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The generation of hydrophobic surfaces through laser ablation has garnered considerable attention, particularly for its prospective diverse applications across various industries. This study explores the possibility of generating controllable hydrophobic metasurfaces on Ni-Mn-Ga-based magnetic shape memory (MSM) alloys using femtosecond pulse width laser (FPWL). While hydrophobic surfaces have been achieved on different materials through a variety of different techniques, the research marks the first systematic attempt to tailor hydrophobicity on the surface of Ni-Mn-Ga-based alloys. By characterizing surfaces treated with different laser parameters, the distinct morphologies and hydrophobic properties corresponding to each surface were identified. This newfound control over surface properties with specific machining parameters opens possibilities for applications in microfluidic devices. Additionally, the potential of utilizing the magnetic-field-induced strain (MFIS) exhibited by Ni-Mn-Ga single crystals to alter surface hydrophobicity was explored. Metasurfaces mimicking the dimensional changes in elongation induced by MFIS demonstrated higher static contact angles (SCAs) for water droplets compared to the original surfaces. This approach presents a promising avenue for creating multifunctional microdevices with controllable hydrophobicity using Ni-Mn-Ga-based alloys. Our findings not only offer insights into tailoring of hydrophobic/hydrophilic properties on Ni-Mn-Ga-based MSM alloys but also provide a novel methodology for fabricating functional metasurfaces on other metals.

Abstract This study presents a technique for processing transparent glass and resin substrates using a low-cost laser marker to create a micro-nano-structured surface with exceptional anti-fog properties. The approach involved depositing an aluminum (Al) film on the transparent substrates as an absorbing layer, followed by rapid laser marker ablation. This ablation process effectively removed the majority of the Al film, resulting in the formation of hierarchical hillock-hollow micro-structures and the dispersion of Al-based nano-particles throughout the surface. The resulting structure on resin glasses demonstrated anti-fog performance even after 629 days storage in the laboratory, which marked the longest antifog record. It exhibited impressive antifog property without visible degradation for the first 9 months, which though degraded substantially afterwards. Furthermore, the micro-nano structure played a key role in reducing the contact angle of the surface. The contact angle experienced a significant reduction from a value of 64° for the control resin to 6.9° for the treated resin, while it was reduced from 44° for the control glass to 0° for the treated glass, indicating superhydrophilicity. This 0° superhydrophilic state persisted for a period of 25 days.

This study presents a technique for processing transparent glass and resin substrates using a low-cost laser marker to create a micro-nano-structured surface with exceptional anti-fog properties. The approach involved depositing an aluminum (Al) film on the transparent substrates as an absorbing layer, followed by rapid laser marker ablation. This ablation process effectively removed the majority of the Al film, resulting in the formation of hierarchical hillock-hollow micro-structures and the dispersion of Al-based nano-particles throughout the surface. The resulting structure on resin glasses demonstrated anti-fog performance even after 629 days storage in the laboratory, which marked the longest antifog record. It exhibited impressive antifog property without visible degradation for the first 9 months, which though degraded substantially afterwards. Furthermore, the micro-nano structure played a key role in reducing the contact angle of the surface. The contact angle experienced a significant reduction from a value of 64° for the control resin to 6.9° for the treated resin, while it was reduced from 44° for the control glass to 0° for the treated glass, indicating superhydrophilicity. This 0° superhydrophilic state persisted for a period of 25 days. [ABSTRACT FROM AUTHOR]

Metal oxide semiconductors (MOSs) hold great promise for electronic devices such as gas sensors. The utilization of ZnO as a conductometric gas sensor material can be traced back to its early stages; however, its application has primarily been limited to high-temperature environments. A gas sensor based on highly porous and interconnected 3D networks of ZnO tetrapod (ZnO-T) micro-nano structures was fabricated via an easy chemical vapor deposition (CVD) method. Homemade instruments were utilized to evaluate the gas-sensing of the sample at room temperature. It exhibited good gas-sensing at room temperature, particularly with a response of up to 338.80% toward 1600 ppm ethanol, while also demonstrating remarkable repeatability, stability, and selectivity. Moreover, the unique gas-sensing properties of ZnO-T at room temperature can be reasonably explained by considering the effect of van der Waals forces in physical adsorption and the synergistic effect of carrier concentration and mobility. The aforementioned statement presents an opportunity for the advancement of gas sensors utilizing ZnO at room temperature. [ABSTRACT FROM AUTHOR]

Improving the biomineralization of the ZrO2 ceramics surface is of great significance for field of dentistry. A femtosecond laser is used to prepare micro–nano structures on the surface of the ZrO2 ceramics. The contact angle, micromorphology, and chemical composition of the material surface are characterized using a contact angle measurement instrument, scanning electron microscope, and energy‐dispersive spectroscopy. The changes of surface wettability of different samples areanalyzed, and the biomineralization of different micropit surfaces is evaluated through hydroxyapatite (HA) deposition experiments. The results show that the deposition effect of the femtosecond laser‐textured surface is better than that of the original surface. Femtosecond laser processing improves the surface of the material, providing additional nucleation sites for HA, which is conducive to its growth and improvement of deposition efficiency. HA deposited on hydrophobic surfaces consists of a small amount of rod‐shaped and spherical particles. While the deposition effect on hydrophilic surfaces is significantly improved, the deposited particles on hydrophilic surfaces are rod‐shaped and stacked into spherical shapes, growing into pieces after combining, and the particle number increases, the density increases, and they completely cover the textured surface. This study provides a theoretical reference and experimental basis for improving its biomineralization. [ABSTRACT FROM AUTHOR]

Researches on superhydrophobicity have been overwhelming and have shown great advantages in various fields. However, the abrasion resistance of superhydrophobic structures was usually poor, and they were easily damaged by external force or harsh environment, which greatly limited the applications of superhydrophobic surfaces. Much attention has been paid to improving the abrasion resistance of superhydrophobic materials by researchers. In this review, aimed at the advances on improving the abrasion resistance of superhydrophobic surfaces, it was summarized and compared three enhancement strategies including the reasonably design of micro‐nano structures, the adoption of adhesives, and the preparation of self‐healing surface. Finally, the applications of typical superhydrophobic materials with abrasion resistance were reviewed in various fields. In order to broaden the application fields of superhydrophobic materials, the abarasion resistance should be further improved. Therefore, we proposed the ideas for the future development of superhydrophobic materials with higher abrasion resistance. We hope that this review will provide a new approach to the preparation and development of stable superhydrophobic surfaces with higher abrasion resistance. [ABSTRACT FROM AUTHOR]

As research on superhydrophobic materials inspired by the self-cleaning and water-repellent properties of plants and animals in nature continues, the superhydrophobic preparation methods and the applications of superhydrophobic surfaces are widely reported. Silicones are preferred for the preparation of superhydrophobic materials because of their inherent hydrophobicity and strong processing ability. In the preparation of superhydrophobic materials, silicones can both form micro-/nano-structures with dehydration condensation and reduce the surface energy of the material surface because of their intrinsic hydrophobicity. The superhydrophobic layers of silicone substrates are characterized by simple and fast reactions, high-temperature resistance, UV resistance, and anti-aging. Although silicone superhydrophobic materials have the disadvantages of relatively low mechanical stability, this can be improved by the rational design of the material structure. Herein, we summarize the superhydrophobic surfaces made from silicone substrates, including the cross-linking processes of silicones through dehydration condensation and hydrosilation, and the surface hydrophobic modification by grafting hydrophobic silicones. The applications of silicone-based superhydrophobic surfaces have been introduced such as self-cleaning, corrosion resistance, oil–water separation, etc. This review article should provide an overview to the bioinspired superhydrophobic surfaces of silicone-based materials, and serve as inspiration for the development of polymer interfaces and colloid science. [ABSTRACT FROM AUTHOR]

Metal oxide semiconductors (MOSs) hold great promise for electronic devices such as gas sensors. The utilization of ZnO as a conductometric gas sensor material can be traced back to its early stages; however, its application has primarily been limited to high-temperature environments. A gas sensor based on highly porous and interconnected 3D networks of ZnO tetrapod (ZnO-T) micro-nano structures was fabricated via an easy chemical vapor deposition (CVD) method. Homemade instruments were utilized to evaluate the gas-sensing of the sample at room temperature. It exhibited good gas-sensing at room temperature, particularly with a response of up to 338.80% toward 1600 ppm ethanol, while also demonstrating remarkable repeatability, stability, and selectivity. Moreover, the unique gas-sensing properties of ZnO-T at room temperature can be reasonably explained by considering the effect of van der Waals forces in physical adsorption and the synergistic effect of carrier concentration and mobility. The aforementioned statement presents an opportunity for the advancement of gas sensors utilizing ZnO at room temperature.

Abstract Medical devices are a major component of precision medicine and play a key role in medical treatment, particularly with the rapid development of minimally invasive surgery and wearable devices. Their tissue contact properties strongly affect device performance and patient health (e.g., heat coagulation and slipperiness on surgical graspers). However, the design and optimization of these device surfaces are still indistinct and have no supporting principles. Under such conditions, natural surfaces with various unique functions can provide solutions. This review summarizes the current progress in natural functional surfaces for medical devices, including ultra-slipperiness and strong wet attachment. The underlying mechanisms of these surfaces are attributed to their coupling effects and featured micro-nano structures. Depending on various medical requirements, adaptable designs and fabrication methods have been developed. Additionally, various medical device surfaces have been validated to achieve enhanced contact properties. Based on these studies, a more promising future for medical devices can be achieved for enhanced precision medicine and human health.

Biodegradable three-dimensional porous scaffolds have attracted increasing attention as promising implants in bone tissue engineering. The micro/nano surface structure of scaffolds has also attracted significant attention due to its significant effects on scaffold physicochemical properties and cell behavior. Herein, polycaprolactone-polylactic acid-nano hydroxyapatite (PCL-PLA-nHA) ternary composite porous scaffolds with micro-nano bioactive surfaces were fabricated by combining selective laser sintering (SLS) and in situ hydrothermal deposition processes. The mechanical properties, micro/nano surface morphology, wettability, and cytocompatibility of the composite scaffolds were systematically evaluated. The results showed that the blending of PLA enhanced the compressive and tensile strength of the PCL scaffold, while also enhancing the modulus, but did not significantly change the tensile elongation. Moreover, the blending of PLA changed the fracture mode of the scaffold from ductile to brittle and its fracture mechanism was proposed. In addition, the formation mechanism of micro-nano surfaces under hydrothermal conditions was also summarized according to the micro-morphology of scaffolds. Besides, the PCL-PLA-nHA scaffold exhibited higher mineralization ability, excellent wettability, and better cytocompatibility, indicating its remarkable promise in bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

Molecular self‐assembly into hollow microstructures has great potential in catalysis, drug delivery, sensors, and nanoreactors. In contrast to well‐studied fluorescent hollow microstructures, the assembly of phosphorescent hollow microstructures has not yet been fully demonstrated. Here, two types of hollow microstructures based on organic room temperature phosphorescence (RTP) materials are prepared through a convenient vapor‐phase growth method. The observation of the assembly process and the calculations of surface energy reveal that thermodynamically driven Ostwald ripening process plays an essential role in the formation of tunable hollow structures. The universality of this growth technique for hollow microstructures is further demonstrated in various materials and even composites. Compared with non‐hollow structures, the phosphorescent hollow microstructures exhibit high sensitivity to oxygen, indicating the potential of organic hollow microstructure with RTP. [ABSTRACT FROM AUTHOR]

[Display omitted] • The possibility of generating hydrophobic surfaces on Ni-Mn-Ga-based alloys is studied for the first time. • Micro- and nanostructures generated with varied laser parameters are characterized. • A novel multi-stage process to generate hydrophobic surfaces has been introduced. • The potential for generating metasurfaces with controllable hydrophobicity using the shape memory function is explored. • These findings are crucial for developing multifunctional devices in fields like microfluidics for drop manipulation. The generation of hydrophobic surfaces through laser ablation has garnered considerable attention, particularly for its prospective diverse applications across various industries. This study explores the possibility of generating controllable hydrophobic metasurfaces on Ni-Mn-Ga-based magnetic shape memory (MSM) alloys using femtosecond pulse width laser (FPWL). While hydrophobic surfaces have been achieved on different materials through a variety of different techniques, the research marks the first systematic attempt to tailor hydrophobicity on the surface of Ni-Mn-Ga-based alloys. By characterizing surfaces treated with different laser parameters, the distinct morphologies and hydrophobic properties corresponding to each surface were identified. This newfound control over surface properties with specific machining parameters opens possibilities for applications in microfluidic devices. Additionally, the potential of utilizing the magnetic-field-induced strain (MFIS) exhibited by Ni-Mn-Ga single crystals to alter surface hydrophobicity was explored. Metasurfaces mimicking the dimensional changes in elongation induced by MFIS demonstrated higher static contact angles (SCAs) for water droplets compared to the original surfaces. This approach presents a promising avenue for creating multifunctional microdevices with controllable hydrophobicity using Ni-Mn-Ga-based alloys. Our findings not only offer insights into tailoring of hydrophobic/hydrophilic properties on Ni-Mn-Ga-based MSM alloys but also provide a novel methodology for fabricating functional metasurfaces on other metals. [ABSTRACT FROM AUTHOR]

The development of new materials for resource and energy recycling has emerged as a primary focus in addressing global energy and environmental sustainability challenges. Inspired by traditional Chinese architecture, a smart roof tile (SRT) is scientifically designed, which incorporates hierarchical micro-nanostructured polyethylene/silica/barium sulfate composites (IH-PSB), semiconductor power generation modules, and LED chips. Leveraging the combined effects of surface and interface functionalities, the IH-PSB demonstrates exceptional sub-ambient cooling capabilities, resulting in its surface and bottom temperature being 5.4 °C and 12.1 °C lower than the ambient temperature, respectively. Additionally, the precisely controlled heterogeneous wettability, with a contact angle of approximately 151° and a roll-off angle of around 32°, allows the IH-PSB to efficiently condense moisture and transport droplets. Benefiting from the excellent radiation cooling performance and precisely controlled heterogeneous wettability, the IH-PSB exhibits remarkable passive sub-dewpoint cooling efficiency coupled with efficient water harvesting performance. During a one-month outdoor experiment, the IH-PSB operated stably and continuously without any electrical input, maintaining a mass flux ranging from ∼23.2–50.0 g m−2 h−1. Interestingly, the SRT system efficiently harnesses waste heat generated by the LEDs while simultaneously regulating their temperature effectively. The development and utilization of the SRT offer a sustainable, energy-efficient, and forward-thinking solution that addresses global water scarcity and energy crises. [Display omitted] • A hierarchical micro-nanostructuredIH-PSB is designed with radiation cooling performance and heterogeneous wettability. • The IH-PSB demonstrates a reduction in surface and bottom temperatures by 5.4 °C and 12.1 °C respectively. • The heterogeneous wettability of the IH-PSB enhances its efficiency in moisture condensation and droplet transportation. • The smart roof tile efficiently harnesses waste heat generated by the LEDs while effectively regulating their temperature. [ABSTRACT FROM AUTHOR]

Superhydrophobic (SHPB) materials have attracted a lot of attention in civil engineering due to their unique wettability in recent years. The SHPB characteristics pave up a new way for the applications of SHPB materials in civil engineering. In this review, the applications research progress of SHPB materials in various fields of civil engineering is summarized. The waterproofing, self‐cleaning, anticorrosion, anti‐icing, and antifogging applications of SHPB materials in architectural engineering are discussed. The applications of SHPB materials in road and bridge engineering such as anti‐icing and antiskidding are listed. The applications of SHPB materials in heating and ventilation engineering are ranged from anticondensation, antifrosting to dust removal. The anticorrosion and antibiofouling applications of SHPB materials in structural engineering in marine environment are presented. The key problem of insufficient mechanical and chemical durability of SHPB materials when applied in civil engineering is pointed out, and the application trend of SHPB materials in civil engineering is prospected. Finally, based on the detailed discussion of the applications of SHPB materials in civil engineering, a brief summary is proposed. It is expected that SHPB materials can be widely and systematically applied in civil engineering, making important contributions to multifunctional development of civil engineering in the future. [ABSTRACT FROM AUTHOR]

Black silicon, which is an attractive material due to its optical properties, is prepared mainly by laser inducing in an SF6 atmosphere. Considering the effect of SF6 gas on the environment and human health, here we propose an efficient, economical, and green approach to process large-scale black silicon. In the wavelength range of 0.3–2.5 µm, the role of air could replace SF6 gas to texture black silicon by laser inducing with appropriate processing parameters. Then, to extend the working window of its excellent light-trapping status, laser-plasma shockwave cleaning was introduced to eliminate the deposition and improve the structures and morphology. The results revealed that the micro-nano structures became higher, denser, and more uniform with increasing cleaning times and deteriorating cleaning velocity, which compensated for the role of S atoms from the ambient SF6. Moreover, absorptance above 85% in the wavelength range of 0.3–15 µm was realized using our method. The effect of scanning pitch between adjacent rows on large-scale black silicon was also discussed. Our method realized the ultrahigh absorptance of large-scale black silicon fabricated in air from visible to mid-infrared, which is of significance in the field of optoelectronic devices. [ABSTRACT FROM AUTHOR]

Medical devices are a major component of precision medicine and play a key role in medical treatment, particularly with the rapid development of minimally invasive surgery and wearable devices. Their tissue contact properties strongly affect device performance and patient health (e.g., heat coagulation and slipperiness on surgical graspers). However, the design and optimization of these device surfaces are still indistinct and have no supporting principles. Under such conditions, natural surfaces with various unique functions can provide solutions. This review summarizes the current progress in natural functional surfaces for medical devices, including ultra-slipperiness and strong wet attachment. The underlying mechanisms of these surfaces are attributed to their coupling effects and featured micro-nano structures. Depending on various medical requirements, adaptable designs and fabrication methods have been developed. Additionally, various medical device surfaces have been validated to achieve enhanced contact properties. Based on these studies, a more promising future for medical devices can be achieved for enhanced precision medicine and human health. [ABSTRACT FROM AUTHOR]

Membrane technology is seen as one of the useful strategies for the treatment of oily wastewater, but the membrane fouling in the process of membrane filtration seriously may affect some properties and time‐consuming. Hydrophilic membrane surface can reduce membrane fouling. The appropriate design for membrane composition and surface structure can transform membrane surface with expected performance. In this work, hydrophilic polyvinylidene fluoride (PVDF) membranes with micro‐nanostructure are fabricated by in situ synthesis and layer‐by‐layer assembly strategies. A zeolitic imidazolate framework‐8 (ZIF‐8) and tannic acid are used to construct microstructure and support hydrophilic groups. The water contact angle and water flux of initial PVDF membrane are 110.67° and 6585.7 L m−2 h−1, respectively, while the optimally modified membrane possesses water contact of 14.5° and water flux of 13641.8 L m−2 h−1. The modified membrane not only owns good underwater oil repellency and oil adhesion resistance but also processes good separation performance for surfactant stable oil‐in‐water emulsion. Furthermore, the modified membranes exhibit constant permeability and underwater oleophobicity in cycling experiments and harsh environments, indicating that the modified coating has stability against shedding of the modified materials. This method supports valuable references for MOF application in the field of oil–water separation. [ABSTRACT FROM AUTHOR]

Boiling two-phase transition is considered to be the ultimate effective cooling strategy for the next generation of high-power devices in the near future in various application scenarios, such as power electronics, radar systems, and computer data centers. The liquid-solid interface plays a crucial role in the boiling phase change and the bubble evolvement. This study proposes a novel architecture of micro-nano structures using a unique hybrid dividing zone array, which can not only enhance the onset of nucleate boiling (ONB) and dramatically elevate the heat transfer coefficient (HTC), but also accelerate liquid replenishment, pushing the critical heat flux (CHF) to a much higher level. This is achieved through a superhydrophilic liquid storage zone that provides timely and continuous liquid supplementation for boiling phase change during the drying out period of the most copper surface. Compared to the plain surface copper sample, the proposed hybrid structured sample achieves about 5–7 °C earlier of ONB, up to 293% enhancement of the maximum HTC, and up to 242% improvement of CHF. Overall, this study demonstrates an effective surface enhancement approach that significantly and comprehensively improve boiling heat transfer performance, making it highly promising for cooling high-power applications. • Hybrid micro-nanostructures were constructed using a unique hybrid dividing zone array. • 5–7 °C earlier of onset of nucleate boiling was achieved. • Up to 293% enhancement of the maximum heat transfer coefficient was accomplished. • Up to 242% improvement of critical heat flux was realized. • Stable and continuous boiling was sustained when large bubble fully covering heating surface. [ABSTRACT FROM AUTHOR]

As research on superhydrophobic materials inspired by the self-cleaning and water-repellent properties of plants and animals in nature continues, the superhydrophobic preparation methods and the applications of superhydrophobic surfaces are widely reported. Silicones are preferred for the preparation of superhydrophobic materials because of their inherent hydrophobicity and strong processing ability. In the preparation of superhydrophobic materials, silicones can both form micro-/nano-structures with dehydration condensation and reduce the surface energy of the material surface because of their intrinsic hydrophobicity. The superhydrophobic layers of silicone substrates are characterized by simple and fast reactions, high-temperature resistance, UV resistance, and anti-aging. Although silicone superhydrophobic materials have the disadvantages of relatively low mechanical stability, this can be improved by the rational design of the material structure. Herein, we summarize the superhydrophobic surfaces made from silicone substrates, including the cross-linking processes of silicones through dehydration condensation and hydrosilation, and the surface hydrophobic modification by grafting hydrophobic silicones. The applications of silicone-based superhydrophobic surfaces have been introduced such as self-cleaning, corrosion resistance, oil–water separation, etc. This review article should provide an overview to the bioinspired superhydrophobic surfaces of silicone-based materials, and serve as inspiration for the development of polymer interfaces and colloid science.

In this paper, laser surface treatment of Al alloy was studied by comparison of sandblasting and laser ablation. The effects of laser spot distribution on surface roughness, contact angle, chemical composition and shear strength of Al alloy were analyzed. The experimental results showed that the bonding performance of Al alloy are promoted by controlling the laser spot spacing. When laser spot spacing was smaller than the size of the laser spot, micro–nano composite structures were induced by multiple laser pulses, which would improve shear strength by increasing the contact area between Al alloy and adhesive. Using laser surface treatment, the adhesion properties on Al alloy can be promoted. [ABSTRACT FROM AUTHOR]

[Display omitted] • Micro-nano structures were synthesized by one-step hydrothermal method. • Leaf-like CuInS 2 films were constructed on stainless steel mesh. • Photothermal synergistic conversion of CO 2. • Our technology can make flexible devices for many more applications. One potential sustainable energy conversion technique is the photocatalytic reduction of CO 2 by semiconductors. However, insufficient active sites and low utilization efficiency of solar energy lead to the unsatisfactory effect of photothermal catalytic reduction of CO 2. Thus, in this study, leaf-like CuInS 2 micro-nano structures are prepared on three-dimensional flexible substrate by one-step hydrothermal method to improve the photothermal CO 2 reduction efficiency. Among them, the preparation process of hydrothermal method is simple, energy-saving and efficient. In addition, micro-nano structures can not only provide more active sites for photocatalysts due to their large specific surface area, but also form more pores that can promote electron transfer efficiency. Meanwhile, the introduction of sulfur vacancy can promote the separation of photogenerated carriers and improve the adsorption capacity of CO 2. As a result, the yields of CO 2 reduction to CO and CH 4 by leaf-like CuInS 2 micro-nano structures were 1285.2 μmol/m2/h and 231.4 μmol/m2/h, respectively, under the synergistic action of photothermal. At present, there are few reports about the preparation of CuInS 2 micro-nano structures in flexible stainless steel mesh, which also provides a new idea for the design of efficient photothermal cocatalysts. [ABSTRACT FROM AUTHOR]

Fogging poses a significant challenge, occasionally jeopardizing life safety in automotive and surgical fields. The maintenance of high efficiency in photovoltaic systems necessitates regular cleaning, consuming millions of tons of water annually, rendering it financially burdensome in arid regions. The implementation of glass antireflection is a necessary strategy for enhancing photovoltaic efficiency. Therefore, self-cleaning, antifog and antireflective properties have attracted wide attention. A hierarchical micron-nano structure was fabricated by laser marker fast ablation of Al coated soda lime glass in air. The composition, structure, morphology, transparency, and anti-fog performance of the structured samples were measured and analyzed. The influence of Al coating thickness and laser scanning speed on the resulting surface properties was investigated. The structured surface exhibited a distinct hillock-hollow micro-structure, with widely distributed Al-based nanoparticles covering the entire surface. Consequently, the treated samples demonstrated a water contact angle of 0°, siginfing superhydrophilicity, and exhibited outstanding and durable antifogging properties for over 150 days. Even after 540 days of storage in the laboratory, a noticeable antifog effect persisted for the treated sample compared to the reference, which had degraded substantially. Notably, achieving 0-degree superhydrophilicity took within a mere 1 s for the structured surface, which also showed outstanding antifouling and self-cleaning attributes. Moreover, the treated glass exhibited a broadband transmission enhancement of 2 % in the range of 400–1100 nm compared to the control glass. It is important to highlight that the combination of durable superhydrophilic antifog performance, self-cleaning attribute, and broadband transmission enhancement has not been reported previously for laser-ablated surfaces. This technique exhibits significant potential for wide-ranging applications across multiple fields. • Preparation of micro-nanos tructures by rapid laser ablation of Al coated glass. • The treated surface achieved 0-degree superhydrophilicity within within a mere 1 s. • The treated samples exhibits antifogging properties for over 150 days. • The treated samples exhibits remarkable antifouling and self-cleaning attributes. • The treated glass exhibited a transmission enhancement of 2 % in the range of 400–1100 nm. [ABSTRACT FROM AUTHOR]

Black silicon, which is an attractive material due to its optical properties, is prepared mainly by laser inducing in an SF6 atmosphere. Considering the effect of SF6 gas on the environment and human health, here we propose an efficient, economical, and green approach to process large-scale black silicon. In the wavelength range of 0.3–2.5 µm, the role of air could replace SF6 gas to texture black silicon by laser inducing with appropriate processing parameters. Then, to extend the working window of its excellent light-trapping status, laser-plasma shockwave cleaning was introduced to eliminate the deposition and improve the structures and morphology. The results revealed that the micro-nano structures became higher, denser, and more uniform with increasing cleaning times and deteriorating cleaning velocity, which compensated for the role of S atoms from the ambient SF6. Moreover, absorptance above 85% in the wavelength range of 0.3–15 µm was realized using our method. The effect of scanning pitch between adjacent rows on large-scale black silicon was also discussed. Our method realized the ultrahigh absorptance of large-scale black silicon fabricated in air from visible to mid-infrared, which is of significance in the field of optoelectronic devices.

Biological surfaces in nature, such as lotus leaves, rose petals, and water striders, exhibit excellent superhydrophobicity. The fabrication of superhydrophobic surfaces inspired by nature has become an important research topic. The potential application of superhydrophobic surfaces in many fields has promoted the rapid development of fabrication techniques. Various chemical methods, such as chemical vapor deposition techniques, solution immersion methods, electrochemical techniques, hydrothermal method, and sol–gel process, have been proposed for fabricating superhydrophobic surfaces due to their low cost, simple preparation, and easy promotion. Herein, the progress of chemical fabrication methods of superhydrophobic surfaces in recent years is focused on and the strengths and weaknesses of each technique are analyzed. At last, a brief conclusion of the challenges and perspectives on the fabrication of superhydrophobic surfaces is provided. [ABSTRACT FROM AUTHOR]

Herein, a superhydrophobic Ni coating is prepared on 316L stainless steel by electrodeposition and low energy modification with tetradecanoic acid. After 20 min of electrodeposition with a current density of 8 A dm−2, a Ni coating with micro–nano dual‐scale structures is obtained. The coating becomes superhydrophobic with a water contact angle (WCA) of 160.4° and a sliding angle (SA) of 8.3° after being immersed in the tetradecanoic acid solution (5 g L−1, 12 h). A two‐level structure model is established for explaining the effect of morphology on the wettability of the coating. The WCA value of the superhydrophobic Ni coating retains above 150° after being exposed in outdoor environment for 6 months and in flowing environment for 7 days. In addition, the coating still shows superhydrophobicity after 9 times of mechanical abrasion test, 12 h of acid soaking (pH = 1), and 16 h of heat treatment in 200 °C. Moreover, the coating improves the corrosion resistance of the steel substrate. This superhydrophobic Ni coating provides a simple method to prevent stainless steel from corrosion. And the theoretical calculation of the two‐level model can provide an innovative strategy for designing the structure of the superhydrophobic coating. [ABSTRACT FROM AUTHOR]

In this paper, laser surface treatment of Al alloy was studied by comparison of sandblasting and laser ablation. The effects of laser spot distribution on surface roughness, contact angle, chemical composition and shear strength of Al alloy were analyzed. The experimental results showed that the bonding performance of Al alloy are promoted by controlling the laser spot spacing. When laser spot spacing was smaller than the size of the laser spot, micro–nano composite structures were induced by multiple laser pulses, which would improve shear strength by increasing the contact area between Al alloy and adhesive. Using laser surface treatment, the adhesion properties on Al alloy can be promoted.

• We review the current state of research in femtosecond and nanosecond laser processing of metallic glass surfaces. • The microscopic changes in the material by the action of femtosecond and nanosecond lasers are reviewed. • The mechanisms of micro- and nanostructure evolution on metallic glass surfaces are presented. • The mechanical properties, optical properties, wettability and biocompatibility of metallic glass surfaces after laser irradiation are reviewed and discussed. In recent years, the number of research work on the surface modification of metal glass by laser processing has been increasing, indicating that the interaction between laser and metal glass surface is interesting. Short pulse laser and ultrashort pulse laser processing are the most prominent in this field because of their narrow pulse width, high energy density and short action time with materials. In particular, femtosecond lasers and nanosecond lasers provide great possibilities for high quality, high efficiency and low loss processing of metal glass. This review summarizes this specific research field, introduces the properties and applications of metallic glass, the processing characteristics of femtosecond lasers and nanosecond lasers, and explains the complex process between laser and metallic glass from a microscopic perspective. In addition, this paper also analyzes the micro-nano structure and macroscopic morphology, and discusses the influence of microscopic mechanism on the structure. On the other hand, the properties of micro-nano structure are also discussed, including mechanical properties, optical properties, wettability and biocompatibility, which is of great significance to the surface functionalization of metallic glass. [ABSTRACT FROM AUTHOR]

• Advances in femtosecond laser with etching fabrication of micro-optical components are reviewed. • Wet and dry etching processes for various hard materials are described. • Cutting-edge applications of femtosecond laser with etching are introduced. • Current challenges and future perspective of this field have been discussed. With advantages of small size, light weight, flexible design, and easy mass production, micro-optical components of hard materials have a wide range of potential applications in artificial intelligence, information processing, aerospace, biomedicine, laser technology, etc. However, it is difficult to realize three-dimensional (3D) micro-optical components with complex morphologies. In recent years, femtosecond laser with etching technology has proven to be effective for the fabrication of micro-optical components in hard materials owing to their high precision, high surface quality, and ability to fabricate arbitrary 3D structures. This review focuses on the recent advancements in femtosecond laser with etching fabrication of micro-optical components of various materials. We briefly introduce femtosecond laser modification and summarize the wet and dry etching processes of various materials. According to the types of optical components, the methods and applications of optical components fabricated by femtosecond laser with etching are discussed. The paper concludes with a follow-up and an outlook of femtosecond laser processing in femtosecond laser with etching fabrication of micro-optical components. [ABSTRACT FROM AUTHOR]

[Display omitted] • Copolymers (PNANPF6-PCOE) were prepared by macromolecular cross metathesis method. • Both PNANPF6-PCOE and PNANPF6-PCOE/PP have micro-nano structures. • The blends have migration of fluorinated segments and entanglement of alkyl segments. • Antifouling durability was enhanced by melt-blending process compared with coating. Fluoropolymers are widely used as hydrophobic coatings on plastics, which have low stability and durability. Therefore, it has been a challenge to strengthen the bond force between plastics and fluoropolymers, to improve their chain entanglement, and to make the hydrophobicity of those materials more stable and durable. In this paper, fluorinated multiblock copolymers (PNANPF6-PCOE) with good hydrophobicity, processability and thermal stability were prepared by macromolecular cross metathesis (MCM) method. Notably, micro-nano structures were formed by simply controlling the reaction time of MCM due to the disparity of rigidity and flexibility and polarity in PCOE and PNANPF6 blocks. The micro-nano structures were also preserved in the blends of PNANPF6-PCOE/polypropylene (PP). The tensile mechanical properties and hydrophobicity of PNANPF6-PCOE/PP blends are affected by the length of PCOE and PNANPF6 blocks in multiblock copolymer. With the high temperature in melt-blending process, fluorinated segment groups could easily move and aggregate to the surface, and alkyl groups also would entangle and compatibly blend with polypropylene, which resulted in good thermal properties, well mechanical performance and great hydrophobicity. Most importantly, the antifouling durability to coffee, cola and ethanol was greatly enhanced by melt-blending process compared with solution coating method. This can provide a new strategy for the preparation of fluorinated multiblock copolymers with micro-nano structures, and would demonstrate a new way to achieve durable hydrophobicity and antifouling properties in general materials. [ABSTRACT FROM AUTHOR]

Inspired by the antifouling properties of scaly fish, the conventional silicone coating with phenylmethylsilicone oil (PSO/PDMS) composite coating was fabricated and modified with single layer polystyrene (PS) microsphere (PSO/PDMS-PS) arrays. The fish scale like micro-nano structures were fabricated on the surface of bio-inspired coating, which can reduce the contact area with the secreted protein membrane of fouling organisms effectively and prevent further adhesion between fouling organisms and bio-inspired coating. Meanwhile, PSO exuded to the coating surface has the similar function with mucus secreted by fish epidermis, which make the coating surface slithery and will be polished with the fouling organisms in turbulent waters. Compared to PSO/PDMS coating without any structure and conventional silicone coating, PSO/PDMS-PS showed better antiadhesion activity against both marine bacteria and benthic diatom (Navicula sp.). Additionally, the existence of PS microspheres can reduce the release rate of PSO greatly, which will extend the service life of coating. Compared to PSO/PDMS coating, the sustained release efficiency of PSO/PDMS-PS coating can reach 23.2%. This facile method for fabricating the bio-inspired composite slow-release antifouling coating shows a widely fabricating path for the development of synergistic anti-fouling coating.

Metal oxide semiconductors (MOSs) hold great promise for electronic devices such as gas sensors. The utilization of ZnO as a conductometric gas sensor material can be traced back to its early stages; however, its application has primarily been limited to high-temperature environments. A gas sensor based on highly porous and interconnected 3D networks of ZnO tetrapod (ZnO-T) micro-nano structures was fabricated via an easy chemical vapor deposition (CVD) method. Homemade instruments were utilized to evaluate the gas-sensing of the sample at room temperature. It exhibited good gas-sensing at room temperature, particularly with a response of up to 338.80% toward 1600 ppm ethanol, while also demonstrating remarkable repeatability, stability, and selectivity. Moreover, the unique gas-sensing properties of ZnO-T at room temperature can be reasonably explained by considering the effect of van der Waals forces in physical adsorption and the synergistic effect of carrier concentration and mobility. The aforementioned statement presents an opportunity for the advancement of gas sensors utilizing ZnO at room temperature.

Micro-channel enhanced heat transfer research is a fundamental research of micro-channel heat exchangers. Micro-channel heat exchangers, as a new type of heat exchanger, have extensive applications in high heat flux equipment and micro-devices. In agricultural engineering, solar energy has a wide application in agricultural energy. However, there are many problems in the heat dissipation of solar cells. The use of micro-channel heat exchangers can effectively control the temperature of the solar cells, prolong the service life and improve the power generation efficiency. In addition, micro-channel technology can also be used in heat pump air conditioners. Heat pump air conditioners have many applications in animal husbandry. New heat pump air conditioners have adopted micro-channel condensers, which can significantly increase heat exchange efficiency and save energy. Heat pipe technology can be used in temperature control of grain storage, drying system of agricultural products, etc. With the improvement of manufacturing and processing technology, micro-channel heat pipes have become a research hotspot as a new type of heat pipe. In order to study the effect of micro-nano structures surface on the heat transfer characteristics of micro-channel flow boiling, the CuCl2 solution was used to etch the surface of aluminum micro-channels, and the copper particles deposited on the surface were removed by ultrasonic cleaning to obtain micro-nano structures surface. The contact angle of the surface was measured, droplets were dropped on the surface and quickly spread, the contact angle was approximately 0°, and super hydrophilicity was exhibited. The surface of the micro-nano structures was modified with a fluorosilane solution for a certain period of time, and the surface contact angle was measured to be 160.2°, showing super-hydrophobicity. Only by sanding treatment was smooth surface, and the surface contact angle was measured to be 67.2°, exhibiting hydrophilicity. Flow boiling experiments were performed using three different surface micro-channels. The experimental refrigerant was R141b and the operating pressure was 142 kPa. The whole experimental section can be divided into an aluminum base, a micro-channel, a quartz glass plate and an aluminum cover plate (with a visible window on the aluminum cover plate). At the side of the aluminum base, there were thermocouple measuring holes in the entrance section, the exit section and the middle section. In the middle section was a pair of upper and lower temperature measuring holes with four pairs. There was a temperature measurement hole at the entrance and exit, and a total of 10 thermometer holes. Pressure sensors were installed on the other side of the base entrance and outlet respectively for monitoring inlet and outlet pressure. The micro-channel was composed of 12 parallel rectangular single channels. The width and height of a single channel were 1 and 2 mm, respectively, the interval between channels was 2 mm, and the length of the micro-channel was 240 mm. The mass flow rates were 312.6 and 505.2 kg/(m²·s), and the heat fluxes were 3.42-34.6 kW/m². The effects of micro-nano structures surfaces on the heat transfer characteristics at different mass flow rates and heat fluxes were investigated. The experimental results showed that the super-hydrophobic surface had the best heat transfer characteristics under low heat flux, and the minimum superheat required for the onset of nucleate boiling was the lowest, followed by the super-hydrophilic surface. For the overall average heat transfer coefficient, the super-hydrophobic surface maximum increased the heat transfer coefficient by 31.6% relative to the smooth surface under the condition of low heat flux, and the heat transfer coefficient of the super-hydrophilic surface was the largest when the heat flux was raised to a certain value, the maximum heat transfer coefficient was 20.6% higher than the smooth surface heat transfer coefficient. Compared with the super-hydrophobic surface, the super-hydrophilic surface heat transfer coefficient had a smaller proportion of increase, mainly because the super-hydrophilic surface showed the best heat transfer characteristics in the saturated boiling section, and the saturated boiling section had a much larger heat transfer coefficient than single phase flow and sub-cooled boiling section. The super-hydrophilic and super-hydrophobic surfaces had the same micro-nano structures surface. The micro-nano structures surface increased the vaporization cores and the contact area between the refrigerant and the wall surface. The difference was that the super-hydrophobic surface was modified by the fluorosilane solution. Hydrophilic and hydrophobic properties, which affected the detachment of bubbles, making the heat transfer characteristics show different characteristics: the heat transfer characteristics of the super-hydrophobic surface in the region of low heat flux was the best, and super-hydrophilic surface in the region of high heat flux had the best heat transfer characteristics. To continue to increase the heating power, a large number of bubbles were generated in the micro-channel under high heat flux density. Due to the hydrophobic feature of the super-hydrophobic surface, bubbles did not easily separate, the heat transfer begins to deteriorate, and the heat transfer coefficient gradually decreases, even lower than smooth surface. [ABSTRACT FROM AUTHOR]

Micro-channel enhanced heat transfer research is a fundamental research of micro-channel heat exchangers. Micro-channel heat exchangers, as a new type of heat exchanger, have extensive applications in high heat flux equipment and micro-devices. In agricultural engineering, solar energy has a wide application in agricultural energy. However, there are many problems in the heat dissipation of solar cells. The use of micro-channel heat exchangers can effectively control the temperature of the solar cells, prolong the service life and improve the power generation efficiency. In addition, micro-channel technology can also be used in heat pump air conditioners. Heat pump air conditioners have many applications in animal husbandry. New heat pump air conditioners have adopted micro-channel condensers, which can significantly increase heat exchange efficiency and save energy. Heat pipe technology can be used in temperature control of grain storage, drying system of agricultural products, etc. With the improvement of manufacturing and processing technology, micro-channel heat pipes have become a research hotspot as a new type of heat pipe. In order to study the effect of micro-nano structures surface on the heat transfer characteristics of micro-channel flow boiling, the CuCl2 solution was used to etch the surface of aluminum micro-channels, and the copper particles deposited on the surface were removed by ultrasonic cleaning to obtain micro-nano structures surface. The contact angle of the surface was measured, droplets were dropped on the surface and quickly spread, the contact angle was approximately 0°, and super hydrophilicity was exhibited. The surface of the micro-nano structures was modified with a fluorosilane solution for a certain period of time, and the surface contact angle was measured to be 160.2°, showing super-hydrophobicity. Only by sanding treatment was smooth surface, and the surface contact angle was measured to be 67.2°, exhibiting hydrophilicity. Flow boiling experiments were performed using three different surface micro-channels. The experimental refrigerant was R141b and the operating pressure was 142 kPa. The whole experimental section can be divided into an aluminum base, a micro-channel, a quartz glass plate and an aluminum cover plate (with a visible window on the aluminum cover plate). At the side of the aluminum base, there were thermocouple measuring holes in the entrance section, the exit section and the middle section. In the middle section was a pair of upper and lower temperature measuring holes with four pairs. There was a temperature measurement hole at the entrance and exit, and a total of 10 thermometer holes. Pressure sensors were installed on the other side of the base entrance and outlet respectively for monitoring inlet and outlet pressure. The micro-channel was composed of 12 parallel rectangular single channels. The width and height of a single channel were 1 and 2 mm, respectively, the interval between channels was 2 mm, and the length of the micro-channel was 240 mm. The mass flow rates were 312.6 and 505.2 kg/(m2·s), and the heat fluxes were 3.42-34.6 kW/m2. The effects of micro-nano structures surfaces on the heat transfer characteristics at different mass flow rates and heat fluxes were investigated. The experimental results showed that the super-hydrophobic surface had the best heat transfer characteristics under low heat flux, and the minimum superheat required for the onset of nucleate boiling was the lowest, followed by the super-hydrophilic surface. For the overall average heat transfer coefficient, the super-hydrophobic surface maximum increased the heat transfer coefficient by 31.6% relative to the smooth surface under the condition of low heat flux, and the heat transfer coefficient of the super-hydrophilic surface was the largest when the heat flux was raised to a certain value, the maximum heat transfer coefficient was 20. 6% higher than the smooth surface heat transfer coefficient. Compared with the super-hydrophobic surface, the super-hydrophilic surface heat transfer coefficient had a smaller proportion of increase, mainly because the super-hydrophilic surface showed the best heat transfer characteristics in the saturated boiling section, and the saturated boiling section had a much larger heat transfer coefficient than single phase flow and sub-cooled boiling section. The super-hydrophilic and super-hydrophobic surfaces had the same micro-nano structures surface. The micro-nano structures surface increased the vaporization cores and the contact area between the refrigerant and the wall surface. The difference was that the super-hydrophobic surface was modified by the fluorosilane solution. Hydrophilic and hydrophobic properties, which affected the detachment of bubbles, making the heat transfer characteristics show different characteristics: the heat transfer characteristics of the super-hydrophobic surface in the region of low heat flux was the best, and super-hydrophilic surface in the region of high heat flux had the best heat transfer characteristics. To continue to increase the heating power, a large number of bubbles were generated in the micro-channel under high heat flux density. Due to the hydrophobic feature of the super-hydrophobic surface, bubbles did not easily separate, the heat transfer begins to deteriorate, and the heat transfer coefficient gradually decreases, even lower than smooth surface. [ABSTRACT FROM AUTHOR]

Micro-channel enhanced heat transfer research is a fundamental research of micro-channel heat exchangers. Micro-channel heat exchangers, as a new type of heat exchanger, have extensive applications in high heat flux equipment and micro-devices. In agricultural engineering, solar energy has a wide application in agricultural energy. However, there are many problems in the heat dissipation of solar cells. The use of micro-channel heat exchangers can effectively control the temperature of the solar cells, prolong the service life and improve the power generation efficiency. In addition, micro-channel technology can also be used in heat pump air conditioners. Heat pump air conditioners have many applications in animal husbandry. New heat pump air conditioners have adopted micro-channel condensers, which can significantly increase heat exchange efficiency and save energy. Heat pipe technology can be used in temperature control of grain storage, drying system of agricultural products, etc. With the improvement of manufacturing and processing technology, micro-channel heat pipes have become a research hotspot as a new type of heat pipe. In order to study the effect of micro-nano structures surface on the heat transfer characteristics of micro-channel flow boiling, the CuCl2 solution was used to etch the surface of aluminum micro-channels, and the copper particles deposited on the surface were removed by ultrasonic cleaning to obtain micro-nano structures surface. The contact angle of the surface was measured, droplets were dropped on the surface and quickly spread, the contact angle was approximately 0°, and super hydrophilicity was exhibited. The surface of the micro-nano structures was modified with a fluorosilane solution for a certain period of time, and the surface contact angle was measured to be 160.2°, showing super-hydrophobicity. Only by sanding treatment was smooth surface, and the surface contact angle was measured to be 67.2°, exhibiting hydrophilicity. Flow boiling experiments were performed using three different surface micro-channels. The experimental refrigerant was R141b and the operating pressure was 142 kPa. The whole experimental section can be divided into an aluminum base, a micro-channel, a quartz glass plate and an aluminum cover plate (with a visible window on the aluminum cover plate). At the side of the aluminum base, there were thermocouple measuring holes in the entrance section, the exit section and the middle section. In the middle section was a pair of upper and lower temperature measuring holes with four pairs. There was a temperature measurement hole at the entrance and exit, and a total of 10 thermometer holes. Pressure sensors were installed on the other side of the base entrance and outlet respectively for monitoring inlet and outlet pressure. The micro-channel was composed of 12 parallel rectangular single channels. The width and height of a single channel were 1 and 2 mm, respectively, the interval between channels was 2 mm, and the length of the micro-channel was 240 mm. The mass flow rates were 312.6 and 505.2 kg/(m2·s), and the heat fluxes were 3.42-34.6 kW/m2. The effects of micro-nano structures surfaces on the heat transfer characteristics at different mass flow rates and heat fluxes were investigated. The experimental results showed that the super-hydrophobic surface had the best heat transfer characteristics under low heat flux, and the minimum superheat required for the onset of nucleate boiling was the lowest, followed by the super-hydrophilic surface. For the overall average heat transfer coefficient, the super-hydrophobic surface maximum increased the heat transfer coefficient by 31.6% relative to the smooth surface under the condition of low heat flux, and the heat transfer coefficient of the super-hydrophilic surface was the largest when the heat flux was raised to a certain value, the maximum heat transfer coefficient was 20. 6% higher than the smooth surface heat transfer coefficient. Compared with the super-hydrophobic surface, the super-hydrophilic surface heat transfer coefficient had a smaller proportion of increase, mainly because the super-hydrophilic surface showed the best heat transfer characteristics in the saturated boiling section, and the saturated boiling section had a much larger heat transfer coefficient than single phase flow and sub-cooled boiling section. The super-hydrophilic and super-hydrophobic surfaces had the same micro-nano structures surface. The micro-nano structures surface increased the vaporization cores and the contact area between the refrigerant and the wall surface. The difference was that the super-hydrophobic surface was modified by the fluorosilane solution. Hydrophilic and hydrophobic properties, which affected the detachment of bubbles, making the heat transfer characteristics show different characteristics: the heat transfer characteristics of the super-hydrophobic surface in the region of low heat flux was the best, and super-hydrophilic surface in the region of high heat flux had the best heat transfer characteristics. To continue to increase the heating power, a large number of bubbles were generated in the micro-channel under high heat flux density. Due to the hydrophobic feature of the super-hydrophobic surface, bubbles did not easily separate, the heat transfer begins to deteriorate, and the heat transfer coefficient gradually decreases, even lower than smooth surface. [ABSTRACT FROM AUTHOR]

The scanning path plays a very important and novel breakthrough in preparing optical anti-reflectance micro-nano structures on the surface of NiTi alloy. Compared with simple grids and grating structures, circular structures are more likely to form closed structures under high heat accumulation nanosecond laser processing conditions. These relatively closed circular structures will further help reduce optical reflection performance. In this study, some designed surface micro-nano structures are prepared by nanosecond laser circular scanning, which are the scanning pitch (plan A), the scanning angle (plan B), and the multi-pass scanning (plan C), respectively. The influence of the different micro-nano structures, surface roughness and elemental content on the surface optical anti-reflectance are also investigated. The results indicate that the best optical anti-reflectance micro-nano structures is obtained by 10-pass scanning among plan C. and which is 5% during the measurement wavelength of 400 nm ∼ 800 nm. At the same time, the mechanism is also discussed for changes in the light trapping effect of the laser textured surfaces. [ABSTRACT FROM AUTHOR]

This paper takes micro-nano motors and metamaterials as examples to introduce the basic concept and development of functional micro nano structures, and analyzes the application potential of the micro-nano structure design and manufacturing technology in the petroleum industry. The functional micro-nano structure is the structure and device with special functions prepared to achieve a specific goal. New functional micro-nano structures are classified into mobile type (e.g. micro-nano motors) and fixed type (e.g. metamaterials), and 3D printing technology is a developed method of manufacturing. Combining the demand for exploration and development in oil and gas fields and the research status of intelligent micro-nano structures, we believe that there are 3 potential application directions: (1) The intelligent micro-nano structures represented by metamaterials and smart coatings can be applied to the oil recovery engineering technology and equipment to improve the stability and reliability of petroleum equipment. (2) The smart micro-nano robots represented by micro-motors and smart microspheres can be applied to the development of new materials for enhanced oil recovery, effectively improving the development efficiency of heavy oil, shale oil and other resources. (3) The intelligent structure manufacturing technology represented by 3D printing technology can be applied to the field of microfluidics in reservoir fluids to guide the selection of mine flooding agents and improve the efficiency of mining. [ABSTRACT FROM AUTHOR]

A single step anodizing process is used to produce micro-nano structures on Aluminum (1050) substrates with sulfuric acid as electrolyte. Therefore, surface energy of the anodized layer is reduced using stearic acid modification. Undoubtedly, effects of different parameters including anodizing time, electrical current, and type and concentration of electrolyte on the final contact angle are systemically studied and optimized. Results show that anodizing current of 0.41 A, electrolyte (sulfuric acid) concentration of 15 wt.% and anodizing time of 90 min are optimal conditions which give contact angle as high as 159.2° and sliding angle lower than 5°. Moreover, the study reveals that adding oxalic acid to the sulfuric acid cannot enhance superhydrophobicity of the samples. Also, scanning electron microscopy images of samples show that irregular (bird's nest) structures present on the surface instead of high-ordered honeycomb structures expecting from normal anodizing process. Additionally, X-ray diffraction analysis of the samples shows that only amorphous structures present on the surface. The Brunauer–Emmett–Teller (BET) specific surface area of the anodized layer is 2.55 m 2  g −1 in optimal condition. Ultimately, the surface keeps its hydrophobicity in air and deionized water (DIW) after one week and 12 weeks, respectively. [ABSTRACT FROM AUTHOR]

This study reported on the formation of sub-5-μm microstructures covered on titanium by cracks growth under 10-ns laser radiation at the wavelength of 532 nm and its induced light modification for production of nanostructures. The electric field intensity and laser power density absorbed by commercial pure titanium were computed to investigate the self-trapping introduced by cracks and the effect of surface morphology on laser propagation characteristics. It is found that nanostructures can form at the surface with the curvature radius below 20 μm. Meanwhile, variable laser fluences were applied to explore the evolution of cracks on commercial pure titanium with or without melt as spot overlap number increased. Experimental study was first performed at the peak laser fluence of 1.063 J/cm 2 to investigate the microstructures induced only by cracks growth. The results demonstrated that angular microstructures with size between 1.68 μm and 4.74 μm was obtained and no nanostructure covered. Then, at the peak laser fluence of 2.126 J/cm 2 , there were some nanostructures covered on the melt-induced curved microstructured surface. However, surface molten material submerged in the most of cracks at the spot overlap number of 744, where the old cracks disappeared. The results indicated that there was too much molten material and melting time at the peak laser fluence of 2.126 J/cm 2 , which was not suitable for obtainment of perfect micro-nano structures. On this basis, peak laser fluence was reduced down to 1.595 J/cm 2 and the sharp sub–5 μm microstructures with nanostructures covered was obtained at spot overlap number of 3720. [ABSTRACT FROM AUTHOR]

The wettability of metal surface has been the subject of the intensive research because of its potential applications in many fields. In this paper, a superamphiphobic Zn coating has been fabricated on X90 pipeline steel substrate via a facile composite method including electrodeposition and chemical modification. The contact angles of water and glycerol on such superamphiphobic Zn coating were up to 155.29° and 153.76°, respectively, and the sliding angles were separate about 3° and 5°, demonstrating excellent superamphiphobic property. Moreover, the wettability of the Zn coating in terms of water and glycerol contact angles was closely related to the micro-nano structures with grooves and the chemical composition with fluorinated chain. Besides, the fine structure of the Zn coating was achieved by adjusting the experimental parameters including the deposition time of electrodeposition and the time of chemical modification, and the effect of the parameters on the wettability of the coating was also investigated. Furthermore, the as-prepared superamphiphobic Zn coating showed excellent self-cleaning property and high durability in atmospheric environment for 6 months. The simple method for fabricating such stable superamphiphobic coating can be easily extended to other metals and alloys. [ABSTRACT FROM AUTHOR]

[Display omitted] • The hierarchical micro-nano TiO 2 structure was fabricated by ultraviolet laser. • The evolution of laser irradiation was elucidated by the comprehensive analyses. • A novel wetting mechanism of front water film supplied by microcavity was studied. Ultraviolet laser irradiation is a significant technique for creating functional materials with hierarchical micro-nano morphology. Herein, a facile laser irradiation method is developed to fabricate multi-scale titanium dioxide structures; their morphologies and compositions are evidenced by scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. By analyzing the high-speed photography and spark distribution, we elucidate that the evolution of material ablation state accompanies with the unique spark area and number distribution attributing to the change of laser irradiation intensity, and these microcavities generated in violent ablation play an important role in the supplement of front water film for enhancing water transport performance. Moreover, the comprehensive analysis of equivalent laser intensity on different micro peaks and pits, global statistical data, and high-speed photography reveals the mechanism of microcavity abnormal narrowing with the increase of laser irradiation cycles. This work has significant implications for understanding the creation of micro-nano topology by laser irradiation for enhancing water transport performance and sheds light on application integration of such promising functional surfaces. [ABSTRACT FROM AUTHOR]

Highlights: [•] We fabricated micro-nano TiO2/SiO2 composite films with tailored, repeated and reversible hydrophobic to hydrophilic conversion properties. [•] Hierarchical TiO2/SiO2 composite film enhances surface reversible wettability conversion under UV irradiation. [•] A simple theoretical model was proposed for elucidating the correlation between TiO2/SiO2 size ratio and water contact angle. [Copyright &y& Elsevier]

Inspired by the antifouling properties of scaly fish, the conventional silicone coating with phenylmethylsilicone oil (PSO/PDMS) composite coating was fabricated and modified with single layer polystyrene (PS) microsphere (PSO/PDMS-PS) arrays. The fish scale like micro-nano structures were fabricated on the surface of bio-inspired coating, which can reduce the contact area with the secreted protein membrane of fouling organisms effectively and prevent further adhesion between fouling organisms and bio-inspired coating. Meanwhile, PSO exuded to the coating surface has the similar function with mucus secreted by fish epidermis, which make the coating surface slithery and will be polished with the fouling organisms in turbulent waters. Compared to PSO/PDMS coating without any structure and conventional silicone coating, PSO/PDMS-PS showed better antiadhesion activity against both marine bacteria and benthic diatom (Navicula sp.). Additionally, the existence of PS microspheres can reduce the release rate of PSO greatly, which will extend the service life of coating. Compared to PSO/PDMS coating, the sustained release efficiency of PSO/PDMS-PS coating can reach 23.2%. This facile method for fabricating the bio-inspired composite slow-release antifouling coating shows a widely fabricating path for the development of synergistic anti-fouling coating. [ABSTRACT FROM AUTHOR]

• Ultrasonic cavitation can be used for surface functionalization. • Erosion cavities and embedded SiO 2 nanoparticles form micro-nano structures. • Fabricated superhydrophobic surface has excellent anti-corrosion and repairability. • 3D porous structures with hydrophobicity and lipophilicity are generated. We proposed a novel superhydrophobic fabrication method based on ultrasonic cavitation. The collapse of cavitation bubbles eroded the surface to form a microstructure with high roughness. SiO 2 nanoparticles were then effectively anchored on the surface using cavitation jets to form a micro-nano composite structure. The superhydrophobic performance was evaluated on the basis of the water contact angle (WCA). The proposed method achieved robust superhydrophobic property, and the WCA of copper, brass and 304 stainless steel substrates exceeded 153.3°. The morphology and composition of the superhydrophobic surfaces were characterized using scanning electron microscopes and Fourier transform infrared, respectively. Results revealed that the SiO 2 particles were uniformly dispersed, and a flaw-free state was obtained by the surface. The samples exhibited excellent anti-corrosive durability during ultraviolet and outdoor testing and immersion in different corrosive solutions. The cavity generated by the cavitation erosion can be used as a container to suppress the loss of effective components. The micro-nano double layer structure was retained, and the WCA can be restored to the original level through functionalization again to give low surface energy. The prepared superhydrophobic surface was repairable. In addition, the WCAs of the copper foam and sponge were 157.0° and 159.6°, respectively. [ABSTRACT FROM AUTHOR]

• The micro/nano hierarchical structures were constructed on Zr 55 Cu 30 Ni 5 Al 10 surface. • The alloy surface exhibited both superhydrophobic and superlipophilic properties. • The corrosion resistance of the modified Zr-based BMG was significantly improved. Unlike the high surface energy of traditional metallic materials, metallic glass with amorphous structure have a lower surface energy with a different wettability of solid surfaces. In this work, the micro-nano hierarchical structures were constructed on the Zr 55 Cu 30 Ni 5 Al 10 bulk metallic glass (BMG) surface by electrochemical corrosion and then modified with stearic acid to form both superhydrophobic and superlipophilic surfaces. After the optimized modification conditions, the water contact angle was as high as 169.6 ± 3.5° with a low water sliding angle of 5° and the contact angle of oil on the alloy surface was 5°, respectively. The present work would open a window for the application of bulk metallic glasses in nondestructive liquid transportation and oil-water separation. [ABSTRACT FROM AUTHOR]

• Micro-nano structures are prepared by laser cleaning assisted laser ablation. • Laser cleaning is used to remove oxide deposition and induce micro/nano structure. • A focused ellipse laser spot is applied to solve the problem of new oxide deposition. • The average reflection was reduced to 2.06% from 300 to 2600 nm. • Great enhancement of infrared light absorption of silicon is realized (2.5–16 μm). To meet the ultra-broadband perfect absorption of visible-infrared light on silicon surfaces, a green, efficient and economical method for fabricating multi-scale micro-nano composite structures in ambient air is proposed. We experimentally demonstrate laser cleaning assisted femtosecond laser ablation for fabricating anti-reflection structures. Laser cleaning technology not only effectively eliminates oxide deposition on the laser textured surfaces, but also manufactures the small scale fine-microstructures and nanostructures. A focused ellipse laser spot is innovatively applied to realize large area and energy decays continuously multiple laser cleaning of laser-treated surfaces, and solve the problem that new oxide deposition is generated in the cleaning process. The processing efficiency is also increased by 4.8 times. The average reflectance of 2.06% is reached from 300 to 2500 nm. Great enhancement of infrared light absorption of silicon from 2.5 to 16 μm is realized experimentally. The average reflectance is reduced to 4.98% with a broadband reflectance below 6.6%. Especially, a reflectance below 5.0% from 2.5 to 10 μm and an average reflectance of 4.3% is achieved, which is the least reported to date by laser processing techniques as far as we know. This strategy for anti-reflection structures is excellent candidate for future optoelectronic devices. [ABSTRACT FROM AUTHOR]