MXene‐based supercapacitors are promising electrochemical energy‐storage devices due to their ultrahigh volumetric capacitance, high‐power characteristics, and excellent cyclability. However, they suffer from severe self‐discharging behavior while the underlying self‐discharging mechanism is still unclear. Here, the self‐discharge behavior of MXene‐based supercapacitors from surface electronic structure of MXenes is disclosed, and a novel method to mitigate it is proposed. A superficial engineering strategy based on bio‐thermal treatment is developed to effectively tailor surface electronic structure of Ti3C2Tx MXenes by eliminating hydroxyl terminations. With the evolution of surface electronic structure, as revealed by Kelvin probe force microscope and synchrotron radiation X‐ray absorption fine structure analysis, MXene‐based supercapacitors with common aqueous electrolytes show >20% decline in self‐discharge rate. This decline mechanism originates from the increased work function that induces higher zero‐charge potential after the removal of hydroxyl groups in MXenes. Meanwhile, the strengthened surface dipole leads to higher surface free energy between MXene and electrolytes. These two positive effects endow MXenes with weaker self‐discharge kinetics. Specifically, the activation‐controlled self‐discharge process is greatly suppressed. Illuminating the relevance between electronic structure and self‐discharge accompanying superficial engineering suppression strategy can guide to development of high‐performance energy storage devices.

MXenes have received tremendous attention for flexible electronics owing to their excellent conductivity, water dispersibility, and mechanical flexibility. However, the sediment from the MXene production process is usually discarded as trash, resulting in low utilization. Here, we present a flexible pressure sensor that enables micro-force sensing and efficient utilization of MXene by confining MXene trash among structured MXene electrodes. Benefiting from the synergistic effect of both the confined micro-conical structure and easily changeable space of MXene trash, the as-designed device can detect extremely subtle pressure of 2.9 Pa, deliver a high sensitivity over 4.08 kPa −1 , and exhibit a remarkably fast response time (7 ms). These properties make it suitable for monitoring weak force signals from human wrist pulse and even for detecting dynamic responses associated with acoustic waves. This work provides a reference for the versatile and efficient application of MXene in the same device, showing great potential for sustainable production of next-generation wearable smart electronics.

A novel method to control the parameters of a chiral fiber grating structure is proposed. Mode couplings are controlled in real time during the twisting fabrication process. This chiral grating structure can satisfy the phase-matching condition for generating high-quality orbital angular momentum (OAM) beams, with an order mode of conversion efficiency over 99.9%. Both theoretical analysis and experimental results of this OAM mode conversion have been investigated, with good agreement. The results demonstrate a dual-OAM beam converter with a charge of ±1 for the right- and left-handed CLPGs, respectively. The high-quality OAM beam generated in this twisted single-mode fiber process may find excellent applications in optical communications.

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Objective. To evaluate the clinical efficacy of traditional Chinese medicine in the treatment of arrhythmia. Methods. The researchers searched CNKI, VIP, WF, PubMed, Web of Science, and Cochrane Library with the set-up themes as randomized controlled trials (RCTs) on the clinical efficacy of traditional Chinese medicine in the treatment of arrhythmia. This research evaluated all the retrieve literature and conducted selection based on the evaluation. Stata software was applied for meta-analysis. Results. 23 articles were retrieved with a total patient number of 2846. The results observed from the meta-analysis indicated the following: (1) compared with the result showed in placebo group, the traditional Chinese medicine group presented to have good efficacy, especially in the treatment of premature ventricular contractions. (2) In comparison with the western medicine group, the curative effect of Chinese medicine could approximately equal the therapeutic effect as western medicine. (3) Compared with the application of sole western medicine group, the combination of both traditional Chinese medicine and western medicine could have a better curative effect. Conclusion. In the treatment of arrhythmia disease, the application of traditional Chinese medicine can be considered as an effective method. In addition to that, the therapeutic effect obtained from the combination of both Chinese traditional medicine and western medicine is clinically better than that of the sole use of western medicine.