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Precise micropatterning on three-dimensional (3D) surfaces is desired for a variety of applications, from microelectronics to metamaterials, which can be realized by transfer printing techniques. However, a nontrivial deficiency of this approach is that the transferred microstructures are adsorbed on the target surface with weak adhesion, limiting the applications to external force-free conditions. We propose a scalable photolithography-transfer-plating method to pattern stable and durable microstructures on 3D metallic surfaces with precise dimension and location control of the micropatterns. Surface patterning on metallic parts with different metals and isotropic and anisotropic curvatures is showcased. This method can also fabricate hierarchical structures with nanoscale vertical and microscale horizontal dimensions. The plated patterns are stable enough to mold soft materials, and the structure durability is validated by 24 h thermofluidic tests. We demonstrate micropatterned nickel electrodes for oxygen evolution reaction acceleration in hydrogen production, showing the potential of micropatterned 3D metallic surfaces for energy applications.

The surface engineering of electrocatalysts is one of the promising strategies to increase the intrinsic activity of electrocatalysts. It generates anion/cation vacancy defects and increases the electrochemically active surface area. We describe the surface engineering of Ni2P to favorably tune the bifunctional oxygen electrocatalytic activity and the development of a rechargeable zinc‐air battery (ZAB). Ni2P encapsulated with N and P‐dual doped carbon (Ni2P@NPC) is synthesized using a single‐source precursor complex tris‐(2,2′‐bipyridine)nickel(II) bis(hexafluorophosphate). The surface engineering of the as‐synthesized Ni2P@NPC catalyst is achieved by the controlled acid treatment at room temperature. The surface engineering removes the carbon debris and opens the pores, exfoliates the encapsulating carbon layer, increases the P‐vacancy in the crystal lattice, and boosts the electrochemically active surface area. The surface‐engineered catalyst exhibits enhanced bifunctional activity towards oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The electrocatalytically active sites of engineered catalysts are highly accessible for facilitated electron transfer kinetics. P‐vacancy favors the facile formation of defect‐rich OER active metal oxyhydroxide species. The rechargeable ZAB based on the engineered catalyst delivers a specific capacity of 770.25 mA h gZn−1, energy density of 692 Wh kgZn−1, and excellent charge‐discharge cycling performance with negligible voltaic efficiency loss (0.6 %) after 100 h. [ABSTRACT FROM AUTHOR]

Integration of hydrophobic and antibacterial functionalities into polyester‐cotton blended (PTCO) textiles has attracted more attention but remains a challenge. Here, a Janus fabric with antibacterial effect, hydrophobicity, and enhanced moisture‐permeability is fabricated using a "mist polymerization" approach. The PET fibers in the PTCO fabric are amino‐functionalized through ammonolysis reactions of PET molecules with HDA, and mist treatments of poly lauryl methacrylate (PLMA) and poly(DMC‐co‐MA) (PDM) are applied on the two side surfaces of the PTCO‐HDA fabric, respectively. The resulting Janus fabric exhibits an antibacterial rate of 99.9% against both E. coli and S. aureus, along with a hydrophobic property on its single side (PTCO‐HDA@PLMA). Additionally, the establishment of a surface‐free energy gradient across the fabric confers superior moisture‐permeability to the Janus fabric, offering advantages in preserving textile comfort. Moreover, this approach does not significantly compromise the original fabric properties, such as mechanical strength, moisture permeability, and fabric softness. The proposed method offers a straightforward and scalable strategy for textile finishing, demonstrating great potential in expanding the application scope of PTCO fabrics, and it may hold a pivotal role in diverse applications, notably encompassing home textiles, wound dressings, and high‐performance sportswear. [ABSTRACT FROM AUTHOR]

Reduced wear and friction are directly related to longer component service lives and increased energy efficiency. The mechanisms used to achieve this goal in mechanical systems include the study of lubricant chemistry, surface coating, and surface modification. Significant research has been conducted on friction reduction of valve trains of internal combustion engines using surface modifications such as coatings and surface texturing. Here, an experimental approach has been adopted to investigate the effect of micro surface texturing on Thermo-Elastohydrodynamically Lubricated cam/tappet contact in a direct-acting valve train. A commercial vehicle valve train has been instrumented to study the effect of varying surface texture area density on friction under realistic engine operating conditions. Fiber laser surface texturing has been used to microtexture three samples of tappet shims with texture densities of 5%, 8%, and 10%. The tests have been run at four engine speeds—300, 500, 700, and 900 RPM—and three temperatures—30 °C, 60 °C, and 90 °C. The experimental results show a significant friction reduction of up to 18.33% for textured shims at the temperature of 90 °C. The friction reduction performance of the 8% textured shim has been optimum for all RPMs at the higher temperatures. [ABSTRACT FROM AUTHOR]

This review highlights recent advancements in stabilizing perovskite-quantum dots (PQDs) for biomedical applications. PQDs like CsPbBr3 nanoparticles are promising due to their high photoluminescence-quantum yield, narrow emission linewidth, and ability to control excitation and emission wavelengths, making them suitable for bioimaging and sensing applications. However, their instability in moist and aqueous environments and potential toxicity due to heavy metals like lead pose significant challenges. To address these issues, various surface-modification strategies, including encapsulation, ligand exchange, and phase transfer, have been developed. These methods aim to improve PQD stability and biocompatibility while preserving their optical properties. Encapsulation techniques using polymers, silica, and phospholipids have shown promise in maintaining PQD stability in aqueous solutions. Ligand-exchange strategies with multidentate and multifunctional ligands have enhanced PQD surface binding and hydrophilicity, improving their environmental robustness. Applications such as fluorescence cellular imaging, theragnostics, and immunoassays demonstrate the potential of stabilized PQDs in biomedical applications. Despite these advancements, further research is needed to develop non-toxic PQDs and ensure long-term stability. Continued progress in PQD synthesis and surface modification could lead to significant breakthroughs in biomedical research and clinical diagnostics. [ABSTRACT FROM AUTHOR]

Air‐processed perovskite solar cells are desirable for the large‐scale manufacturing application in the future, yet the presence of moisture and oxygen goes against perovskite crystallization and deteriorates phase stabilization, leading to the formation of substantial defective nano‐impurities, especially on the vulnerable surface. Here, we propose a strategy to simultaneously remove superficial defect layer and solidify the surface by soaking air‐fabricated perovskite film into low‐polar organic esters at elevated temperature to trigger an in situ dynamic surface lattice disassemble and reconstruction process. Molecular dynamics simulations and experimental results indicate that the inorganic CsPbI2Br perovskite is first dissolved and then the Br‐rich phase is recrystallized at solid–liquid interface owing to the balance between weak solubility and high‐temperature induced annealing process, thus hardening the soft surface and releasing the lattice tensile stress, which benefits the minimization of interfacial recombination and improvement of the structural stability. As a result, we prepare a carbon‐based CsPbI2Br device in complete air without precise control on humidity, achieving a champion efficiency of 15.37 % with excellent resistance to harsh attackers. This method offers a promising avenue for overcoming the limit of processing conditions on advancing perovskite‐based optoelectronic devices. [ABSTRACT FROM AUTHOR]

Many of the functions and features of practically useful materials are the province of molecular‐level chemistry and their modulation at different length‐scale. This report illustrates the molecular‐level chemistry behind functions and features of the [2.2]paracyclophane‐based materials with a particular focus on the most recent explorations on through‐space conjugated small‐molecule organic emitters, π‐stacked macrocyclic molecules and polymers, poly(p‐phenylenevinylene)s featuring well‐defined donor‐acceptors sequence control, and surface engineering of technologically‐relevant parylenes that finds broad applications across the field of chemical science and technology. This report largely deals with the potential and opportunities associated with molecular features and functions of planar chirality, conformational behaviors, strain‐induced non‐planarity of the aromatics, the profound impacts of through‐space conjugation and π‐electron interactions/delocalization on optoelectronic properties of the π‐conjugated organic emitters, polymers and extended structures consisting of cyclophanes. A special focus is put on the concept of supramolecular polymers using chemically‐programmed chiral cyclophanes via non‐covalent stacking and controlled conformational arrangements. Illustrating cyclophane as precursors/monomers and fabrication strategies for their incorporation in structurally‐controlled (poly(p‐xylylene)s formed via chemical vapor deposition polymerization and post‐deposition fabrication for interface engineering is described. Demonstrating a rather different approach of electronically‐dictated ring‐opening metathesis polymerization employing strained cyclophane‐diene precursors that generate conjugated poly(p‐phenylenevinylene)s with well‐defined (i.e., low dispersity) and donor‐acceptor sequence control is also discussed. This report will serve as an indispensable one‐stop reference for organic, and polymer chemists, as well as material scientists working with cyclophanes for research innovations. [ABSTRACT FROM AUTHOR]

Transparent flexible display devices have attracted massive attention in recent years owing to their practical applications that can be compatibly adapted to human demand and technological development. Worldwide researchers have studied flexible transparent thin film transistors (TFTs) to qualify them for the backplane component of future transparent and flexible displays. Simplifying the fabrication process of a TFT can be considered a critical need for reducing consumed cost, time, toxic chemicals. In this study, sputtering was utilized as a major fabrication method for manufacturing a transparent oxide TFT device, which demonstrated good mechanical flexibility. A simple surface treatment process was applied to enhance the susceptibility of the sputtered Al 2 O 3 dielectric through multiple coatings of solution processed Al 2 O 3. It is noteworthy that the transparent oxide TFT device exhibits a high optical transparency of 81.12% and good electrical switchability at low operating voltage (3 V) with a decent mobility of 4.37 cm2 V−1 s−1 and proven mechanical durability. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) semiconductors with unique structures and surface physicochemical characteristics have been extensively employed for efficient photocatalysis. Recently, surface coordination activation interactions have obtained attention in promoting photocatalytic efficiency as they establish bridges between reactants and photocatalysts. Accordingly, a burgeoning trend in the design of 2D photocatalysts is regulating the surface active centers for coordinating with reactants. These attempts have developed various effective strategies to optimize the 2D photocatalysts and provide in‐depth insights into the structure‐function relationship for heterogeneous photocatalysis. Herein, we summarize recent advances in surface engineering in designing efficient 2D photocatalysts, focusing on coordination activation. We emphasize the advantages of coordination activation as a versatile medium for engineering the surface of photocatalysts. In particular, the discussion includes various strategies for surface engineering and the structure‐function relationship in photocatalysis. This work systematically concludes the significance and future challenges of coordination activation in the surface functionalization of 2D photocatalysis, shedding light on the design of next‐generation photocatalysts. [ABSTRACT FROM AUTHOR]

Crystallization fouling, a process where mineral scales form on surfaces, is of broad importance in nature and technology, negatively impacting water treatment and electricity production. However, a rational methodology for designing materials with intrinsic resistance to scaling and scale adhesion remains elusive. Here, guided by nucleation physics, this work investigates the effect of coating composition and surface structure on the nucleation and growth mechanism of scale on metallic heat transfer surfaces nanoengineered by large‐area techniques. This work observes that on hydrophilic nanostructured copper, despite its significantly enlarged surface area compared to smooth surfaces, scale formation is substantially suppressed leading to sustained, efficient cooling performance. This work reveals the mechanism through thermofluidic modeling coupled with in situ optical characterization and show that surface bubble formation through degassing is responsible for generating local hot spots enhancing supersaturation. This work then demonstrates a scalephobic nanostructured surface which reduces the accumulated surface scale mass 3.5× and maintains an 82% higher heat transfer coefficient compared to superhydrophobic surfaces with corresponding energy conversion savings. This work not only advances the understanding of fouling mechanisms but also holds promise for practical applications in industries reliant on efficient heat transfer processes. [ABSTRACT FROM AUTHOR]

Surface engineering is one of the most extensive industries. Virtually all areas of the economy benefit from the achievements of surface engineering. Surface quality affects the quality of finished products as well as the quality of manufactured parts. It affects both functional qualities and esthetics. Surface quality affects the image and reputation of a brand. This is particularly true for cars and household appliances. Surface modification of products is also aimed at improving their functional and protective properties. This applies to surfaces for producing hydrophobic surfaces, anti-wear protection of friction pairs, corrosion protection, and others. Metal technologies and 3D printing benefit from surface technologies that improve their functionality and facilitate the operation of products. Surface engineering offers a range of different coating and layering methods from varnishing and painting to sophisticated nanometric coatings. This paper presents an overview of selected surface engineering issues pertaining to metal products, with a particular focus on surface modification of products manufactured by 3D printing technology. It evaluates the impact of the surface quality of products on their functional and performance qualities. [ABSTRACT FROM AUTHOR]

Modifying cells with polymers on the surface can enable them to gain or enhance function with various applications, wherein the atom transfer radical polymerization (ATRP) has garnered significant potential due to its biocompatibility. However, specifically initiating ATRP from the cell surface for in-situ modification remains challenging. This study established a bacterial surface-initiated ATRP method and further applied it for enhanced Cr(VI) removal. The cell surface specificity was facilely achieved by cell surface labelling with azide substrates, following alkynyl ATRP initiator specifically anchoring with azide–alkyne click chemistry. Then, the ATRP polymerization was initiated from the cell surface, and different polymers were successfully applied to in-situ modification. Further analysis revealed that the modification of Shewanella oneidensis with poly (4-vinyl pyridine) and sodium polymethacrylate improved the heavy metal tolerance and enhanced the Cr(VI) removal rate of 2.6 times from 0.088 h−1 to 0.314 h−1. This work provided a novel idea for bacterial surface modification and would extend the application of ATRP in bioremediation. [Display omitted] • ATRP specifically initiated from the bacterial cell surface was developed. • Bacterial cell was successfully modified by this new ATRP method. • The surface modified bacterial cell exhibited enhanced Cr(VI) removal. [ABSTRACT FROM AUTHOR]

Cavitation wear is causing considerable financial losses for a range of industries, such as chemical, food processing and hydropower plants. Microwave cladding process involves the application of a coating of another material over the surface of a specific material, which offers properties beneficial for high electrical conductivity, low loss tangent and excellent thermal stability. This review article is intended to provide a basic understanding of the properties of various types of microwave cladding materials. This chapter also emphasises on the characterisation of the samples produced through the microwave cladding on various substrate materials. Furthermore, this chapter describes the potential applications of the microwave cladding process in numerous engineering and industrial sectors. Additionally, this chapter also reports the potential future technological advancements in the field of microwave cladding process. [ABSTRACT FROM AUTHOR]

All‐inorganic CsPbCl3 perovskite has emerged as a promising material for ultraviolet (UV) photodetection, attributed to its appropriate bandgap and exceptional optoelectronic properties. However, the suboptimal film‐forming quality of the solution process, as well as the instability of films induced by UV radiation and the annealing process, have limited its popularization and application. Herein, the buried layer is pretreated with N, N‐dimethylacetamide (DMF) to improve surface hydrophilicity and facilitate the anchoring of Pb2+. Additionally, Nb2CTx is incorporated into the PbCl2 precursor solution to enhance the quality of CsPbCl3 films. Following surface engineering and Nb2CTx modification (CsPbCl3@Nb2CTx), the morphology and optoelectronic properties of CsPbCl3 films are optimized. Furthermore, the effect of lattice strain and defect state‐induced interface state on the nonradiative charge recombination is mitigated. Ultimately, the UV photodetector fabricated on fluorine‐doped tin oxide (FTO)/SnO2/CsPbCl3@Nb2CTx/Au architecture exhibits outstanding performance including remarkably high responsivity (up to 990 mA W−1), significant specific detectivity (1.03 × 1011 cm Hz1/2 W−1), and rapid rise/decay time (0.24/0.32 µs) under self‐powered mode, with markedly improved stability as well. This approach presents a novel strategy for optimizing CsPbCl3 films through MXene modulation as an immense potential absorb layer for UV photodetector. [ABSTRACT FROM AUTHOR]

With the increasing requirements from toxic and hazardous gas detection technologies, WO 3 -based gas sensors have garnered tremendous interest on account of their low operating temperatures, good cycling stability, and short response/recovery time. So far, considerable progress has been made in the design and preparation of different architectures of WO 3. The sensing mechanism of WO 3 -based gas sensors is relatively complex. To further optimize the capabilities of WO 3 -based gas sensors, the influencing factors of the sensing mechanism need to be deeply understood to seek more effective enhanced strategies. This review probes the application of WO 3 -based sensors for various dangerous gases and contrastively analyses the sensing behavior of WO 3 in detail. In addition, we pay special attention to the interfacial interaction pathways between the sensing material and the target gas. Nowadays, more efforts are being made to strengthen the sensing properties of WO 3 -based materials so that they can be used in more smart demanding and complex environments. The authors focus on four approaches, namely, morphology control, hybridization, defect engineering, and photoactivation, for enhancing gas sensors and providing a comprehensive study of WO 3 for gas-sensing applications. Finally, we discuss the current problems and improvement methods and provide an outlook on the development trend of WO 3 -based gas sensors. The WO 3 -based gas sensitive materials are reviewed from adsorption, reactive and transducing interfacial issues, and their sensitivity and selectivity can be improved prominently by quaternary strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights The demand for polymers with antibacterial properties is increasing in food packaging industry and medical supplies. Antibacterial additives without toxic metal ion release are crucial for health and safety but still have challenges. Herein, polypropylene (PP) nanocomposite was prepared with polyaniline/graphene nanocomposite (PANI/GNP) as a green antibacterial additive due to its electrostatic, free radical, and nanoknife effect synergistic antibacterial mechanisms. To improve the dispersibility of PANI/GNP, nanosilica coating on PANI/GNP was constructed successfully with in situ condensation polymerization of epoxy functionalized ethyl orthosilicate to obtain EP‐nSiO2‐PANI/GNP. EP‐nSiO2‐PANI/GNP with a thin nanosilica coating has a significantly improved thermal stability as compared with that of PANI/GNP characterized by TGA. The EP‐nSiO2‐PANI/GNP presents a nanoscale disperse state in PP nanocomposite and thus enhances the melt viscosity and storage modulus accordingly characterized by TEM and Rheology. The EP‐nSiO2‐PANI/GNP/PP filled with 0.5 wt% of EP‐nSiO2‐PANI/GNP demonstrates antibacterial activity of 100% against both Escherichia coli and Staphylococcus aureus. In situ condensation polymerization to prepare EP‐nSiO2‐PANI/GNP. EP‐nSiO2‐PANI/GNP has enhanced dispersion stability. EP‐nSiO2‐PANI/GNP with a thin nanosilica coating has a good thermal stability. PP nanocomposite with 0.5 wt% filler has excellent antibacterial activity. The electrostatic, free radical, and nanoknife effect antibacterial mechanism. [ABSTRACT FROM AUTHOR]

The development and characterization of bioactive surfaces based on chitosan-polyethylene glycol coatings modified with hydroxyapatite on Ti6Al4V alloy were conducted to enhance bioactivity. Characterization techniques such as scanning electron microscopy, X-ray diffraction, infrared spectroscopy, atomic absorption spectroscopy, and electrochemical impedance spectroscopy were used to evaluate coating properties, apatite formation after immersion in simulated body fluid, and electrochemical stability. Results demonstrated apatite deposition due to the bioactivity of the polymer-ceramic composite, with calcium accumulation observed on the substrate surface after 5 days of immersion. Electrochemical impedance spectroscopy revealed a highly capacitive layer in the 50:50 chitosanpolyethylene glycol coating with 0.05% w/v hydroxyapatite, indicating increased interaction with the biological medium while preserving the protective resistive properties of the Ti6Al4V alloy. These findings suggest that this coating composition is a promising material for bone tissue regeneration applications. [ABSTRACT FROM AUTHOR]

Motivated by the recent discoveries concerning the exceptional surface engineering capabilities offered by high-entropy alloys (HEAs), this article investigates the tribological behavior of pristine and graphene nano-engineered AlxCoCrFeNi HEA. The atomic-scale scratching is performed for different configurations of HEA in a molecular dynamics environment, wherein, at first, aluminum (Al) (x = 0.1, 0.3, and 0.5) concentration-dependent wear behavior of HEA configurations is compared. It is observed that with the increase in Al concentration, the normal and tangential forces, friction coefficients, and wear-rates were significantly reduced, due to the increased plastic deformation and phase transformation. Graphene-engineered HEA surfaces are perceived in two different ways, in the presented investigation: first, the graphene coating is applied directly over the HEA surface, and second, the graphene layers are embedded at a certain depth below the target surface. It is observed that graphene-engineered HEA surfaces exhibit exceptional performance against nano-scratching, wherein, the distribution and height of surface morphology (pile-ups) have seen significant improvement and elastic recovery, especially in the cases of graphene coating over the surface. The findings obtained from this study will be extremely helpful in bringing the bottom-up multi-scale design route for graphene-engineered HEA surfaces to reality. This will enable the development of a novel class of functionally engineered surfaces with enhanced wear and scratch resistance. [ABSTRACT FROM AUTHOR]

The topography analysis of engineered rough surfaces provides an insight for an analysis of thin film lubrication regime. The systematic characterization of rough surface helps to improve the lifetime performance and the reliability of high-power density (power throughput/weight) machines. Tribological phenomena like rolling contact fatigue, fretting fatigue, and wear significantly depend on characteristics of rough surfaces. This work demonstrates the numerical synthesis and characterization of various rough surfaces. Surface topographies are numerically simulated using nonlinear conjugate gradient method (NCGM) along with the Johnson translator system method. The influence of pattern ratio (γ), skewness (Ssk) and kurtosis (Sku) on topography parameters (summit density, summit radius of curvature) are discussed in detail. It is concluded that a selection of surface topography significantly alters topography parameters which ultimately may affect surface dominant phenomena. The trend on topography parameters obtained from numerical findings are also compared with the surface measurements study for the completeness of the work. [ABSTRACT FROM AUTHOR]

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Yi Xiao,1,2,* Shiyan Yang,2,3,* Yang Sun,2,* Robert L Sah,4,5 Jincheng Wang,2 Chunshan Han1 1Thoracic Surgery Department, The China-Japan Union Hospital of Jilin University, Changchun, Jilin, 130000, People’s Republic of China; 2Orthopedic Medical Center, the Second Hospital of Jilin University, Changchun, Jilin, 130000, People’s Republic of China; 3Department of Head and Neck, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong, 510060, People’s Republic of China; 4Department of Bioengineering, University of California–San Diego, La Jolla, CA, 92037, USA; 5Center for Musculoskeletal Research, Institute of Engineering in Medicine, University of California–San Diego, La Jolla, CA, 92037, USA*These authors contributed equally to this workCorrespondence: Chunshan Han, Thoracic Surgery Department, the China-Japan Union Hospital of Jilin University, Changchun, Jilin, 130000, People’s Republic of China, Email hancs@jlu.edu.cnAbstract: Nanoscale morphologies on the surface of substrates/scaffolds have gained considerable attention in cartilage tissue engineering for their potential to improve chondrogenic differentiation and cartilage regeneration outcomes by mimicking the topographical and biophysical properties of the extracellular matrix (ECM). To evaluate the influence of nanoscale surface morphologies on chondrogenic differentiation of stem cells and discuss available strategies, we systematically searched evidence according to the PRISMA guidelines on PubMed, Embase, Web of Science, and Cochrane (until April 2024) and registered on the OSF (osf.io/3kvdb). The inclusion criteria were (in vitro) studies reporting the chondrogenic differentiation outcomes of nanoscale morphologies on the surface of substrates/scaffolds. The risk of bias (RoB) was assessed using the JBI-adapted quasi-experimental study assessment tool. Out of 1530 retrieved articles, 14 studies met the inclusion criteria. The evidence suggests that nanoholes, nanogrills, nanoparticles with a diameter of 10– 40nm, nanotubes with a diameter of 70– 100nm, nanopillars with a height of 127– 330nm, and hexagonal nanostructures with a periodicity of 302– 733nm on the surface of substrates/scaffolds result in better cell adhesion, growth, and chondrogenic differentiation of stem cells compared to the smooth/unpatterned ones through increasing integrin expression. Large nanoparticles with 300– 1200nm diameter promote pre-chondrogenic cellular aggregation. The synergistic effects of the surface nanoscale topography and other environmental physical characteristics, such as matrix stiffness, also play important in the chondrogenic differentiation of stem cells. The RoB was low in 86% (12/14) of studies and high in 14% (2/14). Our study demonstrates that nanomorphologies with specific controlled properties engineered on the surface of substrates/scaffolds enhance stem cells’ chondrogenic differentiation, which may benefit cartilage regeneration. However, given the variability in experimental designs and lack of reporting across studies, the results should be interpreted with caution.Keywords: nanomorphology, surface engineering, chondrogenesis, stem cell, cartilage regeneration

[Display omitted] • Dual-layers surface engineering of metal–organic frameworks (MOFs) nanoparticles incorporating lipid coating is presented for miRNA efficient delivery, circumventing the pore size limitation of MOFs pore encapsulation. • This layer-by-layer nanostructure sandwiched the miRNA between the MOFs core and lipid surface layer, enhancing stability of miRNA against biodegradation, but also rendering itself with improved colloidal stability, cellular uptake and lysosomal escape. • A versatile approach combines the MOF-based photodynamic therapy, miRNA gene therapy and pre-encapsulated doxorubicin chemotherapy, which synergistically works against cancer cells. MicroRNAs (miRNAs) are small noncoding RNAs that are critical for the regulation of multiple physiological and pathological processes, thus holding great clinical potential. However, the therapeutic applications of miRNAs are severely limited by their biological instability and poor intracellular delivery. Herein, we describe a dual-layers surface engineering strategy to design an efficient miRNA delivery nanosystem based on metal–organic frameworks (MOFs) incorporating lipid coating. The resulting nanoparticle system was demonstrated to protect miRNA from ribonuclease degradation, enhance cellular uptake and facilitate lysosomal escape. These ensured effective miRNA mediated gene therapy, which synergized with MOF-specific photodynamic therapy and pre-encapsulated doxorubicin (Dox) chemotherapy to provide a multifunctional with therapeutic effectiveness against cencer cells The mechanisms of miRNA binding and Dox loading were revealed, demonstrating the potential of the present MOFs surface-engineered strategy to overcome their inherent pore-size restriction for macromolecular miRNA carrying, enableefficient co-delivery. In vitro studies revealed the potential of our multifunctional system for miRNA delivery and the demonstrated the therapeutic effectiveness against cancer cells, thereby providing a versatile all-in-one MOFs strategy for delivery of nucleic acids and diverse therapeutic molecules in synergistic therapy. [ABSTRACT FROM AUTHOR]

The S-doped PtMn concave cubes enclosed with high index facet and regulatable surface strain are successfully fabricated by two steps hydrothermal method. The PtMnS 1.1 catalyst exhibits superior catalytic properties for ethanol electrooxidation reaction in acidic and alkaline media, which is ascribed to the optimal surface strain and unsaturated surface-active sites. [Display omitted] Surface strain engineering has proven to be an efficient strategy to enhance catalytic properties of platinum (Pt)-based catalysts for electrooxidation reactions. Herein, the S-doped PtMn concave cubes (CNCs) enclosed with high index facets (HIFs) and regulatable surface strain are successfully fabricated by two steps hydrothermal method. The S element with electrophilic property can modify the near-surface of PtMn nanocrystals, altering the electronic structure of Pt to effectively regulate the adsorption/desorption of intermediates in the ethanol electrooxidation reaction (EOR). The PtMnS 1.1 catalyst with optimal surface strain delivered extraordinary catalytic performance on EOR in acidic media, with a specific activity of 2.88 mA/cm2 and mass activity of 1.10 mA/μg Pt , which is 4.1 and 2.2 times larger than that of state-of-the-art Pt/C catalyst, respectively. Additionally, the PtMnS 1.1 catalyst also achieve excellent catalytic properties in alkaline electrolyte for EOR. The results of kinetic studies indicated that the surface strain and modified electronic structure can degrade the activation energy barrier during the process of EOR, which is beneficial for enhance the reaction rate. This work provides a promising approach to construct highly efficient electrocatalysts with tunable surface strain effects for clean energy electro-chemical reactions. [ABSTRACT FROM AUTHOR]

Mengjie Xie,1,* Fansu Meng,2,* Panpan Wang,3,* Alicia Marcelina Díaz-García,4 Marina Parkhats,5 Ralph Santos-Oliveira,6 Mulazim Hussain Asim,7 Nazish Bostan,8 Honghui Gu,9 Lina Yang,9 Qi Li,9 Zhenjiang Yang,9 Haibiao Lai,2 Yu Cai1 1State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education (MOE) of China / Guangdong Key Laboratory of Traditional Chinese Medicine Informatization / International Science and Technology Cooperation Base of Guangdong Province/School of Pharmacy, Jinan University, Guangzhou, Guangdong, 510632, People’s Republic of China; 2Zhongshan Hospital of Traditional Chinese Medicine Affiliated to Guangzhou University of Traditional Chinese Medicine, Zhongshan, Guangdong, 528400, People’s Republic of China; 3The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, 510632, People’s Republic of China; 4Bioinorganic Laboratory, Faculty of Chemistry, University of Havana, Havana, 1400, Cuba; 5B. I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk, 220072, Belarus; 6Brazilian Nuclear Energy Commission, Nuclear Engineering Institute, Laboratory of Nanoradiopharmacy and Synthesis of New Radiopharmaceuticals, Rio de Janeiro, RJ, 21941906, Brazil; 7College of Pharmacy, University of Sargodha, Punjab, 40100, Pakistan; 8Department of Pharmaceutics, Faculty of Pharmacy, The Islamia University of Bahawalpur, Bahawalpur, 63100, Pakistan; 9Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, Guangdong, 518033, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yu Cai; Haibiao Lai, Email caiyu8@sohu.com; lhb8829@163.comAbstract: Data published in 2020 by the International Agency for Research on Cancer (IARC) of the World Health Organization show that breast cancer (BC) has become the most common cancer globally, affecting more than 2 million women each year. The complex tumor microenvironment, drug resistance, metastasis, and poor prognosis constitute the primary challenges in the current diagnosis and treatment of BC. Magnetic iron oxide nanoparticles (MIONPs) have emerged as a promising nanoplatform for diagnostic tumor imaging as well as therapeutic drug-targeted delivery due to their unique physicochemical properties. The extensive surface engineering has given rise to multifunctionalized MIONPs. In this review, the latest advancements in surface modification strategies of MIONPs over the past five years are summarized and categorized as constrast agents and drug delivery platforms. Additionally, the remaining challenges and future prospects of MIONPs-based targeted delivery are discussed. Keywords: Nanopreparations, Organic Nanomaterials, Inorganic Nanomaterials, Surface Engineering, Targeted Delivery

The paper presents the results of research on the surface topography and electrical properties of ITO thin films deposited by PVD for applications in silicon photovoltaic cells. The surface condition and chemical composition were characterized using a scanning electron microscope and the thickness and optical constants were measured using a spectroscopic ellipsometer. To compare the impact of the preparation process on the properties of layers, deposition was carried out at three different temperatures: 25, 200, and 400°C. As the temperature increased, the surface roughness changed, which correlated with the results of structural tests. The crystallite size increased from 11 to 46 nm. This, in turn, reduced the surface resistance. The electrical properties were measured using a four-point probe method and then the prepared solar cells containing ITO thin films in their structure were examined. By controlling the deposition parameters, the surface resistance of the deposited layer (26 Ohm/2) and the efficiency of the prepared solar cells (18.91%) were optimized. Currently, ITO has the best properties for use in optoelectronics and photovoltaics among the known TCO layers. The magnetron sputtering method is widely used in many industries. Therefore, the authors predict that TCO layers can replace currently used antireflection layers and reduce the number and dimensions of front metal contacts in solar cells. [ABSTRACT FROM AUTHOR]

Surface engineering techniques can be used to develop high-performance gas sensing materials and advance the development of sensors. In this study, we improved the gas sensing performance of two-dimensional (2D) WO3 nanoplates by combining surface Zn modification and the in situ formation of ZnWO4/WO3 heterojunctions. Introducing Zn atoms by surface modification can reconstruct the atomic surface of 2D WO3 nanoplates, creating additional active sites. This allowed for the preparation of various types of ZnWO4/WO3 heterojunctions on the surface of the WO3 nanoplates, which improved the selectivity and sensitivity to the target gas triethylamine. The sensor exhibited good gas sensing performance for triethylamine even at low operating temperatures and strongly resisted humidity changes. The ZnWO4/WO3 material we prepared demonstrated a nearly threefold improvement in the triethylamine (TEA) response, with a gas sensing responsivity of 40.75 for 10 ppm of TEA at 250 °C. The sensor based on ZnWO4/WO3 has a limit of detection (LOD) for TEA of 200 ppb in practical measurements (its theoretical LOD is even as low as 31 ppb). The method of growing ZnWO4 on the surface of WO3 nanoplates using surface modification techniques to form surface heterojunctions differs from ordinary composites. The results suggest that the in situ construction of surface heterojunctions using surface engineering strategies, such as in situ modifying, is a practical approach to enhance the gas sensing properties and resistance to the humidity changes of metal oxide materials. [ABSTRACT FROM AUTHOR]

The results of the influence of a range of process liquids on the formation of strengthened nanocrystalline structures in the surface layers of steel samples with different carbon content during thermo-deformation treatment are presented. The liquids were mineral oil; mineral oil with active additives containing polymers; water; and an aqueous solution of mineral salts based on magnesium and calcium chlorides. The thickness and hardness of the nanocrystalline layer increased with increasing steel carbon content. The thickness and microhardness of Steel C45 are 230–240 μm and 8.6 GPa, respectively, when using mineral oil with AAP, 110–120 μm and 7.2 GPa, respectively, when using mineral oil alone, and for steel CT80 when using mineral oil, they are 180–200 μm and 9.1 GPa, respectively (C45 and CT80 refers to engineering steels). The process liquid is decomposed into its component chemical elements by the high temperatures and pressures in the contact zone of the tool with the treated surface. It also gives off active hydrogen, which diffuses into the surface layer of the metal and significantly affects its formation. It was established that the greatest thickness and hardness of the layers were obtained after processing pre-hydrogenated samples. The choice of process fluid is critical during thermo-deformation treatment. [ABSTRACT FROM AUTHOR]

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Polystyrene (PS) is a very common material in packaging. In this study, it is recycled by turning it into energy harvesting devices: triboelectric generators. Herein, heat‐pressed films of recycled PS are formed and their surfaces are modified physically and chemically. The triboelectric properties of the films are determined using a dynamic testing machine, and the performance of the triboelectric generators is evaluated with a high‐speed contact–separation system. The developed charge density of the triboelectric generator increases two orders of magnitude—from 0.03 to 1.52 nC cm−2—by combining these surface modification methods. Such high values of charge density enable the production of single material triboelectric generators. [ABSTRACT FROM AUTHOR]

Stainless steel surfaces can be modified using plasma‐assisted thermochemical treatments to improve properties like hardness, wear, and pitting corrosion resistance. To specifically adjust the desired properties, a precise control of the produced treatment‐relevant gas species with regard to their type and concentration is essential. This requires the adjustment of the parameters for the generation of the gas species, being independent from heating parameters, as well as their real‐time measurement. Therefore, this study presents the use of a plasma‐activated solid carbon precursor in a cold‐wall reactor using active screen technology and in a modified hot‐wall reactor during plasma nitrocarburizing of austenitic stainless steel. In addition, the modified hot‐wall reactor combined with a compact laser‐based absorption spectroscopy sensor for real‐time monitoring and concentration evaluation of in‐site generated gas species. It is shown that implementing a plasma‐activated solid carbon precursor in a modified hot‐wall reactor enables adjustable generation of C‐containing gas species, particularly HCN, with high production yield by an independent power management. Therefore, HCN is produced independent from heating while the limitations arising during active screen technology using a carbon screen are avoided. The presented technological development thus opens up new possibilities for better control of the plasma nitrocarburizing treatments of steels. [ABSTRACT FROM AUTHOR]

This study aimed to comprehensively assess the influence of the nanotube diameter and the presence of a silicon carbide (SiC) coating on microbial proliferation on nanostructured titanium surfaces. An experiment used 72 anodized titanium sheets with varying nanotube diameters of 50 and 100 nm. These sheets were divided into four groups: non-coated 50 nm titanium nanotubes, SiC-coated 50 nm titanium nanotubes, non-coated 100 nm titanium nanotubes, and SiC-coated 100 nm titanium nanotubes, totaling 36 samples per group. P. gingivalis and T. denticola reference strains were used to evaluate microbial proliferation. Samples were assessed over 3 and 7 days using fluorescence microscopy with a live/dead viability kit and scanning electron microscopy (SEM). At the 3-day time point, fluorescence and SEM images revealed a lower density of microorganisms in the 50 nm samples than in the 100 nm samples. However, there was a consistently low density of T. denticola across all the groups. Fluorescence images indicated that most bacteria were viable at this time. By the 7th day, there was a decrease in the microorganism density, except for T. denticola in the non-coated samples. Additionally, more dead bacteria were detected at this later time point. These findings suggest that the titanium nanotube diameter and the presence of the SiC coating influenced bacterial proliferation. The results hinted at a potential antibacterial effect on the 50 nm diameter and the coated surfaces. These insights contribute valuable knowledge to dental implantology, paving the way for developing innovative strategies to enhance the antimicrobial properties of dental implant materials and mitigate peri-implant infections. [ABSTRACT FROM AUTHOR]

Surface side reactions and time‐consuming modification methods hinder the practical application of zinc‐ion batteries. This study introduces an ultrathin protection layer for the Zn anode via a rapid sputtering method. The dopants on the CN10@Zn anode create surface dipoles and local variations in charge distribution, facilitating zinc ion migration to pyrrolic nitrogen dopant sites with reduced adsorption barriers. Additionally, hydroxyl oxygen dopants enhance the hydrophilicity of the sputtering layer, forming a strong adhesion with the zinc anode and improving ion accessibility. This results in dense nucleation sites for uniform zinc deposition. Consequently, the sputtered layer achieves a Coulombic efficiency of 99.8% over 2,700 cycles in Cu||Zn cells and a lifespan of up to 2,100 h in zinc symmetric cells. When paired with Na0.65Mn2O4 cathodes, the sputtered layer retains 89% capacity over 1,000 cycles at 1 A g−1. This study presents a promising method for rapidly fabricating ultrathin electrode materials. [ABSTRACT FROM AUTHOR]

This report introduces a novel method for fabricating electrocatalysts, where hematite (α-Fe2O3) is interface-functionalized with organic ligands to enhance the oxygen evolution reaction (OER). The synthesized samples feature nanoparticle morphology and crystalline structures consistent with hematite, known for its high stability among iron oxides. Functional groups from benzimidazole (bIm) and caffeine (Caf) act as scaffolds and sources of carbon, hydrogen, oxygen, and nitrogen, promoting metal-support interactions (MSIs) to boost OER activity and aid the formation of hematite nanocrystals. The optimal catalyst, Fe-(bIm)-0.3Caf, is synthesized using a mix of ligands, mainly bIm with 30% Caf substitution. This combination introduces defects in the hematite structure, creating additional active sites and oxygen vacancies, which significantly improve OER performance. Fe-(bIm)-0.3Caf exhibits the lowest overpotential (264 mV at 10 mA cm-2) and the smallest Tafel slope (30 mV dec-1) among all prepared samples and commercial Fe2O3. In contrast, commercial Fe2O3 shows higher overpotential (331 mV at 10 mA cm-2) and lower durability under identical conditions in 1 M KOH over 30 h at room temperature. These findings underscore the importance of surface engineering of hematite nanocrystals to modify the surface and electronic structure, enhancing OER efficiency. This report also outlines a streamlined one-pot hydrothermal process for preparing interface-functionalized hematite nanocrystals at low temperatures, highlighting a promising approach for achieving efficient and durable electrocatalyst performance in driving the OER. The study emphasizes the crucial role of mixed ligands in enhancing OER efficiency in alkaline media. [ABSTRACT FROM AUTHOR]

Dynamic molecular crystals are an emerging class of crystalline materials that can respond to mechanical stress by dissipating internal strain in a number of ways. Given the serendipitous nature of the discovery of such crystals, progress in the field requires advances in computational methods for the accurate and high–throughput computation of the nanomechanical properties of crystals on specific facets which are exposed to mechanical stress. Here, we develop and apply a new atomistic model for computing the surface elastic moduli of crystals on any set of facets of interest using dispersion–corrected density functional theory (DFT−D) methods. The model was benchmarked against a total of 24 reported nanoindentation measurements from a diverse set of molecular crystals and was found to be generally reliable. Using only the experimental crystal structure of the dietary supplement, L–aspartic acid, the model was subsequently applied under blind test conditions, to correctly predict the growth morphology, facet and nanomechanical properties of L–aspartic acid to within the accuracy of the measured elastic stiffness of the crystal, 24.53±0.56 GPa. This work paves the way for the computational design and experimental realization of other functional molecular crystals with tailor–made mechanical properties. [ABSTRACT FROM AUTHOR]

Chemical vapor deposition (CVD) is a vital process for deposit of thin films of various materials with precise control over the thickness, composition, and properties. Understanding the mechanisms of heat and mass transfer during CVD is essential for optimizing process parameters and ensuring high-quality film deposition. This review provides an overview of recent advancements in heat and mass transfer modeling for chemical vapor deposition processes. It explores innovative modeling techniques, recent research findings, emerging applications, and challenges in the field. Additionally, it discusses future directions and potential areas for further advancement in CVD modeling. [ABSTRACT FROM AUTHOR]

Surface finish and morphology play a vital role in the reliability and life of cam-roller or slider mechanisms, with improvement due to lesser contact pressure-based fatigue and failure as surface finish improves. An experimental setup using magnet-based abrasive finishing techniques is designed and developed to conduct studies on a double camshaft follower arrangement that resulted in less than 300 nm finish at an enhanced finishing rate. Finishing rate improves greatly as speed of rotation of the workpiece increases with relatively bigger abrasive particles while the best finish is obtained at lower speeds and particle sizes with progression of the finishing cycles. Subsequently, using the results as the training dataset, a machine learning system is developed to overcome the limitations of surface measurement techniques and human interventions, to predict outcomes like number of cycles, speed of rotation of workpiece, time to reach the desired finish and particle size to be used for the given material of workpiece, initial surface roughness and final desired surface finish. The predictions from the completely trained system are compared with the physics-based model and the real data and the error is found to be within 20 nm which has led to development of a highly reliable system. [Display omitted] [ABSTRACT FROM AUTHOR]

This work studies the mechanical behavior of microalloyed steels (API X60 and API X70) with boride layers using a boriding process and immersion in diesel. First, the microalloyed steels were borided using dehydrated boron paste at a temperature of 1273 K for 6 h, and then the borided microalloyed steels were immersed in diesel for one year. The characterization of the layers on the specimens subjected to diesel used scanning electron microscopy (SEM), energy dispersive spectroscopy, and X-ray diffraction (XRD). The evaluation of the mechanical properties was performed with tensile tests according to ASTM E8, and then the fracture surface was observed by SEM. This work contributes to the understanding of the changes in the mechanical properties of borided microalloyed steel immersed in diesel for possible potential applications in the storage of fuels, oils, hydrogen, and biofuels. [ABSTRACT FROM AUTHOR]

Thermomechanical fatigue of refractory metals is commonly observed in high-temperature environments like first walls and divertors for proposed fusion reactors or X-ray anodes for medical imaging. Typically, alloying with rhenium or optimized microstructures are employed to counteract or delay the detrimental effects of fatigue in tungsten. Additionally, a novel concept is the utilization of surface structures to compensate cyclic thermal stresses. This work aimed to investigate the combination of these approaches, by comparing two W10Re alloys with vastly different microstructures, as well as engineered surface conditions of varying scales. Samples were subjected to thermocyclic fatigue under pulsed electron beam exposure, mimicking the surface temperatures typically encountered in a rotating X-ray anode. Analysis of several in-situ data streams, post-mortem investigations by metallography, and finite element methods revealed the interplay between microstructure and surface modifications. The columnar microstructure exhibited higher resistance to severe surface damage compared to the globular one, linked to the deflection of cracks along grain boundaries and subsequent melting. Coarse structuring was found to partly relieve the surface stresses during thermal cycling, preventing most of the damage accumulation. A full damage relief and performance equivalence between columnar and globular microstructure was achieved by engineering fine-structured surfaces, which led to a ten-fold increase in fatigue resistance over the non-structured condition.

Abstract Crystallization fouling, a process where mineral scales form on surfaces, is of broad importance in nature and technology, negatively impacting water treatment and electricity production. However, a rational methodology for designing materials with intrinsic resistance to scaling and scale adhesion remains elusive. Here, guided by nucleation physics, this work investigates the effect of coating composition and surface structure on the nucleation and growth mechanism of scale on metallic heat transfer surfaces nanoengineered by large‐area techniques. This work observes that on hydrophilic nanostructured copper, despite its significantly enlarged surface area compared to smooth surfaces, scale formation is substantially suppressed leading to sustained, efficient cooling performance. This work reveals the mechanism through thermofluidic modeling coupled with in situ optical characterization and show that surface bubble formation through degassing is responsible for generating local hot spots enhancing supersaturation. This work then demonstrates a scalephobic nanostructured surface which reduces the accumulated surface scale mass 3.5× and maintains an 82% higher heat transfer coefficient compared to superhydrophobic surfaces with corresponding energy conversion savings. This work not only advances the understanding of fouling mechanisms but also holds promise for practical applications in industries reliant on efficient heat transfer processes.

The 2A12 aluminum alloy, renowned for its exceptional mechanical properties, encounters significant limitations in applications involving abrasive environments or frequent contact with other surfaces due to its inadequate wear resistance. This shortcoming substantially reduces the service life of components and escalate maintenance costs, highlighting the urgent need for advanced surface modification techniques. This study meticulously investigates the influence of nanoceramic particle size and content on the wear resistance of micro-arc oxidation (MAO) coatings, a surface modification technique renowned for forming dense, adherent ceramic layers on aluminum alloys. The systematic experimentation revealed that the incorporation of 150 nm α-Al2O3 nanoparticles into the MAO matrix achieves an optimal dispersion, leading to a substantial enhancement in wear resistance. The sample with a 5 g/L concentration of 150 nm α-Al2O3 nanoparticles doping in the MAO electrolyte demonstrated the lowest mass loss, underscoring its enhanced wear resistance. The enhanced microstructure, enriched with hard ceramic phases such as α-Al2O3 and mullite, plays a pivotal role in withstanding wear. Moreover, this study identified that an optimal balance of surface roughness and coating thickness is essential for achieving enhanced wear resistance. The findings of this research provide a strategy for the design of wear-resistant coatings tailored for high-performance applications across aerospace, automotive, and general engineering industries. By optimizing the particle size and concentration in MAO coatings, this study paves the way for the development of durable materials capable of thriving in demanding environments, thereby extending the service life and reducing maintenance requirements of components.

Surface functionality plays a pivotal role in Tribology, a discipline dedicated to examining the interactions of surfaces in relative motion. The approach, known as Tribotronics, combines Tribology and electronics, enabling active tribological components to be embedded in larger systems and networks constituting the Industrial Internet of Things. Leveraging novel technologies such as advanced sensing coatings and triboelectric nanogenerators, the sensing capability of Tribotronic systems undergoes a transformative shift from a device‐centric to a surface‐centric paradigm. This critical advancement unlocks the potential for direct interface probing and in‐situ measurement of tribological processes, marking a significant milestone in the field. This emerging trend introduces the concept of the Internet of Surfaces, a novel perspective within surface engineering. It entails the amalgamation of sensing capabilities, embedded power generation, and external analytics, creating dynamic materials in the context of Industry 4.0. [ABSTRACT FROM AUTHOR]