Organic–inorganic hybrid perovskite solar cells (PVSCs) have become the front‐running photovoltaic technology nowadays and are expected to profoundly impact society in the near future. However, their practical applications are currently hampered by the challenges of realizing high performance and long‐term stability simultaneously. Herein, the development of inverted PVSCs is reported based on low temperature solution‐processed CuCrO2 nanocrystals as a hole‐transporting layer (HTL), to replace the extensively studied NiOx counterpart due to its suitable electronic structure and charge carrier transporting properties. A ≈45 nm thick compact CuCrO2 layer is incorporated into an inverted planar configuration of indium tin oxides (ITO)/c‐CuCrO2/perovskite/[6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM)/bathocuproine (BCP)/Ag, to result in the high steady‐state power conversion efficiency of 19.0% versus 17.1% for the typical low temperature solution‐processed NiOx‐based devices. More importantly, the optimized CuCrO2‐based device exhibits a much enhanced photostability than the reference device due to the greater UV light‐harvesting of the CuCrO2 layer, which can efficiently prevent the perovskite film from intense UV light exposure to avoid associated degradation. The results demonstrate the promising potential of CuCrO2 nanocrystals as an efficient HTL for realizing high‐performance and photostable inverted PVSCs.
Conversion of waste to high-value products by pyrolysis is a suitable and harmless disposal technology for the abundant waste generated in the tobacco industry. To determine the optimum operational parameters for biomass pyrolytic polygeneration using tobacco waste as the feedstock, the product characteristics and nitrogen transformation were investigated from 250 to 950 °C. The highest low calorific values of gas and char were 13 MJ/m 3 at 750 °C and 15 MJ/kg at 450 °C, respectively. The optimum operating temperature recommended for biomass pyrolytic polygeneration of tobacco waste is 650 °C when the three products (char, oil, and gas) are balanced. The char formation process is divided into three stages: degradation (250−450 °C), reforming (450−650 °C), and condensation (>650 °C). Three types of N-containing structures are formed in chars: pyridinic N, pyrrolic/pyridine N, and quaternary N. Pyridinic N is dominant at low temperatures, whereas quaternary N becomes dominant at high temperatures. N-containing volatiles escape from chars with increasing temperature and are primarily found in oil below 550 °C and in gas above 650 °C. N-containing compounds are the major components (up to 45%) in the organic portion of oil, with pyridines, pyrroles, and piperidines as the dominant forms. In the gas product, NH 3 and HCN are the major N-containing compounds released above 650 °C. This study is expected to be beneficial for the comprehensive utilization of tobacco waste.
The authors present an idealized theoretical and numerical study of tsunami-induced internal waves in the atmosphere. These are gravity waves modified by acoustic effects that can propagate rapidly from the ocean surface up to the ionosphere, where they are well known to leave a detectable fingerprint in airglow patterns and other remote sensing observables. Accurate modeling of the wave propagation is a prerequisite for being able to detect and decode this transient observational fingerprint by remote sensing methods. The authors study this problem by formulating the initial-value problem for linear waves forced by an idealized tsunami at the lower boundary and then employing a semianalytic Fourier-Laplace method to solve it. This approach allows them to compute the detailed time evolution of the waves while ensuring that the correct radiation condition in the vertical is satisfied at all times, a nontrivial matter for these transient waves.The authors also compare the predictions of an anelastic model with that of a fully compressible model in order to discern the importance of acoustic effects. The findings demonstrate that back-reflection at the tropopause is a significant factor for the structure of these waves and that the earliest observable signal in the ionosphere is, in fact, a fast acoustic precursor wave generated by the nearly impulsive formation of the tsunami itself.
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