#electrothermal

Precision in miniature: New microgripper technology for electronics assembly

Microgrippers are essential tools for manipulating minute objects, with applications ranging from medical biopsies to microassembly in electronics. However, traditional microgripper technologies have faced significant limitations, including reliance on complex light sources, high voltages, and bulky magnetic systems. These constraints often hinder their use in confined or specialized microenvironments. The growing need for more versatile, efficient, and user-friendly microgrippers has driven recent research efforts toward overcoming these barriers. A team of researchers led by Professor Huikai Xie from Beijing Institute of Technology recently published their study in Microsystems & Nanoengineering. This study was primarily done by Prof. Xie's Ph.D. student Hengzhang Yang who is the first author of the paper. Their novel electrothermal microgripper, based on Al-SiO2 bimorphs, combines remarkable deformation and rapid response capabilities while consuming minimal power, offering a promising solution to the challenges faced by traditional technologies.

Engineers weave advanced fabric that can cool a wearer down and warm them up

Textile engineers have developed a fabric woven out of ultra-fine nano-threads made in part of phase-change materials and other advanced substances that combine to produce a fabric that can respond to changing temperatures to heat up and cool down its wearer depending on need.

Materials scientists have designed an advanced textile with nano-scale threads containing in their core a phase-change material that can store and release large amounts of heat when the material changes phase from liquid to solid. Combining the threads with electrothermal and photothermal coatings that enhance the effect, they have in essence developed a fabric that can both quickly cool the wearer down and warm them up as conditions change.

A paper describing the manufacturing technique appeared in ACS Nano on August 10.

Many occupations, from firefighters to farmworkers, involve harsh hot or cold environments. Cold storage, ice rinks, steel forges, bakeries, and many other job sites require workers to make frequent transitions between different and sometimes extreme temperatures. Such regular temperature changes are not only uncomfortable but can cause illness or even injury, and require a cumbersome constant change of clothing. A sweater will keep a worker warm in a cold meat locker, but could overheat the same worker when they leave that space.

Researchers develop a novel 2D material that uses a virus to kill cancer cells

Electro-thermal therapy, which involves applying electrical signals to nanomaterials, provides high cancer cell targeting accuracy and is highly bio-compatible. In this research, scientists from the Singapore University of Technology and Design (SUTD) have designed a novel thermal-based therapy nano-system that destroys more than 20% of pancreatic cancer cells using microsecond electrical pulses and with excellent bio-compatibility.

Electro-thermal therapy works by injecting two dimensional (2D) materials in cancer cells and applying electrical currents to the cells. This causes the materials to heat up and kill neighboring cancer cells. Traditional electro-thermal therapy with 2D materials however, can fail as a result of weak cancer cell ablation. This is due to the limited amount of materials assembled on the cancer cells and the weak Joule heating generated in the material.

To alleviate these issues, the researchers deposited the M13 virus on molybdenum disulfide (MoS2) layered materials to create a hybrid nanomaterial MoS2 Nanostructure with M13 virus (the authors call it MNM). Moreover, they altered the nanomaterial surfaces with polyethylene glycol (PEG) to improve bio-compatibility.

Carbon fabric (CF) is one type of high performance carbon fibers with a carbon content of more than 95%, which possesses a series of compelling properties, such as high specific strength, high thermal stability, excellent electrical conductivity, and superior fatigue resistance. CF can be an ideal material choice to serve as a favorable electrical heating element in a heater with distinctive features of better air-permeability, flexibility and Wear ability. Woolen yarn is also widely used as a material for heating products due to its good thermal insulation effects.

Currently, most heating products to address the warmth retention issues are fabricated with solar energy heating materials, phase change materials, chemical energy heating materials, and electric heating materials to store or generate heat.

The electrothermal fabric could achieve a steady-state temperature of 75.4 °C in 30 s under 10 V voltage. designed cotton fabrics coated with graphene/ polyurethane composite using pad-dry-cure process. This process enhanced the far-infrared emissivity up to 0.911 and the obtained fabrics reached the destination temperature of 100 °C in 5 min 58 s.

It is highly desirable to explore more facile and versatile techniques to develop highly flexible and efficient infrared radiation heating textiles with advanced material selection and rational structure design.

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