The new study demonstrates the role of intermolecular forces in the development of sensors

Researchers are further modifying the relationship between water and stability based on molecular strength.

The relationship between the surface of clean water and the moisture content of it. Available: Nano Research

A new study by researchers from the Chinese Academy of Sciences will further explain how water retains their relationship with solid surfaces – also known as wettability – from a strong intermolecular perspective.

The information is published in Nano view and Feb 8.

Wettability is related to the design of the assets in order to determine the relevance of the classes. According to researcher and physician Ye Tian from the Key Laboratory of Bio-inspired Materials and Interfacial Science, “it plays an important role in many aspects, such as the effectiveness of the catalytic effect, separation, electrodes, and the development of bionic sensors. ” For example, smart boards can be used to change their relationship due to the moisture in sports clothes to change the low.

Blue models

The high velocity means the spread of a drop of water, forming a low angle of contact with the skin, while the low velocity describes a water droplet that resists the spread. Typically, wettability is determined, as indicated by the correlation coefficient, using Young’s model, which represents a very good skin. If a drop of water spreads to an angle below 90 degrees, the skin is considered hydrophilic or water -loving. If the water drop is higher than 90 degrees, the skin is considered hydrophobic.

However, Young’s model has limitations in describing the nature of liquids in contact with hard surfaces. For example, she can’t explain why the watery corners rise after the skin is sour, as explained in the last example of Wenzel and Cassie. The authors further investigated the interaction of solid surfaces embedded in clean water at a molecular level to better understand the nature of intrinsic water thresholds (IWTs) – the points where they spread. water or bead. According to Tian “a series of studies have shown that hydrophobic repulsion between the apolar surfaces and hydrophilic repulsion between the polar surface (s) in water can be obtained, i.e., IWTs are necessary. rely on intermolecular forces. “

Researchers are further modifying the relationship between water and stability based on molecular strength.

Apply the corners on the smooth skins and skins for three liquids (ac); the relationship between the surface of clean water and the wet thresholds within (d). Available: Nano Research

Cleaning thresholds

The researchers experimented with the interaction of solids in thick single-molecule layers (self-assembled monolayers or SAM) in different liquids to see how the solids soaked. they are interested or reluctant. They chose water, ethylene glycol (EG), dimethyl sulfoxide (DMSA), and N, N-dimethyl formamide (DMF) as the test fluids to show the nature of the skin’s nerves. Using an atomic strength microscope, they measured the strength buttons for adhesion strengths between the SAMs in each liquid. The contact angles were evaluated for 1 μL droplets of each liquid using an Angle Contact System, a tool that measures the contact angle and the contact angle with stability.

The results showed that for water, the intrinsic pressure threshold (IWT) was found at an angle of 65 ° with constant, not the 90 ° predicted by Young’s model. In other words, 65 ° is the median between the hydrophilic and hydrophobic process, which is related to the differences in the hydrogen retention cells of the water on each side of the threshold. In addition, they observed differences in the adhesion strengths between the liquid layer and solid surfaces (SAM) with a change at a relative angle of about 65 °. Tian explained, “We verified that the IWT for clean water is about 65 ° from the point of view of the relative powers between the symmetrical SAMs.”

Other natural liquids do not have hydrogen bonds, however, IWTs are obtained by observing changes in adhesion strengths between solid surfaces (SAM) and contact angles. The results provide that “a new set of IWTs, different from the value described by Young’s model, can be used to judge IWTs for clean water with the presence of skin color. Skin. “

The next steps

Researchers plan to continue to study the functions of wool at a primary level, given the significant demands in the design of tools. After further elaborating on the IWTs in relation to Young’s historical model, they hope to “provide a new perspective to understand the relationship between wettability and intermolecular strength,” Tian predicts.


Sapphires show their true colors: They don’t need water


More information:
Yulong Li et al, Investigating the actual purification thresholds of water by measuring the relative strengths of the combined monolayers, Nano view (2022). DOI: 10.1007 / s12274-022-4094-z

Presented by Tsinghua University Press

Directions: New research shows how intermolecular influences influence the development of intelligent beings (2022, April 8) retrieved 9 April 2022 from https://phys.org/news/2022-04-reveals -intermolecular-smart-materials.html

This document is subject to copyright. Except for appropriate work for the purpose of personal inquiry or research, no piece may be reproduced without permission. Information is provided for informational purposes only.

Related Posts

Leave a Reply

Your email address will not be published.