Attaining carbon neutrality requires the development of aqueous energy conversion and storage devices. However, the performance of these devices is limited by the permeability-selectivity trade-off of permselective membranes as core components. Herein, we report a synergistic approach utilizing two-dimensional nanoribbons-entangled nanosheets to rationally balance the permeability and selectivity in permselective membranes. The nanoribbons and nanosheets can be self-assembled into a nanofluidic membrane with a distinctive “island-bridge” configuration, where nanosheets as isolated islands offer adequate ionic selectivity owing to their high surface charge density, meanwhile bridge-like nanoribbons with low surface charge density but high aspect ratio remarkably enhance the membrane’s permeability and water stability, as verified by molecular simulations and experimental investigations. Using this approach, we develop a high-performance graphene oxide (GO) nanosheets/GO nanoribbons (GONR) nanofluidic membrane, achieving an ultrahigh power density of 18.1 W m^–2 in natural seawater|river water osmotic power generator, together with high Coulombic efficiency and extended lifespan in zinc metal batteries. The validity of our island-bridge structural design is also demonstrated for other nanosheet/nanoribbon composite membranes, providing a promising path for developing reliable aqueous energy conversion and storage devices.

Carbon materials are key components in energy storage and conversion devices and most directly impact device performance. The need for advanced carbon materials has become more pressing with the increasing demand for high-performance energy conversion and storage facilities. Nonetheless, realizing significant performance improvements across devices remains challenging because of the difficulties in controlling irregularly organized microstructures and the specific carbon structures concerned. With the aim of realizing devisable structures, adjustable functions, and performance breakthroughs, this review proposes the concept of superstructured carbons. In fact, superstructured carbons are a category of carbon-based materials characterized by precisely built pores, networks, and interfaces. This unique category meets the particular functional demands of high-performance devices and exceeds the rigid structure of traditional carbons. In the context of these superstructured carbons, we present methods for realizing both custom-built structures and target-oriented functionalities. For specific energy-related reactions, we emphasize the targeted property-structure relationships in these well-defined superstructured carbons. Finally, future developments and practicability challenges of superstructured carbons are also proposed.

For anode-free lithium metal battery, lithiophilic surface modification on the current collector can effectively reduce the lithium nucleation barrier, so as to regulate the electrodeposition of lithium. Here, atomically dispersed Zn-(C/N/O) lithiophilic sites in the amorphous carbon medium were introduced onto Cu by an in-situ induced ion coordination chemistry strategy to get the modified Zn@NC@RGO@Cu current collector. X-ray absorption spectroscopy (XAS) combined with scanning transmission electron microscopy in high angle annular dark field (STEM-HAADF) analysis proved the single atomic state of the zinc sites surrounded by C, N, and O with a coordination number of ~ 3. According to the electrochemical tests and first principle calculations, the ultra-uniformly dispersed Zn-(C/N/O) sites at the atomic level can effectively improve the lithium affinity, reduce the energy barrier for lithium nucleation, homogenize the lithium nucleation, and enhance an inorganic lithium compounds rich solid electrolyte interphase layer. As a result, the nucleation overpotential of lithium on the modified current collector was reduced to 7.7 mV, which was 5.4 times lower than that on bare Cu. Uniform lithium nucleation and deposition enabled stable Li plating/stripping and elevated Coulombic efficiency of 98.95% in Li||Cu cell after > 850 cycles. Capacity retention of 89.7% was successfully achieved in the anode-free lithium metal battery after 100 cycles.

TiO₂ has been considered as an ideal photocatalyst for water splitting. However, narrow light absorbance, low charge separation efficiency, and rare surface active sites lead to the low photocatalytic efficiency of TiO₂. Although extensive research attempted to improve the situation, there is still lack of method for constructing high active and noble-metal-free TiO₂ photocatalyst for H₂ evolution reactions (HER). In this work, we loaded single atomic (SA) Ni (or Co) on the surface of anatase TiO₂ (TiO₂(A)) nanosheets by an isolation strategy. Ethylene diamine tetraacetic acid and ethylene glycol (EDTA-EG) compounds were used to chelate metal ions in solution and form carbon quantum dots in the following thermal treatment to isolate the metal ions on surface of TiO₂(A). The prepared Ni SA/TiO₂(A) catalyst owned a “skin wrapped body” structure with in-situ formed two-dimensional (2D) heterojunction facilitating the fast electron transfer. As a result, the Ni SA/TiO₂(A) catalyst showed a high H₂ evolution rate of 2,900 μmol·g⁻¹·h⁻¹. This work provides an isolation strategy for constructing promising single-atom metal catalyst for photocatalysis and beyond.