Laser Ablation and Chemical Oxidation Synergistically Induced Micro/Nano Re-entrant Structures for Super-Oleophobic Surface with Cassie State

Generally,re-entrant structures are a key part of fabricating superoleophobic surfaces,and this structure appears in almost all kinds of published research articles regarding superoleophobicity.However,the application of related fabrication methods is usually too complex and costly in real practice.In this paper,we present a simple method to generate micro-cauliflower structures,which work as re-entrant structures in microcone arrays,to promote the formation of superoleophobic surfaces.The heating process after alkali-assisted surface oxidation is the main reason for the appearance of a micro-ball structure,and the oxidation time can influence the size of the micro-ball.To the best of our knowledge,the influence of the heating process after alkali-assisted surface oxidation on the birth of the micro-ball structure is seldom researched.A low-surface-energy treatment was also analyzed in influencing the size of the re-entrant structure and its relative wettability.Droplets of 5μl of n-decane show contact angles of 155±1°on the as-prepared superoleophobic surface,and air pockets can be clearly seen underneath,indicating a stable Cassie contacting state and a promising application value in the near future.

High-Performance Aqueous Zinc-Ion Battery Based on Laser-Induced Graphene

Zn-ion batteries(ZIBs)have a broad application prospect because of their advantages of high power,large capacity,and high energy density.However,the development of high-capacity,long-lifespan ZIBs is challenging because of the faster dendrite growth and the occurrence of the hydrogen evolution reaction.Laser-induced graphene(LIG)is a material with many defects and heteroatoms.Because of these characteristics,it plays an important role in improving nucleation.A simple and effective method for preparing LIG was proposed in this paper,and the LIG was covered on the surface of Zn foil to form a composite structure.This structure substantially reduces the nucleation overpotential of Zn and slows down the dendrite growth of Zn by improving the nucleation behavior of Zn^(2+).Simultaneously,the three-dimensional porous structure increases the specific surface area of the electrode,so the battery has a larger specific capacity.Compared with the bare Zn electrode,the composite electrode possesses lower overpotential and longer cycle life.In addition,the full battery using activated carbon as the active material exhibits great rate and cycle performance.This facile and scalable approach may solve the problem of Zn dendrite growth,which is crucial for the large-scale application of ZIBs.

Recent progress in bio-inspired macrostructure array materials with special wettability—from surface engineering to functional applications

Bio-inspired macrostructure array(MAA,size:submillimeter to millimeter scale)materials with special wettability(MAAMs-SW)have attracted significant research attention due to their outstanding performance in many applications,including oil repellency,liquid/droplet manipulation,anti-icing,heat transfer,water collection,and oil–water separation.In this review,we focus on recent developments in the theory,design,fabrication,and application of bio-inspired MAAMs-SW.We first review the history of the basic theory of special wettability and discuss representative structures and corresponding functions of some biological surfaces,thus setting the stage for the design and fabrication of bio-inspired MAAMs-SW.We then summarize the fabrication methods of special wetting MAAs in terms of three categories:additive manufacturing,subtractive manufacturing,and formative manufacturing,as well as their diverse functional applications,providing insights into the development of these MAAMs-SW.Finally,the challenges and directions of future research on bio-inspired MAAMs-SW are briefy addressed.Worldwide efforts,progress,and breakthroughs from surface engineering to functional applications elaborated herein will promote the practical application of bio-inspired MAAMs-SW.

Dodecyl Mercaptan Functionalized Copper Mesh for Water Repellence and Oil-water Separation

Reckless discharge of industrial wastewater and domestic sewage as well as frequent leakage of crude oil have caused serious environmental problems and posed severe threat to human survival.Various nature inspired superhy-drophobic surfaces have been successfully applied in oily water remediation.However,further improvements are still urgently needed for practical application in terms of facile synthesis process and long-term durability towards harsh environment.Herein,we propose a simple one-step dodecyl mercaptan functionalization method to fabricate Super-hydrophobic-Superoleophilic Copper Mesh(SSCM).The prepared SSCM possesses excellent water repellence and oil affinity,enabling it to successfully separate various oil-water mixtures with high separation efficiency(e.g.,>99%for hexadecane-water mixture).The SSCM retains high separating ability when hot water and strong corrosive aqueous solutions are used to simulate oil-water mixtures,indicating remarkable chemical durability of the dodecyl mercaptan functionalized copper mesh.Additionally,the efficiency can be well maintained during 50 cycles of separation,and the water repellence is even stable after storage in air for 120 days,demonstrating the reusability and long-term stability of the SSCM.Furthermore,the functionalized mesh also shows good mechanical robustness towards abrasion by sandpaper,and oil-water separation efficiency of>96%can be obtained after 10 cycles of abrasion.The reported one-step dodecyl mercaptan functionalization could be a simple method for increasing the water repellence of copper mesh,and thereby be a great candidate for treating large-scale oily wastewater in harsh environments.