Controlling the structure of graphene‐based materials with improved ion intercalation and diffusivity is crucial for their applications, such as in aluminum‐ion batteries (AIBs). Due to the large size of AlCl4− ions, graphene‐based cathodes have specific capacities of ≈60 to 148 mAh g−1, limiting the development of AIBs. A thermal reductive perforation (TRP) strategy is presented, which converts three‐layer graphene nanosheets to surface‐perforated graphene materials under mild temperature (400 °C). The thermal decomposition of block copolymers used in the TRP process generates active radicals to deplete oxygen and create graphene fragments. The resultant material has a three‐layer feature, in‐plane nanopores, >50% expanded interlayer spacing, and a low oxygen content comparable to graphene annealed at a high temperature of ≈3000 °C. When applied as an AIB cathode, it delivers a reversible capacity of 197 mAh g−1 at a current density of 2 A g−1 and reaches 92.5% of the theoretical capacity predicted by density‐functional theory simulations.

Selenium (Se) based rechargeable aluminium batteries (RABs), known as aluminium-selenium (Al-Se) batteries, are an appealing new battery design that holds great promise for addressing the low-capacity problem of current RAB technology. However, their applications are hindered by mediocre high-rate capacity (~100 mAh g-1 at 0.5 A g-1) and insufficient cycling life (50 cycles). Herein, we report the synthesis of mesoporous carbon fibers (MCFs) by coating mesoporous carbon with short-length mesopores and tunable mesopore sizes (2.7 to 8.9 nm) coaxially on carbon nanotubes (CNT). When compositing MCFs with Se for Al-Se batteries, a positive correlation between mesopore size and electrolyte ion diffusivity has been observed, however when pore size is increased to 8.9 nm, large voids are created at the interface of CNT core and mesoporous carbon shell, leading to decreased electrode conductivity. The trade-off between ion diffusivity and interfacial connectivity/conductivity determines MCF with pore size of 7.1 nm as the best host material for Al-Se batteries. The composite cathode delivers high specific capacities (366, 230 mAh g-1 at 0.5, 1 A g-1), good rate performance and excellent cycling stability (152 mAh g-1 after 500 cycles at 2 A g-1), superior over previously reported Se cathodes and other cathodes for RABs. Received: ((will be filled in by the editorial staff)) Revised: ((will be filled in by the editorial staff))

Hollow spheres are charming objects in nature. In this work, an unexpected deflation–inflation asymmetric growth (DIAG) strategy is reported, generating hollow nanoparticles with tailored concave geometry for interface catalysis. Starting from aminophenol‐formaldehyde (APF) nanospheres where the interior crosslinking degree is low, fully deflated nanobowls are obtained after etching by acetone. Due to APF etching and repolymerization reactions occuring asymmetrically within a single particle, an autonomous inflation process is observed similar to a deflated basketball that inflates back to a “normal” ball, which is rare at the nanoscale. A nucleophilic addition reaction between acetone and APF is elucidated to explain the chemistry origin of the DIAG process. Interestingly, the deflated APF hollow spheres enable preferential immobilization of lipase in the concave domain, which facilitates the stabilization of Pickering emulsion droplets for enhanced enzymatic catalysis at the oil–water interface. The study provides new understandings in the designable synthesis of hollow nanoparticles and paves the way toward a wide range of applications of asymmetric architectures.

Lateral flow immunoassays (LFIAs) have drawn much attention in point-of-care diagnostic applications, and the development of high-performance label materials is the key. In this study, the impact of the surface chemistry of dendritic mesoporous silica nanoparticles (DMSNs) on their enrichment performance toward quantum dots (QDs) and signal amplification of the resultant DMSNs-QDs as label materials have been investigated. A series of DMSNs with controllable amino/thiol group densities have been synthesized. It is demonstrated that the amino groups are beneficial for QD fluorescence preservation, owing to the amino-based surface passivation, while the thiol groups are responsible for increasing the loading capacity of QDs due to the thiol−metal coordination. The optimized DMSNs-QDs labels with an amino density of 153 μmol g −1 and a thiol density of 218 μmol g −1 displayed sufficient QD fluorescence preservation (89.4%) and high QD loading capacity (1.55 g g −1 ). Ultrasensitive detection of serum amyloid A (SAA) with a detection limit of 10 pg mL −1 with the naked eye was achieved, which is 1 order of magnitude higher than that reported in the literature. This study provides insights into the development of advanced label materials and an ultrasensitive LFIA for future bioassay applications.

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