Physicists at the University of Massachusetts Amherst have unveiled novel shape-recovering liquids that contravene long-established thermodynamic principles, challenging prevailing scientific assumptions.
This visual depicts emulsion droplets assiduously stabilized by silica nanoparticles, with residual nickel nanoparticles adorning the droplet exteriors. The visual attribution is credited to Raykh et al., with the associated digital object identifier being 10.1038/s41567-025-02865-1.
Professor Thomas Russell of the University of Massachusetts Amherst drew an analogy to a familiar culinary preparation: “Envision your preferred Italian vinaigrette.”
“This dressing comprises oil, water, and seasonings, which are commingled through vigorous agitation prior to its application on a salad.”
“It is precisely these seasonings, these minute particulate components, that facilitate the amalgamation of oil and water, substances typically immiscible. This phenomenon, known as emulsification, is conventionally elucidated by the laws of thermodynamics.”
“The principle of emulsification serves as a foundational element for an extensive array of technologies and practical applications extending well beyond culinary uses,” stated Anthony Raykh, a postgraduate researcher at the University of Massachusetts Amherst.
“During a laboratory session, I found myself synthesizing a variant of this scientific emulsion, intending to explore novel material creations. Instead of conventional seasonings, I incorporated ferromagnetic nickel particles, recognizing the potential for engineering diverse materials with advantageous properties when a liquid medium incorporates magnetic constituents.”
“Upon preparing the mixture and agitating it, a completely unexpected outcome emerged: the mixture spontaneously coalesced into an elegant, well-defined urn-like configuration.”
“Regardless of the intensity or frequency of agitation, the distinctive urn morphology consistently reasserted itself.”
Through supplementary laboratory investigations and sophisticated computational modeling, the research cadre ascertained that intense magnetic forces are indeed responsible for this inexplicable observed behavior.
“A detailed examination of the individual nanoscale particles of magnetized nickel, which delineate the interface between the aqueous and oleaginous phases, yields exceptionally granular insights into the mechanisms governing diverse structural assemblies,” commented Professor David Hoagland, also affiliated with the University of Massachusetts Amherst.
“In this specific scenario, the magnetic attraction between the particles is sufficiently potent to disrupt the emulsification process, which is typically governed by thermodynamic dictates.”
Ordinarily, the introduction of particles into an oil-water mixture serves to diminish the interfacial tension, thereby promoting miscibility.
However, in a noteworthy deviation, particles possessing a pronounced magnetic characteristic actually augment the interfacial tension, inducing a curvature in the boundary separating the immiscible liquids into a refined arc.
“When confronted with an observation that appears contrary to established principles, rigorous inquiry becomes imperative,” Professor Russell emphasized.
“Although immediate practical applications for our discovery are not yet apparent, we are highly optimistic about the potential impact of this unprecedented state on the domain of soft-matter physics,” Raykh elaborated.
The research findings disseminated by the collective are featured in the esteemed journal Nature Physics, accessible via the following link: work.
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A. Raykh et al. Shape-recovering liquids. Nat. Phys, published online April 4, 2025; doi: 10.1038/s41567-025-02865-1
