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Electrolyte additives with multiple functions enable the interfacial engineering of Li‐metal batteries (LMBs). Owing to their unique reduction behavior, additives exhibit a high potential for electrode surface modification that increases the reversibility of Li‐metal anodes by enabling the development of a hierarchical solid electrolyte interphase (SEI). This study confirms that an adequately designed SEI facilitates the homogeneous supply of Li+, nonlocalized Li deposition, and low electrolyte degradation in LMBs while enduring the volume fluctuation of Li‐metal anodes on cycling. An in‐depth analysis of interfacial engineering mechanisms reveals that multilayered SEI structures comprising mechanically robust LiF‐rich species, electron‐rich P–O species, and elastic polymeric species enabled the stable charge and discharge of LMBs. The polymeric outer SEI layer in the as‐fabricated multilayered SEI could accommodate the volume fluctuation of Li‐metal anodes, significantly enhancing the cycling stability Li||LiNi0.8Co0.1Mn0.1O2 full cells with an electrolyte amount of 3.6 g Ah−1 and an areal capacity of 3.2 mAh cm−2. Therefore, this study confirms the ability of interfacial layers formed by electrolyte additives and fluorinated solvents to advance the performance of LMBs and can open new frontiers in the fabrication of high‐performance LMBs through electrolyte‐formulation engineering. [ABSTRACT FROM AUTHOR]

This study investigates the impact of resonant acoustic powder mixing on the delay time of the W–KClO4–BaCrO4 (WKB) mixture and its potential implications for powder and material synthesis. Through thermal analysis, an inverse linear relationship was found between thermal conductivity and delay time, allowing us to use thermal conductivity as a reliable proxy for delay time. By comparing the thermal conductivity of WKB mixtures mixed manually and using an acoustic powder mixer, we found that acoustic powder mixing resulted in minimal deviations in thermal conductivity, proving more uniform mixing. Furthermore, differential scanning calorimeter analysis and Sestak–Berggren modeling demonstrated consistent reaction dynamics with a constant activation energy as the reaction progressed in samples mixed using acoustic waves. These findings underscore the critical role of uniform powder mixing in enhancing the thermodynamic quality of the WKB mixture and emphasize the importance of developing novel methods for powder and material synthesis. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HAp), a main constituent of the cortical bone, retains a large surface charge that plays a critical role in the regeneration of bones, whose source remains an enigma. Here, we used multi-eigenmode piezoresponse force microscopy via Pearson correlation and conducted multiscale material analysis to independently measure the piezoelectric coefficient and the surface charge density of HAp. Quantitative comparison was conducted between the measured surface charge density and the conceptual values computed for all possible candidates of the surface charging such as piezoelectricity, chemically induced surface charging, flexoelectricity, and defect dipole moment. The results presented Ca2+ ions released during local calcium orthophosphate phase transition at the surface as the main source of the surface charging. Further analysis showed that the ion concentration was modulable using a charged conductive tip, implying that the interstitial ions are mobile within the HAp matrix. In this work, we developed a novel method to measure the effective surface charge density of arbitrary material systems, thereby facilitating the investigation of biophysical phenomena related to surface electromechanics. Most importantly, the research promotes a new understanding of the origin of osteoconduction observed in past works conducted on HAp. [ABSTRACT FROM AUTHOR]

The intraoperative active bleeding (iAB) detection model can be used for image-guided surgery and as a significant statistical index in predicting patient outcomes after surgery. However, detecting iAB is difficult due to the similarity between active and non-active bleeding or active bleeding in a small area. Using the spatial and temporal characteristics of the iAB area within frames simultaneously can overcome this. We propose a novel training method that can adequately fuse image segmentation and temporal action localisation models for effective iAB detection. The proposed active bleeding detection model has the following supervision process: First, annotate temporal localisation information for active bleeding that is relatively easy to annotate. Next, in the active bleeding section, where temporal localisation is annotated, spatial localisation information for selected frames is annotated and used as auxiliary information for active bleeding detection. We constructed a cross-validation set of 40 robotic subtotal gastrectomies and verified the ability of an active bleeding model guided by image segmentation information to bring improvements to the active bleeding recognition task. In addition, we applied performance evaluation for outcome analysis by measuring errors in iAB duration and counting in surgical videos for each algorithm.1 [ABSTRACT FROM AUTHOR]

Piezoresponse force microscopy (PFM) uses a cantilever arm to track the electromechanical motion of the electric dipole moment to visualize the ferroelectric domain structure, which provides an important insight into the physics of switchable electric polarization—especially for memory devices and integrated microelectronics. Here, I provide a tutorial on single frequency vertical PFM, the most basic mode of PFM. I will start with the basic components of atomic force microscopy (AFM), including tip, cantilever, X–Y stage, Z actuator, and lock-in amplifier. Contact mode AFM will be briefly explained and discussed, where you can find two modes: constant deflection and constant height modes. Single-frequency vertical PFM splits the frequency domain of tip vibration into low and high frequencies and uses a low-pass filter to nullify any motion caused by topography (constant deflection). In contrast, the lock-in amplifier will pinpoint the vibration induced by the vertical piezoelectric strain along the sample's surface normal (constant height). This tutorial will provide an overall and detailed step by step instruction to conduct PFM imaging and piezoresponse hysteresis loop measurement using atomic force microscopy and a lock-in amplifier and teach how to interpret the PFM images and the piezoresponse hysteresis loops for various applications. [ABSTRACT FROM AUTHOR]

Activation of metal oxides by light is a robust yet facile approach to manipulating their surface chemistry for favorable reactions with target molecules in heterogeneous catalysis and gas sensors. However, a limited understanding of interface chemistry and the involved mechanism impedes the development of a rational design of oxide interfaces for light‐activated gas sensing. Herein, the TiOx‐assisted photosensitization of In2O3 toward NO2 sensing is investigated as a case study to elucidate the detailed mechanism of light‐activated surface chemistry at the metal/gas interface. The resultant heterogeneous oxides exhibit outstanding NO2 sensing performance under light irradiation thanks to abundant photoexcited electrons and holes that serve as adsorption and desorption sites, respectively, to accelerate both surface reactions. Furthermore, the facile transfer of electrons and holes across the TiOx‐In2O3 interface contributes to improving the reversibility of sensing kinetics. Through this study, the mechanistic understanding is established of how the surface chemistry of metal oxide surfaces can be tuned by light activation providing an effective route to the design fabrication of high‐performance gas sensors. [ABSTRACT FROM AUTHOR]