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Although high-transition-temperature (high- T c ) superconductivity in cuprates has been known for more than three decades, the underlying mechanism remains unknown 1 – 4 . Cuprates are the only unconventional superconductors that exhibit bulk superconductivity with T c above the liquid-nitrogen boiling temperature of 77 K. Here we observe that high-pressure resistance and mutual inductive magnetic susceptibility measurements showed signatures of superconductivity in single crystals of La 3 Ni 2 O 7 with maximum T c of 80 K at pressures between 14.0 GPa and 43.5 GPa. The superconducting phase under high pressure has an orthorhombic structure of Fmmm space group with the 3 d x 2 − y 2 and 3 d z 2 orbitals of Ni cations strongly mixing with oxygen 2 p orbitals. Our density functional theory calculations indicate that the superconductivity emerges coincidently with the metallization of the σ-bonding bands under the Fermi level, consisting of the 3 d z 2 orbitals with the apical oxygen ions connecting the Ni–O bilayers. Thus, our discoveries provide not only important clues for the high- T c superconductivity in this Ruddlesden–Popper double-layered perovskite nickelates but also a previously unknown family of compounds to investigate the high- T c superconductivity mechanism. Signatures of superconductivity in single crystals of La 3 Ni 2 O 7 were observed at a maximum transition temperature of 80  K at pressures between 14.0  GPa and 43.5  GPa.

Cell cracking of photovoltaic (PV) modules occurs frequently during production, packaging, transportation, installation, and operation processes. In order to reveal the quantitative relationship between cell cracking and I-V characteristics, we explore the modeling of PV modules with cracked cells. Firstly, the impact of cracks on the electrical interconnection is analyzed. Cracks crossing the metallization of the silicon cell may result in extra resistance and the inactive part, making this cell partially interconnected. Secondly, the sub-cell model for a partially interconnected cell and its equivalent circuit for electroluminescence (EL) detection are proposed. Next, PV modules with cracked cells are modeled based on the electrical interconnection. The PV module is collected from the manufacturer to compare its EL image and I-V characteristics before and after artificial mechanical destruction. The defective PV module operating for several years is also collected. Experimental results verify the effectiveness of the proposed model.

The oxidative dehydrogenation of propane using CO 2 (CO 2 -ODP) is a promising technique for high-yield propylene production and CO 2 utilization. The development of a highly efficient catalyst for CO 2 -ODP is of great interest and benefit to the chemical industry as well as net zero emissions. Here, we report a unique catalyst material and design concept based on high-entropy intermetallics for this challenging chemistry. A senary (PtCoNi)(SnInGa) catalyst supported on CeO 2 with a PtSn intermetallic structure exhibits a considerably higher catalytic activity, C 3 H 6 selectivity, long-term stability, and CO 2 utilization efficiency at 600 °C than previously reported. Multi-metallization of the Pt and Sn sites by Co/Ni and In/Ga, respectively, greatly enhances propylene selectivity, CO 2 activation ability, thermal stability, and regenerable ability. The results obtained in this study can promote carbon-neutralization of industrial processes for light alkane conversion. The oxidative dehydrogenation of propane using CO 2 is a promising technique for high-yield propylene production and CO 2 utilization. Here the authors report a unique catalyst material and design concept based on high-entropy intermetallics for this challenging chemistry.

One of the long-standing challenges in experimental physics is the observation of room-temperature superconductivity . Recently, high-temperature conventional superconductivity in hydrogen-rich materials has been reported in several systems under high pressure . An  important discovery leading to room-temperature superconductivity is the pressure-driven disproportionation of hydrogen sulfide (H S) to H S, with a confirmed transition temperature of 203 kelvin at 155 gigapascals . Both H S and CH readily mix with hydrogen to form guest-host structures at lower pressures , and are of  comparable size at 4 gigapascals. By introducing methane at low pressures into the H S + H precursor mixture for H S, molecular exchange is allowed within a large assemblage of van der Waals solids that are hydrogen-rich with H inclusions; these guest-host structures become the building blocks of superconducting compounds at extreme conditions. Here we report superconductivity in a photochemically transformed carbonaceous sulfur hydride system, starting from elemental precursors, with a maximum superconducting transition temperature of 287.7 ± 1.2 kelvin (about 15 degrees Celsius) achieved at 267 ± 10 gigapascals. The superconducting state is observed over a broad pressure range in the diamond anvil cell, from 140 to 275 gigapascals, with a sharp upturn in transition temperature above 220 gigapascals. Superconductivity is established by the observation of zero resistance, a magnetic susceptibility of up to 190 gigapascals, and reduction of the transition temperature under an external magnetic field of up to 9 tesla, with an upper critical magnetic field of about 62 tesla according to the Ginzburg-Landau model at zero temperature. The light, quantum nature of hydrogen limits the structural and stoichiometric determination of the system by X-ray scattering techniques, but Raman spectroscopy is used to probe the chemical and structural transformations before metallization. The introduction of chemical tuning within our ternary system could enable the preservation of the properties of room-temperature superconductivity at lower pressures.

Producing metallic hydrogen has been a great challenge in condensed matter physics. Metallic hydrogen may be a room-temperature superconductor and metastable when the pressure is released and could have an important impact on energy and rocketry. We have studied solid molecular hydrogen under pressure at low temperatures. At a pressure of 495 gigapascals, hydrogen becomes metallic, with reflectivity as high as 0.91. We fit the reflectance using a Drude free-electron model to determine the plasma frequency of 32.5 ± 2.1 electron volts at a temperature of 5.5 kelvin, with a corresponding electron carrier density of 7.7 ± 1.1 × 1023 particles per cubic centimeter, which is consistent with theoretical estimates of the atomic density. The properties are those of an atomic metal. We have produced the Wigner-Huntington dissociative transition to atomic metallic hydrogen in the laboratory.

According to relevant statistics, an aircraft will encounter lightning every 3000 hours on average. According to relevant research, the vast majority of aircraft encounter lightning during falling or climbing. For lightning protection of composite radome, there are usually measures such as metallization treatment on the surface, the layout of lightning protection diversion strips, etc., to avoid lightning on the radome by guiding the flash current.

Eighty years ago, it was proposed that solid hydrogen would become metallic at sufficiently high density. Despite numerous investigations, this transition has not yet been experimentally observed. More recently, there has been much interest in the analog of this predicted metallic transition in the dense liquid, due to its relevance to planetary science. Here, we show direct observation of an abrupt insulator-to-metal transition in dense liquid deuterium. Experimental determination of the location of this transition provides a much-needed benchmark for theory and may constrain the region of hydrogen-helium immiscibility and the boundary-layer pressure in standard models of the internal structure of gas-giant planets.

Space heating accounts for the largest energy end-use of buildings that imposes significant burden on the society. The energy wasted for heating the empty space of the entire building can be saved by passively heating the immediate environment around the human body. Here, we demonstrate a nanophotonic structure textile with tailored infrared (IR) property for passive personal heating using nanoporous metallized polyethylene. By constructing an IR-reflective layer on an IR-transparent layer with embedded nanopores, the nanoporous metallized polyethylene textile achieves a minimal IR emissivity (10.1%) on the outer surface that effectively suppresses heat radiation loss without sacrificing wearing comfort. This enables 7.1 °C decrease of the set-point compared to normal textile, greatly outperforming other radiative heating textiles by more than 3 °C. This large set-point expansion can save more than 35% of building heating energy in a cost-effective way, and ultimately contribute to the relief of global energy and climate issues. Energy wasted for heating the empty space of the entire building can be saved by passively heating the immediate environment around the human body. Here, the authors show a nanophotonic structure textile with tailored infrared property for passive personal heating using nanoporous metallized polyethylene.

The possibility of high, room-temperature superconductivity was predicted for metallic hydrogen in the 1960s. However, metallization and superconductivity of hydrogen are yet to be unambiguously demonstrated and may require pressures as high as 5 million atmospheres. Rare earth based “superhydrides”, such as LaH 10 , can be considered as a close approximation of metallic hydrogen even though they form at moderately lower pressures. In superhydrides the predominance of H-H metallic bonds and high superconducting transition temperatures bear the hallmarks of metallic hydrogen. Still, experimental studies revealing the key factors controlling their superconductivity are scarce. Here, we report the pressure and magnetic field dependence of the superconducting order observed in LaH 10 . We determine that the high-symmetry high-temperature superconducting Fm-3m phase of LaH 10 can be stabilized at substantially lower pressures than previously thought. We find a remarkable correlation between superconductivity and a structural instability indicating that lattice vibrations, responsible for the monoclinic structural distortions in LaH 10 , strongly affect the superconducting coupling. The experimental studies to understand the superconductivity of superhydrides remain scarce. Here, the authors report pressure and magnetic field dependence of superconductivity in LaH 10 , and indicate lattice vibrations strongly affect superconducting coupling.