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In this work, we reported a series of monolithic 3D‐printed Ni–Mo alloy electrodes for highly efficient water splitting at high current density (1500 mA cm−2) with excellent stability, which provides a solution to scale up Ni–Mo catalysts for HER to industry use. All possible Ni–Mo metal/alloy phases were achieved by tuning the atomic composition and heat treatment procedure, and they were investigated through both experiment and simulation, and the optimal NiMo phase shows the best performance. Density functional theory (DFT) calculations elucidate that the NiMo phase has the lowest H2O dissociation energy, which further explains the exceptional performance of NiMo. In addition, the microporosity was modulated via controlled thermal treatment, indicating that the 1100 °C sintered sample has the best catalytic performance, which is attributed to the high electrochemically active surface area (ECSA). Finally, the four different macrostructures were achieved by 3D printing, and they further improved the catalytic performance. The gyroid structure exhibits the best catalytic performance of driving 500 mA cm−2 at a low overpotential of 228 mV and 1500 mA cm−2 at 325 mV, as it maximizes the efficient bubble removal from the electrode surface, which offers the great potential for high current density water splitting. [ABSTRACT FROM AUTHOR]

Zirconia‐toughened alumina (ZTA) composite ceramics show great potential for use in dental repair applications due to their unique properties. Complex‐shaped ZTA all‐porcelain crowns can be accurately fabricated using digital light processing (DLP) technology. However, effectively controlling both the anisotropy on mechanical property and surface quality of ZTA composites shaped by DLP remains a critical challenge that requires further research and innovation. In this work, we propose an efficient method to synchronously enhance the isotropy on mechanical performance and surface quality of DLP formed ZTA all‐porcelain crowns by controlling contents of yttria‐stabilized zirconia (YSZ) powders. When enhancing contents of YSZ from 5 to 20 wt%, multilayer microstructure with obvious interlayer gaps transformed into uniform microstructure with strong interlayer bonding, and the smaller alumina grain was observed on the stair‐stepping microstructure. Finally, the ZTA composites exhibited flexural and comprehensive strength as high as 640.3 and 6.9 MPa, and dimensional precision as low as 37.5 and 43.5 μm on top and side surface, together with simultaneously enhanced isotropy on mechanical property and surface quality, well satisfying the demands for all‐porcelain crowns fabricating. This study provides thorough understandings on isotropy regulating of DLP‐shaped ZTA all‐porcelain crowns with excellent mechanical performance and surface quality. [ABSTRACT FROM AUTHOR]

For high-performance flexible supercapacitors (FSCs), electrodes with high capacitance and flexibility play a significant role in determining the electrochemical behavior for their applications. Herein, conductive polymer hydrogel (CPH) electrodes have been successfully synthesized via in situ polymerization of aniline (ANI) in an aqueous solution of polyvinyl alcohol (PVA), phytic acid (PA), and hydroquinone (HQ), in which PA acted as a crosslinking agent and HQ served as an effective organic redox additive. The incorporation of HQ is expected to enhance the capacitance of conductive PHP hydrogel electrodes. The effective redox additive HQ incorporated PANI/HQ/PVA (PHP) hydrogel electrode exhibited a favorable specific capacitance of 642 F g−1 at 0.5 A g−1, which was much higher than the pristine one without introducing any redox additive (421 F g−1 at 0.5 A g−1) due to the extra redox reaction. Additionally, the PHP hydrogel electrode also showed excellent flexibility (93.3% capacitance retention after 500 cycles of bending) and superior cycling stability (81.5% after 10 000 cycles). For practical application, the all-hydrogel-state FSCs assembled with redox additive HQ incorporated PHP hydrogel electrodes and PVA/H2SO4 electrolyte delivered a high energy density of 12 W h kg−1 at a power density of 125 W kg−1, which was remarkably larger than that of PP-based FSCs (7.85 W h kg−1). The supercapacitor demonstrated prolonged cycling stability with a capacitance retention of 77.6% up to 10 000 charge/discharge cycles. This work provides a novel design for conductive polymer hydrogel electrodes with prospective applications in next-generation flexible energy storage devices. [ABSTRACT FROM AUTHOR]