as 81.39 ng cm−2 as an example, we demonstrate that the m-HfO2 layer (10 nm) serves as an efficient mass transport channel for underneath Pt active sites, and effectively mitigates bubble-induced blockage of active sites by separating bubble formation sites with Pt active sites. Thus, the resulting catalyst exhibits a remarkable mass activity of 122.87 A mg−1 and an overpotential of 11 mV at 10 mA cm−2. Furthermore, the m-HfO2 plays a crucial role in eliminating the structural transformation and extending the lifetime of Pt-based catalysts, as evidenced by no loss of specific activity after consecutively cycling the catalyst for over 100 h. Such a capping strategy is potentially applied to other types of reactions and catalyst systems.

Following the 2011 accident at the Fukushima Daiichi Nuclear Power Plant (1F), contaminated water was treated to remove radionuclides. The water treatment processes generated ∼4500 m3 of secondary wastes including sludges and spent media. Vitrification using GeoMelt® In-Container Vitrification (ICV)™ is a technology being considered for treatment of these wastes. ICV is well suited due to its ability to process a broad range of wastes at high temperatures without the need to pour glass which results in high waste loading and high chemical durability. The objective of this study was to formulate glasses suitable for ICV processing of 1F secondary wastes with high chemical durability. Thirty-six glasses were formulated for different 1F secondary waste blends with loadings ranging from 60 to 92 wt%. Materials Characterization Center durability test number 1 (MCC-1 – ASTM C1220) responses were measured for the glasses in deionized water at 90 °C for 7 to 365 days. Their MCC-1 responses were equal or below those for well-characterized reference waste glasses from US, Japan, and France demonstrating their high durability. The 1F glass MCC-1 data were combined with literature data from US, French, and Japanese high-level waste glasses and a model was fitted to MCC-1 durability response as a function of glass composition. Component effects on MCC-1 responses were discussed in context of glass alteration theory.

The extensive usage of concrete and ordinary Portland cement has generated 5~8% of annual global CO2 emissions, causing serious environmental problems. To reduce such environmental impact, researchers have made significant efforts to develop alternative materials that may partially or entirely replace the ordinary Portland cement, such as limestone calcined clay cement (LC3). LC3 has not been commonly adopted in reality because of uncertain setting times during the transportation and construction processes. Comprehensive investigation and understanding of the setting times of LC3 has great significance to industrial upgrading. As a result, this study is committed to comprehensively reviewing the hydration process and the setting time of LC3 materials.

The performance of alkaline water electrolysis (AWE) at high current densities is limited by gas bubble generation on the surface of electrodes, which covers active sites and blocks mass transfer, resulting in lower AWE efficiency. Here, we utilize electro-etching to construct Ni electrodes with hydrophilic and aerophobic surfaces to improve the efficiency of AWE. Ni atoms on the Ni surface can be exfoliated orderly along the crystal planes by electro-etching, forming micro-nano-scale rough surfaces with multiple crystal planes exposed. The 3D-ordered surface structures increase the exposure of active sites and promote the removal of bubbles on the surface of the electrode during the AWE process. In addition, experimental results from high-speed camera reveal that rapidly released bubbles can improve the local circulation of electrolyte. Lastly, the accelerated durability test based on practical working condition demonstrates that the 3D-ordered surface structures are robust and durable during the AWE process.

This paper investigates the properties and durability of cementitious composites incorporating solid-solid phase change materials (SS-PCM), an innovative heat storage material. Mortars with varying SS-PCM contents (0%, 5%, 10%, 15%) were formulated and characterized for rheological, structural, mechanical, and thermal properties. Durability assessment focused on volume stability (shrinkage), chemical stability (carbonation), and mechanical stability (over thermal cycles). Mortars with SS-PCM exhibited significant porosity and decreased mechanical strength with higher SS-PCM content. However, thermal insulation capacity increased proportionally. Notably, the material’s shrinkage resistance rose with SS-PCM content, mitigating cracking issues. Despite faster carbonation kinetics in SS-PCM mortars, attributed to high porosity, carbonation appeared to enhance long-term mechanical performance by increasing compressive strength. Additionally, SS-PCM composites demonstrated superior stability over thermal cycles compared to reference mortars.

This study investigates the life expectancy (LE) and life cycle costs (LCC) of three alternatives of interior partitions in residential units: gypsum board, autoclaved concrete block, and hollow concrete block partitions. The aim is to examine the sustainability and cost-effectiveness of these partitions in various service and occupancy conditions. Three different service conditions were analyzed: Standard (constructed without faults), Inherent Defect Conditions (with initial, non-progressing defects), and Failure Conditions (developing defects over time). To analyze the impact of occupancy conditions, six ‘negative occupancy factors’ were identified that accelerate partition deterioration, including non-ownership, poor maintenance, high residential density, the presence of young children, the presence of domestic animals, and the density of furniture. These factors define four occupancy condition categories: light, moderate, standard, and intensive. The research found that hollow concrete block partitions are the most durable, exceeding 100 years in light or moderate conditions. Gypsum board partitions, while cost-effective, have a lower life expectancy, needing replacement in 11–27 years in intensive conditions. Autoclaved concrete blocks offer moderate durability, with similar costs to hollow blocks in normal conditions. Overall, the study highlights the influence of service and occupancy on the lifespan of interior building components, and provides recommendations for partition type selection that are based on specific conditions. These recommendations are a pivotal outcome, highlighting the study’s significant contribution to the understanding of the long-term performance and sustainability of building materials in residential construction.

Conventional driven piles are made from steel, concrete, timber, or composite materials. These piling options have limitations with respect to corrosion, durability, driveablity, and performance. Ultra-High-Performance Concrete (UHPC) pile is a new alternative that has already been adopted by various state Departments of Transportation in the United States for addressing the limitations that exist with conventional piles. UHPC piles are made of a cementitious composite material mixture that possesses exceptional properties such as higher strength, low capillary porosity, and high resistance to corrosion, making them a suitable option for use as a deep foundation. For several reasons, it is necessary to cast piles with a shorter length and splice them at the site to reach the desired lengths. These reasons include shipping limitations, unpredictable soil condition, reducing transportation costs, construction time, and damage during installation. This study aims to explore and summarize the currently available options for connecting UHPC pile segments. Accordingly, after a brief introduction on driven piles, this paper investigates various splicing systems that can be used for UHPC piles through reviewing previous research studies and field applications. The applicable splices are then compared based on several criteria such as capacity, durability, cost, and ease of application.

An oxygen reduction reaction (ORR) is the key half reaction of proton exchange membrane fuel cells (PEMFCs), and is highly dependent on Pt-based nanocrystals as core electrocatalysts. Despite the exceptional ORR activity from adjusting the electronic structures of surface or near-surface atoms, several serious issues, including the corrosion of carbon supports, the preferential leaching of active metal elements, the instability of surface low-coordinated atoms and the sintering/agglomeration of nanocrystals, still exist, challenging the ORR durability of developed Pt-based ORR catalysts. From the point of view of the catalyst structure design, in this review, we summarized the state-of-the-art structural regulation strategies for improving the ORR durability of Pt-based catalysts. The current limitation of Pt-based binary catalysts for ORR electrocatalysis is firstly discussed, and the detailed strategies are further classified into the optimization of supports, metal-doped alloys, core/shell structures, intermetallics and high-entropy alloys, etc. The structure–performance relationship is detailedly explained, especially emphasizing the elimination of the above restrictions. Finally, the existing challenges and future research direction are further presented, aiming at practicing the PEMFC devices of the ultradurable Pt-based catalysts.

Hydrophobic coatings are widely employed in liquid-vapour phase change applications, offering advantageous control on condensation dynamics. However, they suffer from poor stability under harsh conditions and their durability is often neglected over thermal performance. Here, the global performance of a hybrid octyl-modified silica coating on aluminium was studied during saturated vapour condensation, in terms of thermal efficiency and durability. The coating successfully promoted dropwise condensation with heat transfer coefficients of ∼90 kW m−2 K−1, an average 9-fold increase with respect to filmwise condensation under similar heat flux conditions. Straightforward and reproducible tests were employed to separately evaluate the different factors influencing the coating's degradation, attempting to reproduce the conditions present in the apparatus used for the condensation experiments. The developed tests could successfully provide a rapid estimation of the coating's durability during a broad range of liquid-vapour phase change applications.

This study aims to analyze the individual and combined chemical attacks of sulfate and chloride ions on cementitious materials and assess the efficiency of some selected additives (fly ash, blast furnace slag, and metakaolin) in countering this combined attack. This research is conducted in the context of construction in marine environments, where reinforced concrete structures are often subject to significant challenges due to early exposure to sulfate and chloride ions. This early exposure results in concrete expansion, cracking, and, ultimately, the corrosion of steel reinforcements. Nevertheless, the interaction between sulfate ions, chloride ions, and the cementitious matrix remains poorly understood. Previous research has drawn conflicting conclusions, with some suggesting that sulfate ions mitigate chloride attacks, while others have come to the opposite conclusion. During this study, experimental investigations were conducted by immersing powders obtained from crushed ordinary Portland cement (CEM I) paste specimens, as well as binary, ternary, and quaternary blends, in sulfate, chloride, and sulfate–chloride solutions over the course of 25 days at an early age. Results from different characterization techniques (thermogravimetric analysis, Fourier Transform Infrared spectroscopy, Raman spectroscopy, etc.) indicate that chloride ions delay the formation of ettringite, while the presence of sulfate ions accelerates the chloride attack by limiting the formation of Friedel’s salt. The Mercury Intrusion Porosimetry test confirmed these results by showing a pronounced increase in specimens’ porosity after exposure to solely sulfate after 25 days, compared to the ones exposed to both sulfate and chloride ions. Furthermore, the incorporation of multiple additives, particularly in ternary and quaternary blends, demonstrates the enhanced durability of the studied samples. This was confirmed by a Fourier Transform Infrared spectroscopy analysis, which indicated a delayed ettringite formation in these mixtures. This delay was further affirmed by the complete depletion of sulfate ions in the sulfate solutions upon contact with powders derived from the 100% CEM I paste.

Developing durable oxygen reduction reaction (ORR) electrocatalysts is essential to step up the large-scale applications of proton exchange membrane fuel cells (PEMFCs). Traditional ORR electrocatalysts provide satisfactory activity, yet their poor durability limits the long-term applications of PEMFCs. Porous carbon used as catalyst support in Pt/C is vulnerable to oxidation under high potential conditions, leading to Pt nanoparticle dissolution and carbon corrosion. Thus, integrating Pt nanoparticles into highly graphitic mesoporous carbons could provide long-term stability. This Perspective seeks to reframe the existing approaches to employing Pt alloys and mesoporous carbon-integrated ORR electrocatalysts to improve the activity and stability of PEMFCs. The unusual porous structure of mesoporous carbons promotes oxygen transport, and graphitization provides balanced stability. Furthermore, the synergistic effect between Pt alloys and heteroatom doping in mesoporous carbons not only provides a great anchoring surface for catalyst nanoparticles but also improves the intrinsic activity. Furthermore, the addition of Pt alloys into mesoporous carbon optimizes the available surface area and creates an effective electron transfer channel, reducing the mass transport resistance. The long-term goals for fuel-cell-powered cars, especially those designed for heavy-duty use, are well aligned with the results shown when this hybrid material is used in PEMFCs to improve performance and durability.

Proton exchange membrane fuel cells (PEMFCs) face technical issues of performance degradation due to catalyst dissolution and agglomeration in real-world operations. To address these challenges, intensive research has been recently conducted to introduce additional structural units on the catalyst surface. Among various concepts for surface modification, carbon shell encapsulation is known to be a promising strategy since the carbon shell can act as a protective layer for metal nanoparticles. As an interesting approach to form carbon shells on catalyst surfaces, the precursor ligand-induced formation is preferred due to its facile synthesis and tunable control over the carbon shell porosity. However, the origin of the carbon source and the carbon shell formation mechanism have not been studied in depth yet. Herein, this study aims to investigate carbon sources through the use of different precursors and the introduction of new methodologies related to the ligand exchange phenomenon. Subsequently, we provide new insights into the carbon shell formation mechanism using X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). Finally, the thermal stability and electrochemical durability of carbon shells are thoroughly investigated through in situ transmission electron microscopy (in situ TEM) and accelerated durability tests.

In this study, a reinforced geosynthetic cementitious composite mat (GCCM) with improved structural stability and reinforcement efficiency through yarn-in-lay technology was designed and manufactured. Additionally, a blowing agent was added to relax the cross-sectional reduction caused by the rapid curing and shrinkage for reduction of installation period. The impact resistance results showed a significant increase compared to the pre-reinforcement values. Through the analysis of blowing agent content, concrete filling ratio, and bending strength of the double raschel GCCM, optimal conditions were determined. Therefore, the double raschel GCCM showed improved flexural strength even after a short curing period of 10 days, along with excellent durability under environmental conditions.

Nowadays, durable protective coatings receive more attention in the field of conservation for several reasons (they are cost effective, time consuming, more resistance, etc.). Hence, this study was focused on producing a multi-functional, durable coating to protect different stone materials, especially, Lecce stone, bricks, and marble. For this purpose, ZrO2-doped-ZnO-PDMS nanocomposites (PDMS, polydimethylsiloxane used as the binder) were synthesized by in situ reaction (doped nanoparticles were inserted into the polymer matrix during the synthesis of PDMS) and the performances of resulting coatings were examined by handling different experimental analyses. In particular, the study aimed to evaluate the durability properties of the coating along with the self-cleaning effect. As a result, the durability of the nanocomposite coating with respect to the well-known PDMS coating was assessed after exposure to two different ageing cycles: solar ageing (300 W, 1000 h) and humid chamber ageing (RH > 80%, T = 22 ± 3 °C, desiccator, 2 years). All the results were in good agreement with each other providing that newly prepared nanocomposite coating can be used as a durable protective coating for different stone materials.

Transparent superhydrophobic coatings have been extensively investigated due to their ability to provide self-cleaning properties for outdoor applications. However, the widespread implementation of these coatings on a large scale is impeded by the challenges of poor durability and complex fabrication procedures. In this review, the fundamentals and theories governing the mutually exclusive properties of superhydrophobicity, optical transparency, and susceptibility to wear are introduced, followed by a discussion of representative examples of advanced surface design and processing optimizations. Also, robust evaluation protocols for assessing mechanical and chemical stabilities are briefed and potential research directions are presented. This review can offer the research community a better understanding of durable and transparent superhydrophobic surfaces, thereby facilitating their development for real-world applications.

The purpose of this study is to examine the effects of partially replacing cement with a blend of marble waste powder (MWP) and granite waste powder (GWP) in mortar, with the goal of reducing the environmental harm caused by cement. The investigation included an analysis of the distinctive properties of the two waste powders individually, as well as initial tests with various ratios to determine the optimal combination that yields the highest strength. It was observed that a 50% MWP to 50% GWP blend produced the most substantial strength. Subsequently, the effect of partial replacement of cement with the blend of marble and granite waste powder (MGWP) at various increments of 5%, ranging from 0% to 30%, was evaluated by subjecting the mortar to numerous tests to assess its workability, physical, mechanical, durability, and microstructural properties. The analysis of the employed waste powders confirmed that the GWP can be classified as a natural pozzolan material belonging to Class N. As the proportion of MGWP increased, the workability of the mortar mixes decreased. However, incorporating MGWP up to 15% resulted in enhancements in bulk density, compression strength, and homogeneity, with the best performance observed at a 10% MGWP content. Microstructure analysis confirmed that the addition of MGWP enhanced the bonding of C–S–H and C–H, leading to a denser morphological structure in the mixes, particularly at a 10% MGWP content. The utilization of MGWP not only significantly reduced the carbon footprint associated with cement production but also fostered sustainability.

Concrete as a building material is susceptible to degradation by environmental threats such as thermal diffusion, acid and sulphate infiltration, and chloride penetration. Hence, the inclusion of nanomaterials in concrete has a positive effect in terms of promoting its mechanical strength and durability performance, as well as resulting in energy savings due to reduced cement consumption in concrete production. This review article discussed the novel advances in research regarding C-S-H gel promotion and concrete durability improvement using nanomaterials. Basically, this review deals with topics relevant to the influence of nanomaterials on concrete’s resistance to heat, acid, sulphate, chlorides, and wear deterioration, as well as the impact on concrete microstructure and chemical bonding. The significance of this review is a critical discussion on the cementation mechanism of nanoparticles in enhancing durability properties owing to their nanofiller effect, pozzolanic reactivity, and nucleation effect. The utilization of nanoparticles enhanced the hydrolysis of cement, leading to a rise in the production of C-S-H gel. Consequently, this improvement in concrete microstructure led to a reduction in the number of capillary pores and pore connectivity, thereby improving the concrete’s water resistance. Microstructural and chemical evidence obtained using SEM and XRD indicated that nanomaterials facilitated the formation of cement gel either by reacting pozzolanically with portlandite to generate more C-S-H gel or by functioning as nucleation sites. Due to an increased rate of C-S-H gel formation, concrete enhanced with nanoparticles exhibited greater durability against heat damage, external attack by acids and sulphates, chloride diffusion, and surface abrasion. The durability improvement following nanomaterial incorporation into concrete can be summarised as enhanced residual mechanical strength, reduced concrete mass loss, reduced diffusion coefficients for thermal and chloride, improved performance against sulphates and acid attack, and increased surface resistance to abrasion.

To study the durability of proton exchange membrane fuel cells (PEMFCs), the experiments were performed by using a 300 h accelerated stress test under vibration and non-vibration conditions. Before and after chronic operation, the polarization curve, impedance spectra and cyclic voltammogram were measured at regular intervals. The voltage under vibration shows a small decline at the current density of 400 mA cm−2 and decreases quickly along the time in high current density. Meanwhile, the pavement vibration dramatically impacts the contact resistance of the membrane electrode assembly to the bipolar plates and the clamping screws of the fuel cell easily loosen under vibration. The calculations from X-ray diffraction patterns indicate that the average diameters of Pt particles under vibration are smaller than those under no-vibration conditions. It increases from 3.17 nm in the pristine state to 3.43 nm and 4.62 nm, respectively. Moreover, much more platinum that dissolved from the catalyst layer and redeposited was detected inside the polymer membrane under vibration conditions.

This article expounds on the problem of the use of de-icing salts in the corrosion of steel rebars in bridge decks and their effect on post-tensioning elements. In particular, this paper focuses this problem on structures affected by an aggregate–alkali reaction and without any waterproof treatment using the example of one structure whose repair was carried out in 2020. In this structure, the internal stresses due to the aggregate–alkali reaction caused longitudinal cracks in the upper face of the deck, through which the penetration of chloride ions was concentrated, causing, finally, the brittle fracture of the steel bars and the corrosion of the prestressing elements. This article also explains some conclusions about the most probable mechanisms that resulted in the brittle fracture of the steel bars due to the extraordinary and unexpected nature of this phenomenon.

There is a large amount of oil-contaminated wastewater caused by oil/gas production and marine oil spills. It is still a major challenge for the development of oil/water separating membranes that have excellent separation efficiency, can withstand saline environments, and have long-term durability. We present a new membrane made of ultralong titanate nanofibers (TNF) (with diameter of 200 nm and length of 60 µm) and carbon nanofibers (CNF) (with a diameter of 150 nm and length of 50 µm) for efficient and consistent oil/saltwater separation. The intertwined structure of titanate and carbon nanofibers is critical to ensuring a high mechanical strength and durability for the new membrane. The carbon nanofiber works as a scaffold in this membrane to maintain mechanical integrity during multiple cycles of reuses, which is an important merit for its practical applications. The ultralong titanate nanofibers work as functional component to provide high hydrophilicity of the membrane. The new membrane has an oil/water separation efficiency of more than 99%, an oil content in treated effluent that is lower than US environmental discharge standards (42 ppm), and a high water flux of 1520 LMH/bar, due to its excellent superhydrophilicity and inter-connected pore structure. The new membrane also exhibits outstanding durability in a variety of salinity environments, as well as good resistance to oil fouling. This new type of membrane has a high potential for industrial application in treating oily wastewater due to its excellent environmental durability, oil-fouling resistance, high separation efficiency, and easy scalability.

Massive growth in the infrastructure industry and development has led to a phenomenal increase in cement usage. The cement industry emits the greenhouse gas (CO2) and cement production requires more embodied energy. There is an increasing research interest in geopolymers (GP) for developing an alternate binder for civil engineering applications because of its low energy consumption and eco-friendly nature. GP contain alkali-activated material, which is relatively new, and Geopolymer concrete (GPC) has superior mechanical and durability properties compared to ordinary Portland cement (OPC) concrete. The objective of the review article is to make all-encompassing review of long-term (LT) and short-term (ST) properties of GP, their chemistry, reaction mechanism, effect of reaction parameters, fresh properties, stability under elevated temperature exposure, bond between steel and reinforcement and various field implementations. It is concluded that GPC can achieve structural grade strength when different industrial waste materials as precursors are used in its preparation by varying the alkaline concentration, curing method and curing temperature. It is also concluded that GP gives better thermal resistance at elevated temperature exposure up to 1000 °C whereas OPC fails. Various research and development works carried out in India by utilising the locally available industrial waste-based source materials are also discussed. Applications of GP technology in current scenario have also been reviewed. The gap in GP technology pertaining to corrosion, carbonation and leaching effects of GPC need to be focussed in future research.

In this study, we analyzed the durability of the commercial Pt/C catalysts with platinum loading of 20% and 40% using two different accelerated durability tests, i.e., using Ar or O2 when bubbling the electrolyte during testing. The structural analysis of the changes in the morphology of the catalysts was performed by XRD and TEM as well as the assessment of the degradation degree of the catalysts using the values of the specific surface area and ORR activity, both, before and after the stress testing. Regardless of the stress testing conditions, the JM20 material was established to degrade ESA and the catalytic activity to a greater extent than JM40, which may be due to the structural and morphological features of the catalysts and their evolution during the stress testing under various conditions. The JM20 material has been reported to exhibit a greater degree of degradation when bubbling the electrolyte with oxygen during the stress testing compared to argon, which may be explained by a different mechanism of degradation for the catalyst with the predominant oxidation of the carbon support, leading to a different nature of the distribution of the platinum nanoparticles over the surface of the carbon support, according to results that have estimated the number of nanoparticle intersections.

This study analysed the condition of the surface layer of valve stems made of 317Ti steel after polishing and burnishing. Surface roughness, microhardness, and residual stress tests were carried out. The tests were carried out to determine the effect of the condition of the surface layer (especially non-standard parameters of surface roughness) of the stems on the durability of valves and to determine the possibility of obtaining a favourable state by means of sliding burnishing. Significant differences were observed in the values of the roughness parameters that determine the tribological properties of the surface, and higher surface microhardness and residual compressive stresses were obtained after burnishing. The durability of the stem-graphite seal in a reciprocating movement was tested, and the failure-free operation time of valves with burnished stems was approximately four times longer, which is the premise for recommending sliding diamond burnishing as a finishing treatment for valve stems.

The service environment of concrete in the marine environment is harsh, and demands regarding the durability of marine concrete have increased. Marine concrete in harbor and wharf areas suffers from the combined effect of fatigue load, dry–wet cycles, and Cl− erosion, which can result in spalling of the concrete surface, corrosion of the internal reinforcement, and even concrete damage. This paper reviews recent research results on the durability of concrete and reinforced concrete (RC) under the combined effect of fatigue load, dry–wet cycles, and Cl− erosion. We further assess the variation in Cl− transport properties with fatigue load, the causes behind the reduction in the carrying capacity of RC products under fatigue load, the methods of Cl− erosion on concrete under the pressures imposed by dry–wet cycles, and the damage of the protective layer of concrete due to accelerated Cl− erosion caused by the action of dry–wet cycles. Further studies are needed on the durability of concrete under the action of fatigue load, wet and dry cycles, and Cl− erosion, in addition to the testing of the durability of concrete under the combined effects of the afore-mentioned various factors.

This study investigated the impact of using cow dung ash (CDA) as a partial replacement for ordinary Portland cement (OPC) in mortar. Mortar mixes are prepared by replacing OPC with CDA at varying levels: 5%, 10%, 15%, 20%, 25%, and 30%. The chemical composition of CDA shows that it is composed primarily of SiO2, Al2O3, and Fe2O3, with a significant amount of loss of ignition. The workability, hardened properties, and microstructure of CDA-containing mortars are also analyzed. The increasing CDA content in mortar reduces workability and, beyond 5%, it causes high water absorption due to CDA’s porous nature and unremoved organic compounds. This impacts the density and compressive strength of the hardened mortar as well as compromising its homogeneous characteristics. When using 5% CDA, the bulk density and compressive strength of the mortar are comparable to those of the control mixes. Nonetheless, as the proportion of CDA increases, both the bulk density and compressive strength of the mortar diminish. The thermal stability of mortar mixes with 10%, 20%, and 30% CDA is unaffected at temperatures between 500 °C and 600 °C. The Fourier-transform infrared spectroscopy (FTIR) analysis reveals the presence of unreacted particles and wide stretched C–S–H gels in the mortar samples. In general, the results suggest that CDA can be utilized as a substitute for OPC at a ratio of up to 10% in the manufacturing of mortar and can serve as a feasible alternative cementitious material.

Walnut shells can be used as fuels in power plants directly or as biochars obtained by pyrolysis or torrefaction. They are an example of clean waste biomass which shows a low ash content and a high Net Calorific Value, making them excellent for energy recovery in industrial and non-industrial applications, such as in bakeries, restaurants, and homes. Their main inconvenience is their low bulk density. Densification is a possible solution that reduces the costs of transportation, handling, and storage. In this work, after the characterization of the walnut shells, briquettes were obtained using a hydraulic piston press briquette machine under different conditions to find the best quality without the need for previous grinding for pelletizing. This method features easy operation and maintenance, and the briquette shape could be adapted as desired. The quality of the briquettes was measured through their density and durability. After fixing a compaction pressure to obtain acceptable briquettes, the factors affecting their quality were studied: operating temperature, moisture content, and the presence of small amounts of walnuts. Good quality briquettes were obtained with a compaction pressure of 66 MPa, with densities around 1040 kg/m3, and durabilities higher than 94% when the process was carried at 140 °C. The greatest increase in durability was observed between briquettes obtained at room temperature and those obtained at 80 °C. The presence of small amounts of walnuts, common after the shelling process, improved the durability. Although water is necessary, briquettes obtained from biomass with only 1% of moisture showed better durabilities. Therefore, walnut shells are suitable for obtaining good quality briquettes according to the specifications of solid biofuels established in the standards, without the need for any pretreatment.

Epoxy adhesives, widely used in multiple structural applications, are used in the milling tool industry to replace brazing and mechanical fastening when joining the cutting bits to the tool body; though their durability is still a concern. This work aims to evaluate and characterise the effect of environmental factors associated with a tool’s life cycle on the performance of these bonded joints. A gravimetric analysis was conducted on bulk adhesive plates for water, cutting emulsion and dielectric fluid to obtain diffusion and relaxation rates. Novel real joint shear specimens were developed to enable strength testing on joints which are comparable with the final application. These specimens were immersed in fluids and subjected to thermal cycles or a corrosive finishing surface treatment to simulate the tool’s life cycle. The joint’s resistance was then benchmarked. Lastly, a dimensional variation test was carried out on tool prototypes before and after ageing, showing no significant dimensional variation which could compromise the cutting performance of the tool. Overall, though it was possible to identify a decrease in strength of around 20% in most tests, joint strength was still within the values necessary for safe operation, with a large safety factor still being retained.

Along the Portuguese coastline, several military fortifications were built with the intention to protect the territory from the constant military threat from the sea. These constructions have been subjected, during centuries, to a very aggressive environment; the renders, whose main function is the protection of walls, are particularly exposed to such actions. Nossa Senhora dos Anjos de Paimogo’s Fort, better known as the Paimogo’s Fort, is one of these fortifications, built in 1674 and classified of public interest since 1957. Within the scope of the “Coast Memory Fort” Project of EEA Grants Culture Programme 2014–2021, promoted by the Municipality of Lourinhã, repair mortars are being developed for the preservation of the Fort, considering the physical–mechanical and chemical characteristics of the pre-existing mortars and of the substrate, as well as the aggressive environmental conditions. In this work, several mortar compositions, compatible with the original mortars and designed to resist the aggressive environment, are briefly described and their main physical and mechanical characteristics are analysed and compared in successive ages. Different binder mixes were used, and a fine-tuning of the aggregate was carried out. Assessment of sequential wetting/drying cycles’ effect on the mortar’s behaviour is also presented. The laboratory results reveal that mortars with additions of 30% of quicklime present the best behaviour (with the lowest water absorption and highest strength). Moreover, the substitution of part of the siliceous sand by limestone aggregate, in general, increases the mortars’ mechanical strength; however, the drying occurs slower, which could compromise the durability of these mortars if a good balance is not achieved.

Despite the fast-developing momentum of perovskite solar cells (PSCs) toward flexible roll-to-roll solar energy harvesting panels, their long-term stability remains to be the challenging obstacle in terms of moisture, light sensitivity, and thermal stress. Compositional engineering including less usage of volatile methylammonium bromide (MABr) and incorporating more formamidinium iodide (FAI) promises more phase stability. In this work, an embedded carbon cloth in carbon paste is utilized as the back contact in PSCs (having optimized perovskite composition), resulting in a high power conversion efficiency (PCE) of 15.4%, and the as-fabricated devices retain 60% of the initial PCE after more than 180 h (at the experiment temperature of 85 °C and under 40% relative humidity). These results are from devices without any encapsulation or light soaking pre-treatments, whereas Au-based PSCs retain 45% of the initial PCE at the same conditions with rapid degradation. In addition, the long-term device stability results reveal that poly[bis(4–phenyl) (2,4,6–trimethylphenyl) amine] (PTAA) is a more stable polymeric hole-transport material (HTM) at the 85 °C thermal stress than the copper thiocyanate (CuSCN) inorganic HTM for carbon-based devices. These results pave the way toward modifying additive-free and polymeric HTM for scalable carbon-based PSCs.

The reliability of furniture constitutes one of the most important features taken into consideration when buying furniture. However, to evaluate furniture reliability, furniture manufacturers often rely on their own experiences and common patterns without the usage of specialized tools. The presented work aimed to develop a mathematical apparatus to be used in a specially created web application that would enable the calculation of the reliability of the selected furniture joints and whole case furniture structures. This paper describes the functionality features of the newly created web application, which could be used in the furniture industry practice providing a valuable support tool for engineering works. In this paper, the reliability calculations are presented for the examples of furniture eccentric joints and case-type furniture made of those joints. Two different materials, namely MDF and laminated three-layer particleboard, of 18 mm are considered. The achieved results confirm the higher reliability of the furniture eccentric joints made of MDF of 18 mm in comparison to the furniture eccentric joints made of particleboard of the same thickness. The calculations of reliability for the analyzed construction of furniture confirmed also that the reliability improved when the parallel reliability structure was adapted. That was the case for both the MDF and laminated three-layer particleboard.

The conveyor belt is by its structure a textile composite. As a load-supporting element of the conveyor, the belt withstands variable loads during its operations. In order to investigate the influence of the level and variability of loading on the life of the belt, tests were carried out on specimens in laboratory conditions. A testing device was specially designed and made for these tests that enabled precise control and monitoring of the loading as well as number of loading cycles up to fracture. This research provides an overview of the influence of fatigue loading on the fatigue life of the belt. The methodology of the conducted research is explained with a description of important technical parameters of the testing device. A physical experiment and a corresponding numerical simulation using the FEM method were carried out with multiple loading levels of belt specimens. Based on the obtained results, appropriate conclusions were made; at loads less than 70% of the breaking strength, the lifetime of the belt is very long. Attention was drawn to additional influences that could not be covered by the experiment and possible directions for further research were indicated.

A facile one-pot hydrothermal method has been demonstrated for the fabrication of an innovative hydrangea-like NiSe/FeSe2 nanocatalyst for boosting oxygen evolution reaction (OER). Benefitting from the advantages of the porous architecture, high specific surface area, facilitated electron transfer rate, an ultralow overpotential of merely 210 mV is required for the optimized NiSe/FeSe2(1:1.5) to drive the electrocatalytic water oxidation to reach to 10 mA cm−2. Moreover, by equipping NiSe/FeSe2(1:1.5) with Pt/C for electrochemical water splitting, a cell potential of merely 1.60 V is demanded to attain 10 mA cm−2, even outperforming the IrO2 ‖ Pt/C couple. More importantly, the structure and morphology of NiSe/FeSe2(1:1.5) are still well maintained after a long-term chronopotentiometry test. This work opens a new avenue for constructing effective and durable non-precious electrocatalysts for OER.

The polymer demand for geotechnical applications has been growing. The geomembrane is a geosynthetic, manufactured, polymeric product and is often specified in environmental projects. Geomembranes started to be used in the 1930s but became more widespread in the 1940s. In the 1970s, geomembranes began to be specified for landfills. Over the past forty years, millions of square meters of HDPE geomembrane have been used in different applications. One of the most important issues for HDPE geomembranes is durability, involving very long-term property requirements. A rupture in the liner that has a geomembrane may provide losses in terms of human lives, environmental impacts, and financial costs. This paper summarizes the mechanisms and concepts involved in the HDPE geomembrane aging and describes the important contributions of laboratory and field studies over the years around the world. Different conditions and exposures drive the HDPE geomembrane behavior, including field temperature conditions and contact with different chemical substances. Accelerated laboratory testing with HDPE geomembrane simulating field boundary conditions is critical to ensure proper use of this geosynthetic in the future.

Climate change is affecting every being on the planet. The time has arrived to give a big push for harvesting renewable energy sources, thus reducing the dependencies on fossil fuels and chemical batteries. This inspired Nanotechnologists to explore energy harvesting techniques from the environment. Triboelectric nanogenerator (TENG) is one such emerging, promising, and a reliable technology to extract micropower from the abundantly available natural mechanical energy. In this study, we have addressed the durability issues of TENG using Diamond-like Carbon (DLC) films as a triboelectric surface. Our findings indicate a high potential for DLC films for TENG applications attributing to its outstanding tribological, mechanical and insulating properties. Hydrogenated DLC (H-DLC) film, Fluorinated DLC (F-DLC) film, and PTFE were used as dielectric surfaces on a rotary based sliding-TENG. The output performance of each pair differed with the sliding frequency where H-DLC/F-DLC pair produced the maximum output at a moderate frequency of 4 Hz. As the frequency was raised, H-DLC/PTFE pair exhibited the highest output at 10 Hz, equal to that of the Al/PTFE pair. The durability evaluation of DLC-TENG showed very promising outcomes producing stable output current for 2 h. This study is expected to encourage the development of DLC-based sliding-TENGs, with enhanced durability and output efficiency.

The development of a novel artificial heart valve with outstanding durability and safety has remained a challenge since the first mechanical heart valve entered the market 65 years ago. Recent progress in high-molecular compounds opened new horizons in overcoming major drawbacks of mechanical and tissue heart valves (dysfunction and failure, tissue degradation, calcification, high immunogenic potential, and high risk of thrombosis), providing new insights into the development of an ideal artificial heart valve. Polymeric heart valves can best mimic the tissue-level mechanical behavior of the native valves. This review summarizes the evolution of polymeric heart valves and the state-of-the-art approaches to their development, fabrication, and manufacturing. The review discusses the biocompatibility and durability testing of previously investigated polymeric materials and presents the most recent developments, including the first human clinical trials of LifePolymer. New promising functional polymers, nanocomposite biomaterials, and valve designs are discussed in terms of their potential application in the development of an ideal polymeric heart valve. The superiority and inferiority of nanocomposite and hybrid materials to non-modified polymers are reported. The review proposes several concepts potentially suitable to address the above-mentioned challenges arising in the R&D of polymeric heart valves from the properties, structure, and surface of polymeric materials. Additive manufacturing, nanotechnology, anisotropy control, machine learning, and advanced modeling tools have given the green light to set new directions for polymeric heart valves.