Rubidium Incorporation Research Articles

ZnSnO3 micro-polyhedrons with oxygen defects derived from rubidium incorporation for enhanced ethanol detection

Detecting ethanol in ambient air is of great significance in protection of ecological environment, human health and social economy. Herein, a strategy is adopted to substantially improve the gas sensing performance of the ZnSnO3 micro-polyhedrons through rubidium (Rb) doping. In this study, a series of ZnSnO3 micro-polyhedrons with different amounts of Rb doping were successfully synthesized through a typical hydrothermal procedure and air sintering. The sensor based on 2 mol% Rb-doped ZnSnO3 exhibits high response value (108) and rapid response/recover speed (20/8 s) to 100 ppm ethanol at 260 °C, as well as outstanding repeatability and stability. Combining theoretical calculations and various characterization techniques, the improved sensing property of the 2 mol% Rb-doped ZnSnO3 to ethanol gas can be ascribed to the large specific surface area and the abundant surface defects induced by Rb incorporation. We believe that this study opens up a new perspective for developing efficient and high-performance ethanol gas sensor.

Effect of rubidium incorporation on the structural, electronic and properties of MAPbI3

The structural stability, electronic and optical properties of Rb-incorporated methylammonium lead halide perovskite (MAPbI3) were investigated by first-principles calculations. A high fraction of Rb+ incorporation can degrade the phase stability of MAPbI3. Moreover, the band gap of Rb-doped MAPbI3 exhibits slightly blueshifted. The optical absorption of Rb-doped MAPbI3 is almost the same with that of the undoped MAPbI3, which can be attributed to the close band gaps of them. Our work can agree well with existing experimental results. Our calculated results can provide a basic insight into the mixed-cation halide perovskites for optoelectronic applications.

Effect of rubidium incorporation on the optical properties and intermixing in Mo/Si multilayer mirrors for EUV lithography applications

High reflectivity and long-term stability in multilayer mirrors (MLMs) are crucial for extreme ultraviolet (EUV) photolithography. The conventional base stack to reflect 13.5 nm light is a Mo/Si multilayer, which offers a maximum theoretical reflectivity of 75%. In practice, however, the efficiency of the mirror is strongly affected by intermixing between Mo and Si. Diffusion barriers have therefore been adopted, which nevertheless do not provide a perfect solution. In this work, we propose to suppress intermixing in Mo/Si MLMs by substituting the pure Si with a Si compound that can ensure higher thermodynamic stability, while simultaneously providing comparably high EUV theoretical reflectivity, with the net effect of increasing both reflectivity and lifetime. Our theoretical calculations show that rubidium silicide is the most promising material for this purpose. We estimate the optical and thermodynamic properties for each phase of rubidium silicide, and we show that Mo/Rb12Si17 provides the highest theoretical reflectivity, while Mo/RbSi is the most thermodynamically stable. The suppression of intermixing in Mo/RbSi MLMs should lead to a maximum reflectivity at least 2% higher than the best Mo/Si MLMs, integrated with diffusion barriers. The proposed Mo/RbSi MLM solution has the potential to increase the total EUV lithography throughput by ~50%.

Improving the phase stability of inorganic lead halide perovskites through K/Rb doping

All-inorganic perovskites have gained considerable significance. Despite their superior thermal robustness, poor phase stability has rendered inorganic perovskites adverse. Herein, on the basis of first-principles calculations, we find that the incorporation of rubidium (Rb) and potassium (K) in an appropriate ratio will stabilize CsPbI2Br perovskites considerably, in which the cooperative interactions between Rb/K, I and Br play an important role. Besides, it is verified that 2D orthorhombic CsPbI3 with a thickness of ∼1 nm exhibits outstanding stability, even exceeding the non-perovskite, yellow structure and has a suitable band gap for solar cell applications.

Rubidium as an Alternative Cation for Efficient Perovskite Light-Emitting Diodes.

Incorporation of rubidium (Rb) into mixed lead halide perovskites has recently achieved record power conversion efficiency and excellent stability in perovskite solar cells. Inspired by these tremendous advances in photovoltaics, this study demonstrates the impact of Rb incorporation into MAPbBr3-based light emitters. Rb partially substitutes MA (methyl ammonium), resulting in a mixed cation perovskite with the formula MA(1- x)Rb xPbBr3. Pure MAPbBr3 crystallizes into a polycrystalline layer with highly defective sub-micrometer grains. However, the addition of a small amount of Rb forms MA(1- x)Rb xPbBr3 nanocrystals (10 nm) embedded in an amorphous matrix of MA/Rb Br. These nanocrystals grow into defect-free sub-micrometer-sized crystallites with further addition of Rb, resulting in a 3-fold increase in exciton lifetime when the molar ratio of MABr/RbBr is 1:1. A thin film fabricated with a 1:1 molar ratio of MABr/RbBr showed the best electroluminescent properties with a current efficiency (CE) of 9.45 cd/A and a luminance of 7694 cd/m2. These values of CE and luminance are, respectively, 19 and 10 times larger than those achieved by pure MAPbBr3 devices (0.5 cd/A and 790 cd/m2). We believe this work provides important information on the future compositional optimization of Rb+-based mixed cation perovskites for obtaining high-performance light-emitting diodes.

Rubidium Doping for Enhanced Performance of Highly Efficient Formamidinium-Based Perovskite Light-Emitting Diodes.

Organometal halide perovskites (OHPs) have become the most promising optoelectronic material in the past few years with a myriad of applications in the photovoltaic, light-emitting, and laser fields. However, for light-emitting applications, the low photoluminescence quantum yield (PLQY) of OHP film is critical to hinder the efficiency improvement of OHP-film-based light-emitting diodes (PeLEDs). Herein, we study the effects of rubidium incorporation on the crystal growth, structure, and photoelectric and optical properties of formamidinium-lead-bromide-based (FAPbBr3-based) perovskite films and light-emission performance of PeLEDs. It is found that rubidium incorporation can significantly enhance the PLQY of FAPbBr3 film by suppressing the trap density and thus improve the withstand voltage as well as the performance of PeLEDs. When FAPbBr3 film with optimal Rb doping ratio is employed as the light emitter of PeLEDs, the maximum luminance and current efficiency is enhanced by ∼10-fold and ∼5-fold to 66 353 cd/m2 and 24.22 cd/A compared to the controlled device, respectively, the record performance based on FAPbBr3 PeLEDs so far. The enhanced performance can be chiefly attributed to the increase of PLQY and decrease of trap defect density of perovskite film with rubidium incorporation. Our research is expected to stimulate the development of OHPs for the next-generation lighting and display fields.

Low‐Bandgap Methylammonium‐Rubidium Cation Sn‐Rich Perovskites for Efficient Ultraviolet–Visible–Near Infrared Photodetectors

AbstractSolution‐processed and low‐temperature Sn‐rich perovskites show their low bandgap of about 1.2 eV, enabling potential applications in next‐generation cost‐effective ultraviolet (UV)–visible (vis)–near infrared (NIR) photodetection. Particularly, the crystallization (crystallinity and orientation) and film (smooth and dense film) properties of Sn‐rich perovskites are critical for efficient photodetectors, but are limitedly studied. Here, controllable crystallization for growing high‐quality films with the improvements of increased crystallinity and strengthened preferred orientation through a introducing rubidium cation into the methylammonium Sn‐Pb perovskite system (65% Sn) is achieved. Fundamentally, the theoretical results show that rubidium incorporation causes lower surface energy of (110) plane, facilitating growth in the dominating plane and suppressing growth of other competing planes. Consequently, the methylammonium‐rubidium Sn‐Pb perovskite photodetectors simultaneously achieve larger photocurrent and lower noise current. Finally, highly efficient UV–vis–NIR (300–1100 nm) photodetectors with record‐high linear dynamic range of 110 and 3 dB cut‐off frequency reaching 1 MHz are demonstrated. This work contributes to enriching the cation selection in Sn‐Pb perovskite systems and offering a promising candidate for low‐cost UV–vis–NIR photodetection.

Effect of Rubidium Incorporation on the Structural, Electrical, and Photovoltaic Properties of Methylammonium Lead Iodide-Based Perovskite Solar Cells

We report the electrical properties of rubidium-incorporated methylammonium lead iodide ((RbxMA1-x)PbI3) films and the photovoltaic performance of (RbxMA1-x)PbI3 film-based p-i-n-type perovskite solar cells (PSCs). The incorporation of a small amount of Rb+ (x = 0.05) increases both the open circuit voltage (Voc) and the short circuit photocurrent density (Jsc) of the PSCs, leading to an improved power conversion efficiency (PCE). However, a high fraction of Rb+ incorporation (x = 0.1 and 0.2) decreases the Jsc and thus the PCE, which is attributed to the phase segregation of the single tetragonal perovskite phase to a MA-rich tetragonal perovskite phase and a RbPbI3 orthorhombic phase at high Rb fractions. Conductive atomic force microscopic and admittance spectroscopic analyses reveal that the single-phase (Rb0.05MA0.95)PbI3 film has a high electrical conductivity because of a reduced deep-level trap density. We also found that Rb substitution enhances the diode characteristics of the PSC, as evidenced by the reduced reverse saturation current (J0). The optimized (RbxMA1-x)PbI3 PSCs exhibited a PCE of 18.8% with negligible hysteresis in the photocurrent-voltage curve. The results from this work enhance the understanding of the effect of Rb incorporation into organic-inorganic hybrid halide perovskites and enable the exploration of Rb-incorporated mixed perovskites for various applications, such as solar cells, photodetectors, and light-emitting diodes.

Murine lung injury caused by Leptospira interrogans glycolipoprotein, a specific Na/K-ATPase inhibitor.

BackgroundLeptospiral glycolipoprotein (GLP) is a potent and specific Na/K-ATPase inhibitor. Severe pulmonary form of leptospirosis is characterized by edema, inflammation and intra-alveolar hemorrhage having a dismal prognosis. Resolution of edema and inflammation determines the outcome of lung injury. Na/K-ATPase activity is responsible for edema clearance. This enzyme works as a cell receptor that triggers activation of mitogen-activated protein kinase (MAPK) intracellular signaling pathway. Therefore, injection of GLP into lungs induces injury by triggering inflammation.MethodsWe injected GLP and ouabain, into mice lungs and compared their effects. Bronchoalveolar lavage fluid (BALF) was collected for cell and lipid body counting and measurement of protein and lipid mediators (PGE2 and LTB4). The levels of the IL-6, TNFα, IL-1B and MIP-1α were also quantified. Lung images illustrate the injury and whole-body plethysmography was performed to assay lung function. We used Toll-like receptor 4 (TLR4) knockout mice to evaluate leptospiral GLP-induced lung injury. Na/K-ATPase activity was determined in lung cells by nonradioactive rubidium incorporation. We analyzed MAPK p38 activation in lung and in epithelial and endothelial cells.ResultsLeptospiral GLP and ouabain induced lung edema, cell migration and activation, production of lipid mediators and cytokines and hemorrhage. They induced lung function alterations and inhibited rubidium incorporation. Using TLR4 knockout mice, we showed that the GLP action was not dependent on TLR4 activation. GLP activated of p38 and enhanced cytokine production in cell cultures which was reversed by a selective p38 inhibitor.ConclusionsGLP and ouabain induced lung injury, as evidenced by increased lung inflammation and hemorrhage. To our knowledge, this is the first report showing GLP induces lung injury. GLP and ouabain are Na/K-ATPase targets, triggering intracellular signaling pathways. We showed p38 activation by GLP-induced lung injury, which was may be linked to Na/K-ATPase inhibition. Lung inflammation induced by GLP was not dependent on TLR4 activation.

Structural and Mechanistic Investigation of Rubidium Ion Exchange in Potassium Zirconium Trisilicate

Complete and intermediate incorporation of rubidium into the hydrothermally prepared mineral umbite has been accomplished by ion exchange. Potassium zirconium trisilicate, K2ZrSi3O9·H2O, is an open...

Microcalorimetric Study of CO2and NH3Adsorption on Rb- and Sr-Modified Catalyst Supports

Acid−base characteristics of a series of rubidium- and strontium-modified materials were studied using adsorption microcalorimetry of ammonia and carbon dioxide. The samples were prepared by impregnation and decomposition of acetate precursors at 773 K on γ-alumina, titania, carbon, and silica. Microcalorimetric measurements showed that the incorporation of rubidium and strontium neutralized acid sites and created new base sites on the supports. However, the extent of these modifications depended on the compositions of both the basic additive and the support. Rubidium was more effective than strontium at altering the acid/base character of all the supports studied. The fewest base sites were found on modified silica, presumably due to the formation of surface silicate phases.