Regioselective magnetization enabled chiral semiconducting heteronanorods

February 25, 2020

The USTC team led by Prof. Shu-Hong Yu (USTC), collaborating with Prof. Zhiyong Tang (National Center for Nanoscience and Technology, China) and Prof. Edward H. Sargent (University of Toronto), has shed new lights on the topic of chiral inorganic nanomaterials. Researchers demonstrated a regioselective magnetization strategy, achieving a library of semiconducting heteronanorods with chiroptical activities.

The research article entitled "Regioselective magnetization in semiconducting nanorods" was published in Nature Nanotechnology on Jan 20th.

Chirality - the property of an object non-superimposable with its mirror image - is of widespread interest in physics, chemistry, and biology. The chiroptical activity in materials can be tuned by electric and magnetic transition dipoles. To date, the chemical construction of chiral nanomaterials has been achieved through the introduction of chiral molecules and geometrically helical structures to provide modulation; but these methods limit their environmental instability - chirality disappears under illumination, heating, or in a harsh chemical environment - and poor conductivity, since charge transfer processes towards surface reactants and electrodes are impeded. These limitations hamper further practical applications of chiral materials in various areas.

Designing magneto-optical nanomaterials offers an opportunity to modulate the interactions between electric and magnetic dipoles via the local magnetic field, underlining another promising approach to enable chirality. To materialize such chiroptically active media, the growth of magnetic units has to be achieved at targeted locations of parent nanomaterials. One-dimensional chalcogenide semiconductor nanorods stand out as compelling candidates to serve as the parent materials due to their high geometric anisotropy, large electric dipole moment along nanorods, ease of composition and size modulations, as well as promising applications in catalysis, photonics, and electronics. However, technical challenges lie in the epitaxial growth between host and motif materials of large lattice and chemical mismatches, let alone the regioselective growth.

Taking up the challenge, researchers reported a double-buffer-layer engineering strategy to achieve the selective growth of magnetic materials at specific locations on a wide variety of semiconducting nanorods (i.e. ZnxC1-xS, where 0?x?1). The authors sequentially integrated Ag2S and Au intermediate layers at one apex of each nanorod to catalyze the site-specific growth of Fe3O4 nanodomains. Due to the location-specific magnetic field, the resulting magnetized heteronanorods exhibit deflected electric dipole moment. In this way, the non-zero interaction between electric and magnetic transition dipoles induces chiroptical activity in the absence of chiral ligands, helical structures, and chiral lattices - a phenomenon not observed outside of modulation. The regioselective magnetization strategy opens a new avenue to designing optically active nanomaterials for chirality and spintronics.

University of Science and Technology of China

Related Nanorods Articles from Brightsurf:

Laser-powered nanomotors chart their own course
The University of Tokyo introduced a system of gold nanorods that acts like a tiny light-driven motor, with its direction of motion is determined by the orientation of the motors.

Controlling ultrastrong light-matter coupling at room temperature
Physicists at Chalmers University of Technology in Sweden, together with colleagues in Russia and Poland, have managed to achieve ultrastrong coupling between light and matter at room temperature.

Round nanoparticles improve quality factors of surface lattice resonances: Study
A research group led by Dr. LI Guangyuan from the Shenzhen Institutes of Advanced Technology (SIAT) of the Chinese Academy of Sciences has found that nanohemisphere arrays can significantly improve the quality factors of surface lattice resonances.

Nanomaterial gives robots chameleon skin
A new film made of gold nanoparticles changes color in response to any type of movement.

New tool helps nanorods stand out
Rice University scientists introduce an open-source method to simplify nanoparticle analysis using scanning electron microscope images.

Researchers promote cancer cell growth in the near infrared region by using silica coated gold nano
In a report published in NANO, a group of researchers from the Republic of Korea have discovered a method to promote cancer cell growth using silica-coated gold nanorods.

Expanding the plasmonic painter's palette
By blending paints in their palette, artists can create a broad spectrum of colors with subtly different hues.

Regioselective magnetization enabled chiral semiconducting heteronanorods
Researchers demonstrated a regioselective magnetization strategy, achieving a library of semiconducting heteronanorods with chiroptical activities.

A megalibrary of nanoparticles
Using straightforward chemistry and a mix-and-match, modular strategy, researchers have developed a simple approach that could produce over 65,000 different types of complex nanoparticles.

Illuminating the world of nanoparticles
Scientists at the Okinawa Institute of Science and Technology Graduate University (OIST) have developed a light-based device that can act as a biosensor, detecting biological substances in materials; for example, harmful pathogens in food samples.

Read More: Nanorods News and Nanorods Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to