An all-soft-matter composite with exceptional electro-elasto properties is demonstrated by embedding liquid-metal inclusions in an elastomer matrix. This material exhibits a unique combination of high dielectric constant, low stiffness, and large strain limit (ca. 600% strain). The elasticity, electrostatics, and electromechanical coupling of the composite are investigated, and strong agreement with predictions from effective medium theory is found.

A highly active NiMo electrocatalyst for HOR in alkaline media with power density at 0.5 V higher than 100 mW cm−2 (peak value of 120 mW cm−2), which is similar to palladium was synthesized and comprehensively studied.

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We demonstrate the occurrence of electrokinetic phenomenon in paper substrates, by developing a simple "paper-and-pencil" device. The underlying electrokinetic phenomenon results in enhanced liquid transport through the paper-fibre matrix, which exhibits significant active electrical controllability and improved repeatability. These bear far-ranging consequences towards opening up a new paradigm of fluidics over small scales.

Zernike phase contrast is a useful technique for nanoscale X-ray computed tomography (CT) imaging of materials with a low X-ray absorption coefficient. It enhances the image contrast by phase shifting X-ray waves to create changes in amplitude. However, it creates artifacts that hinder the use of traditional image segmentation techniques. We propose an image restoration method that models the X-ray phase contrast optics and the three-dimensional image reconstruction method. We generate artifact-free images through an optimization problem that inverts this model. Though similar approaches have been used for Zernike phase contrast in visible light microscopy, this optimization employs an effective edge detection method tailored to handle Zernike phase contrast artifacts. We characterize this optics-based restoration method by removing the artifacts in and thresholding multiple Zernike phase contrast X-ray CT images to produce segmented results that are consistent with the physical specimens. We quantitatively evaluate and compare our method to other segmentation techniques to demonstrate its high accuracy.

A challenge faced by polymer electrolyte fuel cells for transportation applications is hydrogen starvation at the anode that can arise from a variety of sources such as water flooding, ice formation, foreign impurities, etc., which typically causes cell voltage reversals through water electrolysis and carbon corrosion at high anode potentials. Here we present electrochemical diagnostics and nano-scale X-ray computed tomography (nano-CT) of fuel cell electrodes with Pt/C catalysts degraded under cell voltage reversal conditions. It is found that the cell performance decreases and Ohmic resistance increases significantly after reversal tests. Anode cyclic voltammetry indicates new peaks due to severe carbon corrosion. Nano-CT imaging of the internal structure reveals that the thickness of the anode is reduced by approximately 40 % after the reversal tests, but the interface between the membrane and electrode appears mostly intact over the interfacial area even after the cell voltage reversals.