Organohydrogel-based strain sensors are gaining attention for real-time health services and human-machine interactions due to their flexibility, stretchability, and skin-like compliance. However, these sensors often have limited sensitivity and poor stability due to their bulk structure and strain concentration during stretching. In this study, we designed and fabricated diamond-, grid-, and peanut-shaped organohydrogel based on positive, near-zero, and negative Poisson’s ratios using digital light processing (DLP)-based 3D printing technology. Through structural design and optimization, the grid-shaped organohydrogel exhibited record sensitivity with gauge factors of 4.5 (0–200% strain, ionic mode) and 13.5/1.5 × 10⁶ (0−2%/2%−100% strain, electronic mode), alongside full resistance recovery for enhanced stability. The 3D-printed grid structure enabled direct wearability and breathability, overcoming traditional sensor limitations. Integrated with a robotic hand system, this sensor demonstrated clinical potential through precise monitoring of paralyzed patients’ grasping movements (with a minimum monitoring angle of 5°). This structural design paradigm advanced flexible electronics by synergizing high sensitivity, stability, wearability, and breathability for healthcare, and human-machine interfaces.

The notorious growth of sodium dendrites and significant volume fluctuations have posed substantial challenges to the practical application of sodium metal anodes. In this work, an aerogel composed of MgF₂ nanoparticles (NPs) onto a three-dimensional (3D) printed reduced graphene oxide (rGO) (MgF₂/rGO) monolith was employed as a scaffold for sodium metal anodes. During the initial discharge process, the MgF₂ NPs underwent an electrochemical in-situ conversion into NaF and sodiophilic Mg NPs, which act as the Na metal nucleation centers and contribute to the formation of a stable solid electrolyte interface (SEI) layer. Benefiting from these synergistic effects, the 3D printed MgF₂/rGO electrode exhibits a high Coulombic efficiency of 99.49% after 1200 cycles at 0.5 mA·cm⁻² with 1 mAh·cm⁻². It also shows a long cycle lifespan of 2500 h with a high capacity of 10 mAh·cm⁻² at 5 mA·cm⁻². Moreover, when assembled into a full cell with a Na@MgF₂/rGO anode and a Na₃V₂(PO₄)₃@C-rGO cathode, the cell delivers an extended cycle life of 3500 cycles at 1 C, preserving a reversible capacity of 86.98 mAh·g⁻¹. This work paves the way for utilization of 3D printed metal-fluorides to enhance the electrochemical performance of the sodium metal anodes.

Lithium metal has been considered one of the most promising anodes for next-generation rechargeable batteries, but its practical application is largely hindered by the uncontrollable dendrite growth and infinite volume change. Here, inspired by superior catalytic effects of single-atom catalysts, carbonsupported single atomic Co with asymmetric N, O-coordination (Co-N/O) is developed for Li metal battery. Experimental results and theoretical calculations indicate that single atomic Co atoms with asymmetric N, O-coordination present enhanced binding ability toward Li in comparison with N-coordinated atomic Co site and isolated O site, enabling uniform Li plating/stripping. Moreover, the asymmetric N, O-coordination around Co atoms induces co-activation effects, lowering the energy barriers toward Li⁺ to Li⁰ conversion and largely promoting the deposition kinetics. When used as a Li deposition host, the Co-N/O achieves a high average coulombic efficiency of 98.6% at a current density of 1 mA cm⁻² and a capacity of 2 mAh cm⁻², long cycling life of 2000 h in symmetrical cells, and excellent rate performance (voltage hysteresis of 23 mV at 8 mA cm⁻²). This work provides a comprehensive understanding of single atomic metals with asymmetric heteroatom coordination in the design of Li metal anode.

Regarding the reverse process of materials growth, etching has been widely concerned to indirectly probe the growth kinetics, offering an avenue in governing the growth of two-dimensional (2D) materials. In this work, interface-driven anisotropic etching mode is demonstrated for the first time to be generally applied to 2D heterostructures. It is shown that the typical in-plane graphene and hexagonal boron nitride (h-BN) heterostructures follow a multi-stage etching behavior initiated first along the interfacial region between the two materials and then along edges of neighboring h-BN flakes and finally along central edges of h-BN. By accurately tuning etching conditions in the chemical vapor deposition process, series of etched 2D heterostructure patterns are controllably produced. Furthermore, scaled formation of graphene and h-BN heterostructures arrays has been realized with full assist of as-proposed etching mechanism, offering a direct top-down method to make 2D orientated heterostructures with order and complexity. Detection of interface-driven multi-staged anisotropic etching mode will shed light on understanding growth mechanism and further expanding wide applications of 2D heterostructures.

Li metal anode holds great promise to realize high-energy battery systems. However, the safety issue and limited lifetime caused by the uncontrollable growth of Li dendrites hinder its commercial application. Herein, an interlayer-bridged 3D lithiophilic rGO-Ag-S-CNT composite is proposed to guide uniform and stable Li plating/stripping. The 3D lithiophilic rGO-Ag-S-CNT host is fabricated by incorporating Ag-modified reduced graphene oxide (rGO) with S-doped carbon nanotube (CNT), where the rGO and CNT are closely connected via robust Ag-S covalent bond. This strong Ag-S bond could enhance the structural stability and electrical connection between rGO and CNT, significantly improving the electrochemical kinetics and uniformity of current distribution. Moreover, density functional theory calculation indicates that the introduction of Ag-S bond could further boost the binding energy between Ag and Li, which promotes homogeneous Li nucleation and growth. Consequently, the rGO-Ag-S-CNT-based anode achieves a lower overpotential (7.3 mV at 0.5 mA cm⁻²), higher Coulombic efficiency (98.1% at 0.5 mA cm⁻²), and superior long cycling performance (over 500 cycles at 2 mA cm⁻²) as compared with the rGO-Ag-CNT- and rGO-CNT-based anodes. This work provides a universal avenue and guidance to build a robust Li metal host via constructing a strong covalent bond, effectively suppressing the Li dendrites growth to prompt the development of Li metal battery.

Aqueous alkaline battery represents a promising energy storage technology with both high energy density and high power density as rechargeable batteries. However, the low theoretical capacities, kinetics and stability of anode materials have limited their developments and commercializations. In this study, we propose a novel method to produce two-dimensional layered bismuth oxide selenium (Bi₂O₂Se) and reduced graphene oxide (rGO) composites via a one-step hydrothermal method. The volume change caused by phase change during rapid charging and discharging is significantly reduced and the capacity reaches 263.83 mAh g⁻¹ at a current density of 0.5 A g⁻¹. The Bi₂O₂Se/rGO electrode exhibits excellent cycling stability in which the capacity retention rate is 81.04% after 5000 cycles. More importantly, the Bi₂O₂Se/rGO nanosheet composite is used as the anode electrode material with MnCo₂O_4.5@Ni(OH)₂ as the cathode electrode material in aqueous alkaline battery. When the energy density is 76.16 W h kg⁻¹, the power density reaches 308.65 W kg⁻¹. At a power density of 10.21 kW kg⁻¹, the energy density remains as high as 33.86 W h kg⁻¹. The results presented here may advance the understanding of the issues facing the development of aqueous battery anode materials.