Room-temperature superconductivity has been a long-held dream and an area of intensive research. The discovery of H3S and LaH10 under high pressure, with superconducting critical temperatures (Tc) above 200 K, sparked a race to find room temperature superconductors in compressed superhydrides. In recent groundbreaking work, room-temperature superconductivity of 288 K was achieved in carbonaceous sulfur hydride at 267 GPa. Here, we describe the important attempts of hydrides in the process of achieving room temperature superconductivity in decades, summarize the main characteristics of high-temperature hydrogen-based superconductors, such as hydrogen structural motifs, bonding features, electronic structure as well as electron-phonon coupling etc. This work aims to provide an up-to-date summary of several type hydrogen-based superconductors based on the hydrogen structural motifs, including covalent superhydrides, clathrate superhydrides, layered superhydrides, and hydrides containing isolated H atom, H2 and H3 molecular units.

No abstract

Post‐combustion flue gas (mainly containing 5–40% CO2 balanced by N2) accounts for about 60% global CO2 emission. Rational conversion of flue gas into value‐added chemicals is still a formidable challenge. Herein, this work reports a β‐Bi2O3‐derived bismuth (OD‐Bi) catalyst with surface coordinated oxygen for efficient electroreduction of pure CO2, N2, and flue gas. During pure CO2 electroreduction, the maximum Faradaic efficiency (FE) of formate reaches 98.0% and stays above 90% in a broad potential of 600 mV with a long‐term stability of 50 h. Additionally, OD‐Bi achieves an ammonia (NH3) FE of 18.53% and yield rate of 11.5 µg h−1 mgcat−1 in pure N2 atmosphere. Noticeably, in simulated flue gas (15% CO2 balanced by N2 with trace impurities), a maximum formate FE of 97.3% is delivered within a flow cell, meanwhile above 90% formate FEs are obtained in a wide potential range of 700 mV. In‐situ Raman combined with theory calculations reveals that the surface coordinated oxygen species in OD‐Bi can drastically activate CO2 and N2 molecules by selectively favors the adsorption of *OCHO and *NNH intermediates, respectively. This work provides a surface oxygen modulation strategy to develop efficient bismuth‐based electrocatalysts for directly reducing commercially relevant flue gas into valuable chemicals.

Compressed hydrogen-rich compounds have received extensive attention as appealing contenders for superconductors. Here, we found several stable hydrides YZrH6, YZrH8, YZr3H16, YZrH18 and a series of metastable clathrate hexahydrides in...

No abstract