Molecular Hydride Superconductor BiH with up to 91 K at 170 GPa.

In pursuit of high- hydride superconductors, the molecular hydrides have attracted less attention because the hydrogen quasimolecules are usually inactive for superconductivity. Here, we report on the successful synthesis of a novel bismuth hydride superconductor 2/-BiH at pressures around 170-180 GPa. Its structure comprises bismuth atoms and elongated hydrogen molecules with a H-H bond length of 0.

Pressure-induced polymerization of 1,4-difluorobenzene towards fluorinated diamond nanothreads.

Pressure-induced polymerization (PIP) of aromatic molecules has emerged as an effective method for synthesizing various carbon-based materials. The selection of suitable functionalized molecular precursors is crucial for obtaining the desired structures and functions. In this work, 1,4-difluorobenzene (1,4-DFB) was selected as the building block for PIP.

Pressure aging: An effective process to liberate the power of high-pressure materials research.

High pressure can create extreme conditions that enable the formation of novel materials and the discovery of new phenomena. However, the ability to preserve the desirable characteristics of materials obtained under high pressure has remained an elusive challenge, as the pressure-induced changes are typically reversible, except for the pressure-induced chemical reactions such as polymerization of hydrocarbons. Here, we propose the concept of "pressure aging" (PA) that enables the permanent locking-in of high-pressure structures and their associated enhanced properties in functional materials.

n- to p-Type Conductivity Transition of LuN@C Due to Anisotropic Deformation of Fullerene and Pyramidalization of Endohedral Clusters.

The endohedral fullerene LuN@C was examined using in situ high-pressure measurements, which included electrical transport, Fourier-transform infrared spectroscopy, and Raman spectroscopy, in combination with theoretical calculations. LuN@C was found to undergo a reversible n- to p-type conversion at ∼8.9 GPa.

Rare-Metal-Free Ultrabroadband Near-Infrared Phosphors.

Trivalent chromium (Cr) is an attractive near-infrared (NIR) emitter, but its ultrabroadband NIR emission is limited to host crystals containing large amounts of rare-metal elements and usually suffers from low internal quantum efficiency (IQE) and poor thermal stability. Here, a class of high-performance, rare-metal-free ultrabroadband NIR phosphors, are reported by revealing that weak-field Cr centers featuring broadband NIR emission with near-unity IQEs are intrinsic, though in trace quantities, to Cr doped MgAlO spinel (MAS) and its derivatives well-known for their narrowband far-red emission. It is shown that such weak-field Cr centers stem from cation inversion ubiquitous in spinel compounds, and their quantity can be increased simply by superstoichiometric AlO/GaO.

Visible Light-Triggered Self-Welding Perovskite Solar Cells and Modules.

Flexible perovskite solar cells (F-PSCs) are highly promising for both stationary and mobile applications because of their advantageous features, including mechanical flexibility, their lightweight and thin nature, and cost-effectiveness. However, a number of drawbacks, such as mechanical instability, make their practical application difficult. Here, self-welding dynamic diselenide that is triggered by visible light into the structure of F-PSCs to improve their long-term stability by repairing cracks and defects in the absorber layer is incorporated.

Electronic perturbation of Cu nanowire surfaces with functionalized graphdiyne for enhanced CO reduction reaction.

Electronic perturbation of the surfaces of Cu catalysts is crucial for optimizing electrochemical CO reduction activity, yet still poses great challenges. Herein, nanostructured Cu nanowires (NW) with fine-tuned surface electronic structure are achieved via surface encapsulation with electron-withdrawing (-F) and -donating (-Me) group-functionalized graphdiynes (R-GDY, R = -F and -Me) and the resulting catalysts, denoted as R-GDY/Cu NW, display distinct CO reduction performances. electrochemical spectroscopy revealed that the *CO (a key intermediate of the CO reduction reaction) binding affinity and consequent *CO coverage positively correlate with the Cu surface oxidation state, leading to favorable C-C coupling on F-GDY/Cu NW over Me-GDY/Cu NW.

Unusual metallic state in superconducting A15-type LaH.

Hydride superconductors continue to fascinate the communities of condensed matter physics and material scientists because they host the promising near room-temperature superconductivity. Current research has concentrated on the new hydride superconductors with the enhancement of the superconducting transition temperature ( ). The multiple extreme conditions (high pressure/temperature and magnetic field) will introduce new insights into hydride superconductors.

Synthesis of NaWH and NaReH Ternary Hydrides at High Pressures.

The Na-W-H and Na-Re-H ternary systems were studied in a diamond anvil cell through X-ray diffraction and Raman spectroscopy, supported by density functional theory and molecular dynamics calculations. NaWH can be synthesized above 7.8 GPa and 1400 K, remaining stable between at least 0.

Synthesis and Stability of Biomolecules in C-H-O-N Fluids under Earth's Upper Mantle Conditions.

How life started on Earth is an unsolved mystery. There are various hypotheses for the location ranging from outer space to the seafloor, subseafloor, or potentially deeper. Here, we applied extensive ab initio molecular dynamics simulations to study chemical reactions between NH, HO, H, and CO at pressures () and temperatures () approximating the conditions of Earth's upper mantle (i.

Enhanced UV Light Responsivity in <110>-Oriented 2D Perovskites Realized by Pressure-Induced Ultrafast Exciton Transport.

Two-dimensional (2D) <100>-oriented perovskites exhibit superior optoelectronic properties, offering significant potential in photovoltaic, light-emitting, and photodetection applications. Nevertheless, their enlarged interlayer spacing restricts longitudinal carrier transport, thereby limiting its potential applications. While <110>-oriented 2D perovskites provide a prospective solution with their compact interlayer spacing, their inherent structure, characterized by octahedra tilting, indirectly hinders carrier transport due to the generation of self-trapped excitons (STEs) caused by strong electron-phonon coupling.

Lateral Heterostructures Fabricated via Artificial Pressure Gradient.

Hydrostatic conditions are generally pursued in high-pressure research, maintained to prevent the intrinsic pressure gradient on the culets of diamond anvil cells (DACs) from introducing heterogeneity to the structure and physical properties of the regulated materials. Here, a pioneering route to fabricate lateral heterostructures is proposed via artificial pressure gradients intentionally designed in DACs. Under the tailored pressure gradients, different structural phases emerge in distinct parts of the material, resulting in the formation of heterostructures.

The Transformation Mechanism of Graphite to Hexagonal Diamond under Shock Conditions.

The formation of a hexagonal diamond represents one of the most intriguing questions in materials science. Under shock conditions, the graphite basal plane tends to slide and pucker to form diamond. However, how the shock strength determines the phase selectivity remains unclear.

In situ fabrication of NiS/CuS heterojunction on nickel foam as a highly efficient and durable electrocatalyst for overall water splitting.

The development of cost-efficient bifunctional electrocatalysts is significant for overall water splitting. Herein, we report the in situ fabrication of heterogeneous NF/NiS/CuS-X (where X refers to Cu concentrations of 50, 75, and 100 mM) on nickel foam (NF) using an electrodeposition-hydrothermal method. The in situ electrodeposited metallic Cu layers on the NF conferred higher stability to the resulting bimetallic sulfide of NiS/CuS.

Defect Structure, Oxygen Ion Conduction, and Conducting Mechanism in Ruddlesden-Popper SrZrMO (M = Ga, Y, In).

Ruddlesden-Popper (RP)-structured materials based on transition metals with a variable valence, such as Fe, Mn, Ni, and so on, have been well documented for their potential of being used as electrodes in solid-oxide fuel cells. However, RP materials with pure or dominant ionic conduction are rare. Here, a series of Zr-based RP materials SrZrMO (M = Ga, Y, In) with electrical conductivity as high as 3.

Alkali Metals Activated High Entropy Double Perovskites for Boosted Hydrogen Evolution Reaction.

An efficient and facile water dissociation process plays a crucial role in enhancing the activity of alkaline hydrogen evolution reaction (HER). Considering the intricate influence between interfacial water and intermediates in typical catalytic systems, meticulously engineered catalysts should be developed by modulating electron configurations and optimizing surface chemical bonds. Here, a high-entropy double perovskite (HEDP) electrocatalyst La(CoNiMgZnNaLi)RuO, achieving a reduced overpotential of 40.

Brightening triplet excitons enable high-performance white-light emission in organic small molecules via integrating n-π*/π-π* transitions.

Luminescent materials that simultaneously embody bright singlet and triplet excitons hold great potential in optoelectronics, signage, and information encryption. However, achieving high-performance white-light emission is severely hampered by their inherent unbalanced contribution of fluorescence and phosphorescence. Herein, we address this challenge by pressure treatment engineering via the hydrogen bonding cooperativity effect to realize the mixture of n-π*/π-π* transitions, where the triplet state emission was boosted from 7% to 40% in isophthalic acid (IPA).

Pressure-Sensitive Multiple Superconducting Phases and Their Structural Origin in Van der Waals HfS_{2} Up to 160 GPa.

Superconductivity has been observed in many insulating transition metal dichalcogenides (TMDCs) under pressure. However, the origin of superconductivity remains elusive due to the lack of studies on their structures at low temperatures. Here, we report the observation of a high-T_{c} superconducting state (SC-I phase) coexisting with other superconducting states in a compressed 1T-HfS_{2} crystal up to approximately 160 GPa.

Vertical Barrier Heterostructures for Reliable and High-Performance Self-Powered Infrared Detection.

With their fascinating properties, emerging two-dimensional (2D) materials offer innovative ways to prepare high-performance infrared (IR) detectors. However, the current performance of 2D IR photodetectors is still below the requirements for practical application owing to the severe interfacial recombination, sharply raised contact resistance, and deteriorated metal conductivity at nanoscale. Here, we introduce a vertical barrier heterojunction with a structure of PtSe/GaAs that combines the excellent optoelectronic properties of transition metal sulfides with topological semi-metals, which allows for an adjustable bandgap and high carrier mobility.

Lightweight single-phase Al-based complex concentrated alloy with high specific strength.

Developing light yet strong aluminum (Al)-based alloys has been attracting unremitting efforts due to the soaring demand for energy-efficient structural materials. However, this endeavor is impeded by the limited solubility of other lighter components in Al. Here, we propose to surmount this challenge by converting multiple brittle phases into a ductile solid solution in Al-based complex concentrated alloys (CCA) by applying high pressure and temperature.