Facile Fabrication of a Superhydrophobic Cu Surface via a Selective Etching of High-Energy Facets

The Cu surface with a dual-scale roughness has been prepared via a facile solution-phase etching route by the H₂O₂/HCl etchants. The selective etching of the high-energy {110} facets occurs at an ultralow rate of the redox etching reaction. The resultant surface is composed of many polyhedral microprotrusions and nanomastoids on the microprotrusions, exhibiting the binary micro/nanostructures. After hydrophobization, the resultant surface exhibits a water contact angle of 170° and a sliding angle of ∼2.8° for a 5 μL droplet. The combination of the dual-scale roughness and the low surface energy of the adsorbed stearic acid accounts for the superhydrophobicity. Such a superhydrophobic Cu surface has an excellent nonsticking behavior and anticorrosion against electrolyte solution. It also keeps its superhydrophobic ability after a long-time ultrasonication or abrasion test. Our work may shed light on the selective etching of other metal surfaces to create designed dual-scale roughness for superhydrophobicity

Carbon pools of different land-use types in InVEST (units: MgC•ha⁻¹).

<p>‘<i>Ca</i>’ refers to the aboveground biomass. ‘<i>Cb</i>’ refers to the belowground biomass. ‘<i>Cs</i>’ refers to the soil organic carbon. ‘<i>Cd</i>’ refers to the dead organic matter.</p

Chemoselectivity Streamlines the Approach to Linear and Y‑Shaped Thiol-Polyethers Starting from Thiocarboxylic Acids

Thiol-functionalized polyethers, especially poly(ethylene oxide) (PEO), have extensive applications in biomedicine and materials sciences. Herein, we report a simple one-pot synthesis of α-thiol-ω-hydroxyl polyethers through ring-opening polymerization (ROP) of epoxides using thiocarboxylic acid initiators followed by in situ aminolysis. The efficient and chemoselective metal-free Lewis pair catalyst avoids transthioesterification thus achieving well-controlled molar mass, low dispersity, and high end-group fidelity. Kinetic and calculation results demonstrated a fast-initiation mode of the ROP for the strong nucleophilicity of the thiocarboxylate anion and its weak interaction with Lewis acid. The method is expanded for α-thiol-ω-dihydroxyl (Y-shaped) PEO by virtue of the stability of thioester during the ROP. The thiol functionality in linear/Y-shaped PEO is further corroborated by the intensified interaction with gold surface and the resultant protein resistance behavior

General modeling framework of the integrated SD-CLUE-S and InVEST model.

General modeling framework of the integrated SD-CLUE-S and InVEST model.</p

Oasis carbon storage based on InVEST and land-use change in 2000, 2009, S1, S2, and S3.

<p>Oasis carbon storage based on InVEST and land-use change in 2000, 2009, S1, S2, and S3.</p

Predicted land demand area in the oasis under three scenarios from 2009 to 2018 (units: km²).

<p>Predicted land demand area in the oasis under three scenarios from 2009 to 2018 (units: km²).</p

Simulations of oasis land use in 2018 under scenarios S1, S2, and S3.

<p>Simulations of oasis land use in 2018 under scenarios S1, S2, and S3.</p

Location of Zhangye oasis.

<p>Location of Zhangye oasis.</p

Scenario design based on critical indicators in the study area.

<p>‘S1’ is the historical land-use demand scenario reflecting land demand growth as a continuation of the historical period. ‘S2’ is the moderate protection scenario in which land demand growth was limited by setting critical indicators of economic and social development. ‘S3’ is the strict protection scenario in which land demand growth was simulated with multiple strict protections in the study area.</p

Eco-Friendly Fabrication of Superhydrophobic Bayerite Array on Al Foil via an Etching and Growth Process

In this work, we present a clean and atom-economic fabrication of superhydrophobic Al surfaces, where the Al­(III) ions etched off by OH^– can be transformed to a bayerite array growing out of the Al substrate with the help of CO₂ in air. The resultant array is composed of bayerite microneedles with nanosteps on their surfaces, exhibiting binary micro/nanostructures. The formation mechanism of the microneedles follows a fast etching and subsequent kinetic growth route, significantly different from the traditional etching route. After the chemisorption of steric acid, the resultant Al surface shows a water contact angle of 167° and a sliding angle of ∼3° for a 5 μL water droplet. The dual-scale roughness together with the low surface energy of stearic acid accounts for the superhydrophobicity. The resultant Al surface has an anticorrosion against electrolyte solution and robust repellence against acidic or alkali droplets. It also maintains hydrophobicity after ultrasonication treatment