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The structural stability of nanocatalysts during electrochemical CO2 reduction (CO2RR) is crucial for practical applications. However, highly active nanocatalysts often reconstruct under reductive conditions, requiring stabilization strategies to maintain activity. Here, we demonstrate that the N-heterocyclic carbene (NHC) polymer stabilizes Au nanowire (NW) catalysts for selective CO2 reduction to CO over a broad potential range, enabling coupling with Cu NWs for one-step tandem conversion of CO2 to C2H4. By combining the hydrophobicity of the polystyrene chain and the strong binding of NHC to Au, the polymer stabilizes Au NWs and promotes CO2RR to CO with excellent selectivity (>90%) across −0.4 V to −1.0 V (vs RHE), a significantly broader range than unmodified Au NWs (−0.5 V to −0.7 V). Stable CO2RR at negative potentials yields a high jCO of 142 A/g Au at −1.0 V. In situ ATR-IR analysis indicates that the NHC polymer regulates the water microenvironment and suppresses hydrogen evolution at high overpotential. Moreover, NHC-Au NWs maintain excellent stability during 10 h of CO2RR testing, preserving the NW morphology and catalytic performance, while unmodified NWs degrade into nanoparticles with reduced activity and selectivity. NHC-Au NWs can be coupled with Cu NWs in a flow cell to catalyze CO2RR to C2H4 with 58% efficiency and a partial current density of 70 mA/cm2 (overall C2 product efficiency of 65%). This study presents an adaptable strategy to enhance the catalyst microenvironment, ensure stability, and enable efficient tandem CO2 conversion into value-added hydrocarbons. 

Additive friction stir deposition (AFS-D) is considered a productive method of additive manufacturing (AM) due to its ability to produce dense mechanical parts at a faster deposition rate compared to other AM methods. Al6061 alloy finds extensive application in aerospace and nuclear engineering; nevertheless, exposure to radiation or high-energy particles over time tends to deteriorate their mechanical performance. However, the effect of radiation on the components manufactured using the AFS-D method is still unexamined. In this work, samples from the as-fabricated Al6061 alloy, by AFS-D, and the Al6061 feedstock rod were irradiated with He+ ions to 10 dpa at ambient temperature. The microstructural and mechanical changes induced by irradiation of He+ were examined using a scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and nanoindentation. This study demonstrates that, at 10 dpa of irradiation damage, the feedstock Al6061 produced a bigger size of He bubbles than the AFS-D Al6061. Nanoindentation analysis revealed that both the feedstock Al6061 and AFS-D Al6061 samples have experienced radiation-induced hardening. These studies provide a valuable understanding of the microstructural and mechanical performance of AFS-D materials in radiation environments, offering essential data for the selection of materials and processing methods for potential application in aerospace and nuclear engineering. 

Cutting-edge technologies of stretchable, skin-mountable, and wearable electronics have attracted tremendous attention recently due to their very wide applications and promising performances. One direction of particular interest is to investigate novel properties in stretchable electronics by exploring multifunctional materials. Here, we report an integrated strain sensing system that is highly stretchable, rehealable, fully recyclable, and reconfigurable. This system consists of dynamic covalent thermoset polyimine as the moldable substrate and encapsulation, eutectic liquid metal alloy as the strain sensing unit and interconnects, and off-the-shelf chip components for measuring and magnifying functions. The device can be attached on different parts of the human body for accurately monitoring joint motion and respiration. Such a strain sensing system provides a reliable, economical, and ecofriendly solution to wearable technologies, with wide applications in health care, prosthetics, robotics, and biomedical devices. 

Wearable electronics can be integrated with the human body for monitoring physical activities and health conditions, for human-computer interfaces, and for virtual/augmented reality. We here report a multifunctional wearable electronic system that combines advances in materials, chemistry, and mechanics to enable superior stretchability, self-healability, recyclability, and reconfigurability. This electronic system heterogeneously integrates rigid, soft, and liquid materials through a low-cost fabrication method. The properties reported in this wearable electronic system can find applications in many areas, including health care, robotics, and prosthetics, and can benefit the well-being, economy, and sustainability of our society.