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Additive engineering, with its excellent ability to passivate bulk or surface perovskite defects, has become a common strategy to improve the performance and stability of perovskite solar cells (PVSCs). Among the various additives reported so far, ammonium salts are considered an important branch. It is worth noting that although both ammonium‐based additives (R‐NH3+) and amine‐based additives (R‐NH2) are derivatives of ammonia (NH3), the functions of the two can be easily confused due to their structural similarities. Moreover, there is no comprehensive comparative analysis of them in the literature. Here, the differences between phenethylammonium iodide (PEA+) and phenethylamine (PEA) additives are revealed experimentally and theoretically. The results clearly show that PEA outperforms PEA+ in terms of device performance and stability based on the following three factors: i) PEA's defect passivation capability is superior to that of PEA+; ii) PEA has better hydrophobicity to hinder water ingress; and iii) PEA completely improves the stability of PVSCs by enhancing thermal stability and inhibiting iodide migration in perovskite more effectively than PEA+. As a result, the power conversion efficiency (PCE) of the inverted methylammonium triiodide (MAPbI3) device using PEA increases by ≈15% to over 21%. More importantly, this device exhibits greater ability to prevent water invasion, thermal‐induce degradation, and inhibit iodide ion migration, resulting in better long‐term stability. [ABSTRACT FROM AUTHOR]

Lately, carbazole‐based self‐assembled monolayers (SAMs) are widely employed as effective hole‐selective layers (HSLs) in inverted perovskite solar cells (PSCs). Nevertheless, these SAMs tend to aggregate in solvents due to their amphiphilic nature, hindering the formation of a monolayer on the ITO substrate and impeding effective passivation of deep defects in the perovskites. In this study, a series of new SAMs including DPA‐B‐PY, CBZ‐B‐PY, POZ‐B‐PY, POZ‐PY, POZ‐T‐PY, and POZ‐BT‐PY are synthesized, which are employed as interfacial repairers and coated atop CNph SAM to form a robust CNph SAM@pseudo‐planar monolayer as HSL in efficient inverted PSCs. The CNph SAM@pseudo‐planar monolayer strategy enables a well‐aligned interface with perovskites, synergistically promoting perovskite crystal growth, improving charge extraction/transport, and minimizing nonradiative interfacial recombination loss. As a result, the POZ‐BT‐PY‐modified PSC realizes an impressively enhanced solar efficiency of up to 24.45% together with a fill factor of 82.63%. Furthermore, a wide bandgap PSC achieving over 19% efficiency. Upon treatment with the CNph SAM@pseudo‐planar monolayer, also demonstrates a non‐fullerene organic photovoltaics (OPVs) based on the PM6:BTP‐eC9 blend, which achieves an efficiency of 17.07%. Importantly, these modified PSCs and OPVs all show remarkably improved stability under various testing conditions compared to their control counterparts. [ABSTRACT FROM AUTHOR]

We fabricate lithium tin-based oxide Li2SnO3 on carbon cloth from a gel-state precursor containing LiCl and SnCl2·2H2O using a nitrogen atmospheric-pressure plasma jet (APPJ). APPJ treatment provides both a high-temperature environment for the conversion of precursor into Li2SnO3 and nitrogen plasma reactive species for electrode surface modification. Here, the best electrochemical performance for the Li2SnO3 Li-ion hybrid supercapacitors (Li–HSCs) is achieved with 480 s of APPJ processing. The areal capacity of the 480 s APPJ-processed Li2SnO3 Li–HSCs reached 46.113 mC/cm2. The results indicate that APPJ is an effective tool for the rapid conversion processing of Li2SnO3 electrodes for Li–HSCs. [ABSTRACT FROM AUTHOR]

We investigated the effects of resistance exercise under hypoxia on postexercise hemodynamics in eight healthy young males. The subjects belonged to a track & field club (sprinters, hurdlers, and long jumpers) and engage in regular physical training (1-2 h per day, 3-5 days per week). Each participant performed eight sets of bilateral leg squats with a one-minute interval under normoxia (room air) and hypoxia (13 % FiO2). During a 60-minute recovery, we set normoxic condition either after normoxic or hypoxic exercise. These two experimental protocols (normoxia and hypoxia) were performed in a random order with a one-week washout period. The leg squat exercise consists of 50 % 1-RM (14 repetitions) × 5 sets and 50% 1-RM (repetitions max; 7 repetitions) × 3 sets. The resting period between each set was 1 min, and a total of 91 repetitions were performed. Blood pressure, heart rate (HR), and several biomarkers were measured pre- and postexercise. The mean arterial pressure (MAP) significantly decreased after exercise compared to the pre-exercise values under both conditions (P < 0.05). The MAP at 20 and 30 min of recovery in hypoxia was significantly lower than in normoxia (P < 0.05, respectively). The antidiuretic hormone significantly increased after 60 min of recovery in both conditions; moreover, the values in hypoxia were significantly higher than those in normoxia (P < 0.05). The delta changes in MAP from baseline (pre-exercise) were significantly related to changes in HR from baseline in normoxia (r = 0.560, P < 0.001) but not in hypoxia. These results suggest that the hypoxic condition elicits greater hypotension after resistance exercise in comparison to normoxia. Moreover, the underlying mechanisms for the attenuation of hypotension after resistance exercise may differ between normoxia and hypoxia.

Inverted perovskite solar cells (PSCs) mainly adopt polytriarylamine (PTAA) for the hole transport material (HTM), which usually brings about inferior interfacial contact owing to their hydrophobicity, high‐lying highest occupied molecular orbital energy level, and deficiency of passivation groups. Herein, a series of donor–π–acceptor (D–π–A) type small molecules is demonstrated based on 2,2′:6′,2″‐terpyridine (TPy) as the acceptor moiety, benzene ring as the π‐linker, and incorporating various donors to act as HTMs. These TPy‐based molecules coated atop PTAA manipulate the energy level and surface wettability, but the incorporation of the phenoxazine (POZ) donor can be prominent for enhancing charge transport and defect passivation, thereby simultaneously addressing the above‐mentioned issues. The highest power conversion efficiency of 22.36% can be achieved with an open‐circuit voltage (VOC) of 1.15 V, a short‐circuit current density (JSC) of 23.96 mA cm−2, and a fill factor (FF) of 81.16% for the optimized POZ‐TPy‐modified device. Moreover, the power PCE of a large POZ‐TPy‐modified device (1.96 cm2) can still reach more than 21%. These results are among one of the highest efficiencies for inverted PSCs, indicating the enormous potential of POZ‐TPy HTM in future perovskite applications. [ABSTRACT FROM AUTHOR]

Pastes containing reduced graphene oxide (rGO) and LiCl-Mn(NO3)2·4H2O are screen-printed on a carbon cloth substrate and then calcined using a nitrogen atmospheric-pressure plasma jet (APPJ) for conversion into rGO-LiMnOx nanocomposites. The APPJ processing time is within 300 s. RGO-LiMnOx on carbon cloth is used to sandwich H2SO4, LiCl, or Li2SO4 gel electrolytes to form hybrid supercapacitors (HSCs). The areal capacitance, energy density, and cycling stability of the HSCs are evaluated using electrochemical measurement. The HSC utilizing the Li2SO4 gel electrolyte exhibits enhanced electrode–electrolyte interface reactions and increased effective surface area due to its high pseudocapacitance (PC) ratio and lithium ion migration rate. As a result, it demonstrates the highest areal capacitance and energy density. The coupling of charges generated by embedded lithium ions with the electric double-layer capacitance (EDLC) further contributed to the significant overall capacitance enhancement. Conversely, the HSC with the H2SO4 gel electrolyte exhibits better cycling stability. Our findings shed light on the interplay between gel electrolytes and electrode materials, offering insights into the design and optimization of high-performance HSCs. [ABSTRACT FROM AUTHOR]

Since the discovery of graphene, 2D materials are establishing a rapidly growing and promising field, with great potential for diverse applications given their excellent conductivity and high transparency. In particular, graphene can isolate external chemical reactions when applied to back-end-of-line (BEOL) interconnect metals, thereby preventing the oxidation of the interconnect metals. In addition, it can improve the conductivity and breakdown current density of interconnects. However, the thermal budget remains an important problem in BEOL interconnects. We demonstrate an advanced graphene deposition method using an in-house plasma plasma-enhanced chemical vapor deposition system, which offers low thermal budget and high stability. We also optimize carbon precursors to improve the quality of graphene on Ru and Co thin films. We show the improvement of electrical conductivity, electromigration lifetime, and maximum breakdown current density after capping Ru and Co interconnects with graphene. The electromigration lifetimes of the Ru and Co interconnects increase by 4 and 4.5 times, respectively, and their maximum breakdown current density increases by 17.6 and 10.6%, respectively. The results show that capping with graphene has a high potential in BEOL applications. [ABSTRACT FROM AUTHOR]

In recent years, many reports have demonstrated the high potential for multilayer graphene in semiconductor fabrication. As interconnects within semiconductors or electrodes for two-dimensional transistors, the preparation of large-area multilayer graphene is becoming increasingly important. Herein, we report a method for growing large-area multilayer graphene, which can achieve rapid heating and cooling. With the use of a high carbon concentration source, the preparation of multilayer graphene can be completed in a few seconds. This manufacturing method has the advantage of producing graphene with high quality, uniformity, and electrical conductivity. In commercial applications, this technology has great potential for the mass production and rapid fabrication of multilayer graphene. In addition, we found that the multilayer graphene produced by this method had cobalt atoms doped into the multilayer graphene during the process, resulting in its low resistivity. Combined with our intercalation technology, intercalated FeCl3 in the graphene interlayer can reduce the resistivity of graphene to 3.55 μΩ cm, which is very close to the resistivity of copper bulk. This result makes multilayer graphene more promising for various applications. [ABSTRACT FROM AUTHOR]

The correlation between the electrodes and the properties of the BiI3 device is systematically investigated. The X‐ray and UV photoemission spectroscopies are carried out to study the chemical state and electronic structure of the metal/BiI3 interfaces formed by the in‐situ deposition of BiI3 on the metal. This revealed the upward diffusion of Ag and the self‐formation of a conductive filament; the latter is further confirmed via tunneling electron microscopy. By coating the Au substrate with Ag layers of various thicknesses as a buffer layer, the morphology, surface roughness, chemical states, and quantity of the filament in the BiI3 layer can be manipulated. The device with the structure of Au/10 nm Ag/BiI3/Au demonstrated an ultrahigh on/off ratio of 109, good retention of 104 s, and multistate data storage. This study provides not only a fundamental insight into the interaction of BiI3 with metal, which will be helpful to design resistive switching devices and optoelectronics based on BiI3 material, but also a facile method to control the quantity of conductive filament in the BiI3 layer. [ABSTRACT FROM AUTHOR]