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Gallium oxide (Ga2O3), with an ultrawide bandgap corresponding to the deep ultraviolet (DUV) range, has attracted significant attention in optical filter‐free photodetectors. In practical terms, DUV photodetectors employed in extreme conditions, for example, flame detection and space exploration, face the challenges of performance degradation caused by high/low‐temperature transformation. Here, DUV photodetectors are tailored with high durability and stability by one‐step‐grown β‐Ga2O3 films via pulsed laser deposition. A high‐oxygen‐pressure scheme effectively addresses the issue of film‐free deposition at specifically high temperatures, facilitating the formation of polycrystalline high‐resistivity β‐Ga2O3 films. As a result, the devices exhibit outstanding performance, including a low dark current (4.4 pA @30 V), high photoresponsivity (147.36 A W−1), and fast response time (3.1/22.6 ms). Additionally, the photoresponse performance shows minimal degradation at high temperatures up to 300 °C and even improves at low temperatures down to −100 °C, ranking it among the most robust DUV photodetectors. The mechanism of photoresponse, involving the exciton formation, bandgap evolution, carrier‐phonon scatter, etc., is also elucidated in a wide temperature range. This work provides an efficient solution for developing robust Ga2O3 DUV photodetectors with excellent performance for extreme‐condition applications. [ABSTRACT FROM AUTHOR]

The work presented an electrochemical anode method with different electrolyte concentrations and heat posttreatment to control the stoichiometry and structure of Cu2−xS electrocatalysts. X‐ray diffraction, X‐ray photoelectron spectroscopy, and scanning electron microscopy were employed to characterize the composition and morphology, whereas the electrocatalytic activity was evaluated by linear scanning voltammetry and electrochemical impedance spectroscopy. The results showed that the electrochemical method successfully synthesized thin flake‐shaped Cu7S4, which exhibited optimal performance at the electrolyte concentration of 0.45 mol L1 with maximum turnover frequency of 0.786 s−1, maximum mass activity of 0.539 A g−1, minimum charge transfer resistance of 0.156 Ω cm−2, and minimum overpotential of 154 mV at a current density of 10 mA cm−2. In the Cu7S4 structure, Cu2+ and S2− were coordinated in a CuS4 tetrahedral structure, whereas Cu+ and S2− were coordinated in a CuS3 triangular structure. Heat posttreatment could change the stoichiometry from 1.75 to 1.8 and improve the electrochemical performance. In the Cu9S5 structure, the CuS3 triangular structure had disappeared. Under the same conditions, the overvoltage was only 128 mV. [ABSTRACT FROM AUTHOR]

In this study, a heterotrophic/biofilm‐electrode autotrophic denitrification reactor (HAD‐BER) was constructed and nano‐ɑ‐Fe2O3 was coated on granular activated carbon (GAC) as a third electrode to enhance the nitrate removal performance. The introduction of nano‐ɑ‐Fe2O3 could stimulate microorganisms to secrete more extracellular polymeric substances (EPS), accelerating the electron transfer. Moreover, more denitrification bacteria were enriched on the particle electrodes, especially Pseudomonas and Thermomonas, which played a significant role in denitrification. The denitrification performance at different COD/N ratios (0.65–3.23) and current intensities (0–150 mA) was investigated in depth. When the nitrate concentration of the influent was 60 mg/L, nitrate was almost completely removed at the optimal current intensity (60 mA) and COD/N ratio (1.29). At the same time, there was almost no nitrite (<0.10 mg/L) and ammonia nitrogen (0 mg/L) accumulation in the effluent. This study provided a new direction for the advancement of HAD‐BER and accelerated its implementation. Practitioner Points: By introducing nano‐a‐Fe2O3 into HAD‐BER, more denitrification bacteria were enriched on the particle electrodes.The increased contents of polysaccharide and protein content could accelerate the electron transfer.Almost completely denitrification could be achieved at current = 60 mA and COD/N = 1.29.The study provided a new direction for the further development of HAD‐BERs. [ABSTRACT FROM AUTHOR]

Wine‐processed Angelica Sinensis is a widely used Chinese medicinal decoction piece in China. However, there are hardly any robust markers indicating the processing procedure of wine‐processed Angelica Sinensis, including the amount of rice wine and processing degree. A strategy integrating untargeted metabolomics and chemometric analysis for deducing robust markers was provided and applied to the discrimination of processing procedure. First, 86 compounds were tentatively identified in wine‐processed Angelica Sinensis by ultra‐high‐performance liquid chromatography coupled with quadrupole‐time of flight mass spectrometry. Second, 93 potential chemical markers were selected using multivariate analysis, among which nine robust chemical markers were selected by verification with commercial samples. Finally, the effects of processing temperature, time, and amount of rice wine on the three selected chemical markers were investigated through a rapid analytical method. It was demonstrated that both m/z 258.1097 and 238.1189 were positively correlated with the amount of rice wine and processing degree. In summary, this study introduced two candidate processing markers as robust markers for discriminating the processing procedures of wine‐processed Angelica sinensis. It also proposed a strategy to provide the reference for the research of other decoction pieces. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: As the third generation new battery, the power conversion efficiency (PCE) of metal halide perovskite solar cells (PSCs) has increased from 3.8% in 2009 to 25.8% currently certified, which fully shows that they have great research value and development prospect. As one of the main components of high‐efficiency PSCs, hole transport materials (HTMs) play an important role in extracting and transporting holes and inhibiting charge recombination. However, commonly used HTMs require doping, and the hygroscopicity and corrosiveness of the dopants will destroy the stability of PSCs and hinder their commercialization. Therefore, it is of great significance to develop dopant‐free HTMs. In this review, the dopant‐free HTMs in recent six years are reviewed and summarized systematically, including organic small molecules, polymers and cross‐linkable materials. We focus on the design of the molecular cores and discuss their structure–property correlation, conductivity, and photovoltaic performance. Finally, how to design an ideal HTM is summarized. We hope that this review can provide reference for the development of low‐cost and dopant‐free HTMs to prepare efficient and stable PSCs. [ABSTRACT FROM AUTHOR]

The processing of Traditional Chinese Medicine requires the appropriate parameters, while the specific chemical markers are still absent to obtain the optimized processing. In this study, we used vinegar‐baked Euphorbia kansui as a case to dissect the chemical markers for the baking process using untargeted metabolomics. The robust chemical markers were selected based on the three rules, correlation, significant difference, and controllability. All the differential features were categorized based on their mass defects. After the differential analysis, 310 differential compounds were screened out and could be mainly divided into six categories: diacylglycerols and triacylglycerols demonstrated increasing trends with the baking time in the discriminant model, while ingenane‐type diterpenes, jatrophane‐type diterpenes, fatty acid esters, and fatty acids had decreasing trends. It was unexpected to find that the diterpenes did not correlate with the baking time. Only very few compounds meet the three rules. They were validated with a high‐performance liquid chromatography method. Finally, only 13‐Hydroxy‐9,11‐octadecadienoic acid and its isomer 9‐Hydroxy‐10,12‐octadecadienoic acid could be used further to differentiate the commercial vinegar‐baked Euphorbia kansui. It would be of interest to evaluate whether these two compounds could be utilized as markers to control more processing methods in future studies. [ABSTRACT FROM AUTHOR]