Herein, we have designed a highly active and robust trifunctional electrocatalyst derived from Prussian blue analogs, where Co₄N nanoparticles are encapsulated by Fe embedded in N-doped carbon nanocubes to synthesize hierarchically structured Co₄N@Fe/N–C for rechargeable zinc–air batteries and overall water-splitting electrolyzers. As confirmed by theoretical and experimental results, the high intrinsic oxygen reduction reaction, oxygen evolution reaction, and hydrogen evolution reaction activities of Co₄N@Fe/N–C were attributed to the formation of the heterointerface and the modulated local electronic structure. Moreover, Co₄N@Fe/N–C induced improvement in these trifunctional electrocatalytic activities owing to the hierarchical hollow nanocube structure, uniform distribution of Co₄N, and conductive encapsulation by Fe/N–C. Thus, the rechargeable zinc–air battery with Co₄N@Fe/N–C delivers a high specific capacity of 789.9 mAh g⁻¹ and stable voltage profiles over 500 cycles. Furthermore, the overall water electrolyzer with Co₄N@Fe/N–C achieved better durability and rate performance than that with the Pt/C and IrO₂ catalysts, delivering a high Faradaic efficiency of 96.4%. Along with the great potential of the integrated water electrolyzer powered by a zinc–air battery for practical applications, therefore, the mechanistic understanding and active site identification provide valuable insights into the rational design of advanced multifunctional electrocatalysts for energy storage and conversion.

Flexible, breathable, and highly sensitive pressure sensors have increasingly become a focal point of interest due to their pivotal role in healthcare monitoring, advanced electronic skin applications, and disease diagnosis. However, traditional methods, involving elastomer film-based substrates or encapsulation techniques, often fall short due to mechanical mismatches, discomfort, lack of breathability, and limitations in sensing abilities. Consequently, there is a pressing need, yet it remains a significant challenge to create pressure sensors that are not only highly breathable, flexible, and comfortable but also sensitive, durable, and biocompatible. Herein, we present a biocompatible and breathable fabric-based pressure sensor, using nonwoven fabrics as both the sensing electrode (coated with MXene/poly(3,4-ethylenedioxythiophene):polystyrene sulfonate [PEDOT:PSS]) and the interdigitated electrode (printed with MXene pattern) via a scalable spray-coating and screen-coating technique. The resultant device exhibits commendable air permeability, biocompatibility, and pressure sensing performance, including a remarkable sensitivity (754.5 kPa⁻¹), rapid response/recovery time (180/110 ms), and robust cycling stability. Furthermore, the integration of PEDOT:PSS plays a crucial role in protecting the MXene nanosheets from oxidation, significantly enhancing the device's long-term durability. These outstanding features make this sensor highly suitable for applications in full-range human activities detection and disease diagnosis. Our study underscores the promising future of flexible pressure sensors in the realm of intelligent wearable electronics, setting a new benchmark for the industry.

Ammonia serves as a crucial chemical raw material and hydrogen energy carrier. Aqueous electrocatalytic nitrogen reduction reaction (NRR), powered by renewable energy, has attracted tremendous interest during the past few years. Although some achievements have been revealed in aqueous NRR, significant challenges have also been identified. The activity and selectivity are fundamentally limited by nitrogen activation and competitive hydrogen evolution. This review focuses on the hurdles of nitrogen activation and delves into complementary strategies, including materials design and system optimization (reactor, electrolyte, and mediator). Then, it introduces advanced interdisciplinary technologies that have recently emerged for nitrogen activation using high-energy physics such as plasma and triboelectrification. With a better understanding of the corresponding reaction mechanisms in the coming years, these technologies have the potential to be extended in further applications. This review provides further insight into the reaction mechanisms of selectivity and stability of different reaction systems. We then recommend a rigorous and detailed protocol for investigating NRR performance and also highlight several potential research directions in this exciting field, coupling with advanced interdisciplinary applications, in situ/operando characterizations, and theoretical calculations.