2021 New's Items

Surface chemistry of hot electron and metal-oxide interfaces

Lee SW
Lee H
Park Y
Kim H
Somorjai GA
Park JY
2021

Fundamental mechanisms for energy conversion and dissipation on surfaces and at interfaces have been significant issues in the community of surface science. Electronic excitation in exothermic chemical reactions or photon absorption involves the generation of energetic or hot electrons that are not in thermal equilibrium via non-adiabatic electronic excitation. A number of experimental and theoretical studies have demonstrated the influence of excited hot electrons on atomic and molecular processes, and it is a key moderator in the surface energy conversion process. The charge...

Insights into the Mechanism of Methanol Steam Reforming Tandem Reaction over CeO2 Supported Single-Site Catalysts

Chen L
Qi Z
Peng X
Chen JL
Pao CW
Zhang X
Dun C
Young M
Prendergast D
Urban JJ
Guo J
Somorjai GA
Su J
2021

We demonstrated how the special synergy between a noble metal single site and neighboring oxygen vacancies provides an “ensemble reaction pool” for high hydrogen generation efficiency and carbon dioxide (CO2) selectivity of a tandem reaction: methanol steam reforming. Specifically, the hydrogen generation rate over single site Ru1/CeO2 catalyst is up to 9360 mol H2 per mol Ru per hour (579 mLH2 gRu–1 s–1...

A non-unitary metasurface enables continuous control of quantum photon–photon interactions from bosonic to fermionic

Li Q
Bao W
Nie Z
Xia Y
Xue Y
Wang Y
Yang S
Zhang X
2021

Photonic quantum information processing, one of the leading platforms for quantum technologies1,2,...

Unprecedented Fluorophore Photostability Enabled by Low-Loss Organic Hyperbolic Materials

Lee YU
Li S
Bopp SE
Zhao J
Nie Z
Posner C
Yang S
Zhang X
Zhang J
Liu Z
2021

The dynamics of photons in fluorescent molecules plays a key role in fluorescence imaging, optical sensing, organic photovoltaics, and displays. Photobleaching is an irreversible photodegradation process of fluorophores, representing a fundamental limitation in relevant optical applications. Chemical reagents are used to suppress the photobleaching rate but with exceptionally high specificity for each type of fluorophore. Here, using organic hyperbolic materials (OHMs), an optical platform to achieve unprecedented fluorophore photostability without any chemical specificity is...

Mark Stockman: Evangelist for Plasmonics

Aizpurua J
Atwater HA
Zhang X
Zheludev NI
2021

Mark Stockman was a founding member and evangelist for the plasmonics field for most of his creative life. He never sought recognition, but fame came to him in a different way. He will be dearly remembered by colleagues and friends as one of the most influential and creative contributors to the science of light from our generation.

Observation of strong excitonic magneto-chiral anisotropy in twisted bilayer van der Waals crystals

Lan S
Liu X
Wang S
Zhu H
Liu Y
Gong C
Yang S
Shi J
Wang Y
Zhang X
2021

The interplay between chirality and magnetism generates a distinct physical process, the magneto-chiral effect, which enables one to develop functionalities that cannot be achieved solely by any of the two. Such a process is universal with the breaking of parity-inversion and time-reversal symmetry simultaneously. However, the magneto-chiral effect observed so far is weak when the matter responds to photons, electrons, or phonons. Here we report the first observation of strong magneto-chiral response to excitons in a twisted bilayer tungsten disulfide with the amplitude of excitonic...

Nonlinear valley phonon scattering under the strong coupling regime

Liu X
Yi J
Yang S
Lin EC
Zhang YJ
Zhang P
Li JF
Wang Y
Lee YH
Tian ZQ
Zhang X
2021

Research efforts of cavity quantum electrodynamics have focused on the manipulation of matter hybridized with photons under the strong coupling regime1,2...

Nanocrystals as Model Systems for Studying the Interplay Between Crystallization and Chirality

Hananel U
Moshe AB
Markovich G
Alivisatos AP
2021

The interplay between crystallization and chirality has fascinated chemists for over 170 years now. Many questions deal with the transfer of chirality from molecular level building blocks and crystal capping ligands to the macroscopic morphologies of crystals. Also the interest in nanoscale chiral crystallization and the relationship between chiral ligands and inorganic nanocrystals has recently arose. In this review we highlight several different topics related to studies of the interplay between chirality and crystallization that involve inorganic nanocrystals. Specifically,...

Atomic-scale ion transistor with ultrahigh diffusivity

Xue Y
Xia Y
Yang S
Y. Alsaid
Fong KY
Wang Y
Zhang X
2021

Biological ion channels rapidly and selectively gate ion transport through atomic-scale filters to maintain vital life functions. We report an atomic-scale ion transistor exhibiting ultrafast and highly selective ion transport controlled by electrical gating in graphene channels around 3 angstroms in height, made from a single flake of reduced graphene oxide. The ion diffusion coefficient reaches two orders of magnitude higher than the coefficient in bulk water. Atomic-scale ion transport shows a threshold behavior due to the critical energy barrier for hydrated ion insertion. Our in...

Topological Corner Modes Induced by Dirac Vortices in Arbitrary Geometry

Wu X
Meng Y
Hao Y
Zhang RY
Li J
Zhang X
2021

Recently, higher-order topologies have been experimentally realized, featuring topological corner modes (TCMs) between adjacent topologically distinct domains. However, they have to comply with specific spatial symmetries of underlying lattices, hence their TCMs only emerge in very limited geometries, which significantly impedes generic applications. Here, we report a general scheme of inducing TCMs in arbitrary geometry based on Dirac vortices from aperiodic Kekulé modulations. The TCMs can now be constructed and experimentally observed in square and pentagonal domains incompatible...