As a remarkable class of plasmonic materials, two dimensional (2D) semiconductor compounds have attracted attention owing to their controlled manipulation of plasmon resonances in the visible light spectrum, which outperforms conventional noble metals. However, tuning of plasmonic resonances for 2D semiconductors remains challenging. Herein, we design a novel method to obtain amorphous molybdenum oxide (MoO ) nanosheets, in which it combines the oxidation of MoS and subsequent supercritical CO -treatment, which is a crucial step for the achievement of amorphous structure of MoO . Upon illumination, hydrogen-doped MoO exhibits tuned surface plasmon resonances in the visible and near-IR regions. Moreover, a unique behavior of the amorphous MoO nanosheets has been found in an optical biosensing system; there is an optimum plasmon resonance after incubation with different BSA concentrations, suggesting a tunable plasmonic device in the near future.

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Amorphous MoO3−x nanosheets with enhanced LSPR are fabricated by introducing Mo atoms into the interlayers of MoO3via a hydrothermal and post-irradiation method, which is beneficial for photo-to-heat conversion.

Two-dimensional (2D) semiconductors have recently emerged as a remarkable class of plasmonic alternative to conventional noble metals. However, tuning of their plasmonic resonances towards different wavelengths in the visible-light region with physical or chemical methods still remains challenging. In this work, we design a simple room-temperature chemical reaction route to synthesize amorphous molybdenum oxide (MoO ) nanodots that exhibit strong localized surface plasmon resonances (LSPR) in the visible and near-infrared region. Moreover, tunable plasmon resonances can be achieved in a wide range with the changing surrounding solvent, and accordingly the photoelectrocatalytic activity can be optimized with the varying LSPR peaks. This work boosts the light-matter interaction at the nanoscale and could enable photodetectors, sensors, and photovoltaic devices in the future.

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Rational design of technologically important exotic perovskites is hampered by the insufficient geometrical descriptors and costly and extremely high-pressure synthesis, while the big-data driven compositional identification and precise prediction entangles full understanding of the possible polymorphs and complicated multidimensional calculations of the chemical and thermodynamic parameter space. Here we present a rapid systematic data-mining-driven approach to design exotic perovskites in a high-throughput and discovery speed of the A2BB’O6 family as exemplified in A3TeO6. The magnetoelectric polar magnet Co3TeO6, which is theoretically recognized and experimentally realized at 5 GPa from the six possible polymorphs, undergoes two magnetic transitions at 24 and 58 K and exhibits helical spin structure accompanied by magnetoelastic and magnetoelectric coupling. We expect the applied approach will accelerate the systematic and rapid discovery of new exotic perovskites in a high-throughput manner and can be extended to arbitrary applications in other families.

High-pressure solid-state synthesis advances boost discoveries of new materials and unusual phenomena but endures stringent recipe conditions, poor yield, and high cost. A methodological approach for accelerated and precisely high-pressure synthesis is therefore highly desired. Here, we take the exotic double-perovskite-related nonmagnetic Li2 B +4 B′+6O6 as an example to show the pipeline of data-mining, high-throughput calculations, experimental realization, and chemical interception of metastable phases. A total of 140 compounds in 7 polymorph categories were initially screened by the convex hull, which left ∼50% candidates in chemical space on the phase diagram of pressure-dependent polymorph evolution. Li2TiWO6 and Li2TiTeO6 were singled out for experimental testing according to the predicted map of crystal structure, function, and synthesis parameters. Computation on surface energy effect and interfacial chemical strain suggested that the as-made high-pressure R3-Li2TiTeO6 polymorph cannot be intercepted below a critical nanoscale but can be stabilized in heterojunction film on a selected compressive substrate at ambient pressure. The developed methodology is expected to accelerate the big-data-driven discovery of generic chemical formula-based new materials beyond perovskites by high-pressure synthesis and shed light on the large-scale stabilization of metastable phases under mild conditions.

Pressure-induced crossover from long-to-short-range order in [Pb(Zn 1/3 Nb 2/3 )O 3 ] 0.905 (PbTiO 3 ) 0.095 single crystal Using the first-principle calculations, we investigate in detail the structure instability resulting from softening of the polar zone-center phonon mode ͓ferroelectric ͑FE͒ instability͔ and nonpolar zone-boundary mode ͓antiferrodistortive ͑AFD͒ instability͔ in cubic BaZrO 3 ͑BZO͒ under hydrostatic pressure P from Ϫ20 to 90 GPa. The hydrostatic pressure enhances the AFD instability, while it suppresses and then enhances the FE instability. A sequence of FE→ cubic→ AFD → AFD/ FE phase transitions with increasing P is predicted. A careful examination of the pressure dependence of full phonon dispersions and interatomic force constants in real space reveals the microscopic key interactions in driving the transitions. With increasing pressure P, the drastically evolving short-range forces suppress the FE instability induced by the long-range dipole-dipole forces under low pressure, and enhance both the AFD and FE instability under high pressure. We investigate the dielectric properties of cubic BZO under hydrostatic pressure. The dielectric constant as a function of pressure shows a minimum contributed from the TO 1 mode with the lowest frequency. We argue that this pressure dependence of the dielectric constant mainly originates from fluctuations of the SR forces.