Nanofluidic devices have been widely used for diode‐like ion transport and salinity gradients energy conversion. Emerging reverse electrodialysis (RED) nanofluidic systems based on nanochannel membrane display great superiority in salinity gradient energy harvesting. However, the imbalance between permeability and selectivity limits their practical application. Here, a new mesoporous carbon‐silica/anodized aluminum (MCS/AAO) nanofluidic device with enhanced permselectivity for temperature‐ and pH‐regulated energy generation was obtained by interfacial super‐assembly method. A maximum power density of 5.04 W m−2 is achieved, and a higher performance can be obtained by regulating temperature and pH. Theoretical calculations are further implemented to reveal the mechanism for ion rectification, ion selectivity and energy conversion. Results show that the MCS/AAO hybrid membrane has great superiority in diode‐like ion transport, temperature‐ and pH‐regulated salinity gradient energy conversion.

The rational design and controllable synthesis of hollow nanoparticles with both a mesoporous shell and an asymmetric architecture are crucially desired yet still significant challenges. In this work, a kinetics-controlled interfacial super-assembly strategy is developed, which is capable of preparing asymmetric porous and hollow carbon (APHC) nanoparticles through the precise regulation of polymerization and assembly rates of two kinds of precursors. In this method, Janus resin and silica hybrid (RSH) nanoparticles are first fabricated through the kinetics-controlled competitive nucleation and assembly of two precursors. Specifically, silica nanoparticles are initially formed, and the resin nanoparticles are subsequently formed on one side of the silica nanoparticles, followed by the co-assembly of silica and resin on the other side of the silica nanoparticles. The APHC nanoparticles are finally obtained via high-temperature carbonization of RSH nanoparticles and elimination of silica. The erratic asymmetrical, hierarchical porous and hollow structure and excellent photothermal performance under 980 nm near-infrared (NIR) light endow the APHC nanoparticles with the ability to serve as fuel-free nanomotors with NIR-light-driven propulsion. Upon illumination by NIR light, the photothermal effect of the APHC shell causes both self-thermophoresis and jet driving forces, which propel the APHC nanomotor. Furthermore, with the assistance of phase change materials, such APHC nanoparticles can be employed as smart vehicles that can achieve on-demand release of drugs with a 980 nm NIR laser. As a proof of concept, we apply this APHC-based therapeutic system in cancer treatment, which shows improved anticancer performance due to the synergy of photothermal therapy and chemotherapy. In brief, this kinetics-controlled approach may put forward new insight into the design and synthesis of functional materials with unique structures, properties, and applications by adjusting the assembly rates of multiple precursors in a reaction system.

The capture of sustainable energy from a salinity gradient, in particular, using renewable biomass-derived functional materials, has attracted significant attention. In order to convert osmotic energy to electricity, many membrane materials with nanofluidic channels have been developed. However, the high cost, complex preparation process, and low output power density still restrict the practical application of traditional membranes. Herein, we report the synthesis of highly flexible and mechanically robust nanofiber-arrays-based carbonaceous ordered mesoporous nanowires (CMWs) through a simple and straightforward softtemplating hydrothermal carbonization approach. This sequential superassembly strategy shows a high yield and great versatility in controlling the dimensions of CMWs with the aspect ratio changes from about 3 to 39. Furthermore, these CMWs can be used as novel building blocks to construct functional hybrid membranes on macroporous alumina. This nanofluidic membrane with asymmetric geometry and charge polarity exhibits low resistance and highperformance energy conversion. This work opens a solution-based route for the one-pot preparation of CMWs and functional heterostructure membranes for various applications.

Asymmetric hollow and magnetic mesoporous silica nanocomposites have great potential applications due to their unique structural-functional properties. Here, asymmetric multilayer-sandwich magnetic mesoporous silica nanobottles (MMSNBs) are presented through an interfacial super-assembly strategy. Asymmetric hollow silica nanobottles (SNBs) are first prepared, and Fe 3 O 4 nanoparticles monolayers and mesoporous silica layers are uniformly super-assembled on the surfaces of SNBs, respectively. The high Fe 3 O 4 nanoparticles loading endows MMSNBs with a high magnetization (8.5 emu g −1 ), while the mesoporous silica layers exhibit high surface area (613.4 m 2 g −1 ) and large pore size (3.6 nm). MMSNBs can be employed as a novel type of enzyme-powered nanomotors by integrating catalase (Cat-MMSNBs), which show an average speed of 7.59 µm s −1 (≈25 body lengths s −1 ) at 1.5 wt% H 2 O 2 . Accordingly, the water quality can be monitored by evaluating the movement speed of Cat-MMSNBs. Moreover, MMSNBs act as a good adsorbent for removing more than 90% of the heavy metal ions with the advantage of the mesoporous structure. In addition, the good magnetic response enables the MMSNBs with precise directional control and is conducive to recycling for repeated operation. This bottom-up interfacial super-assembly construction strategy allows for a new understanding of the rational design and synthesis of multi-functional nanomotors.

Osmotic energy existing between seawater and freshwater is a potential blue energy source that can mitigate the energy crisis and environmental pollution problems. Nanofluidic devices are widely utilized to capture this blue energy owing to their unique ionic transport properties in the nanometer scale. However, with respect to nanofluidic membrane devices, high membrane inner resistance and a low power density induced by disordered pores and thick coating as well as difficulty in manufacturing still impede their real-world applications. Here, we demonstrate an interfacial super-assembly strategy that is capable of fabricating ordered mesoporous silica/macroporous alumina (MS/AAO) framework-based nanofluidic heterostructure membranes with a thin and ordered mesoporous silica layer. The presence of a mesoporous silica layer with abundant silanol and a high specific surface area endows the heterostructure membrane with a low membrane inner resistance of about 7 KΩ, excellent ion selectivity, and osmotic energy conversion ability. The power density can reach up to 4.50 W/m2 by mixing artificial seawater and river water through the membrane, which is 20 times higher than that of the conventional 2D nanofluidic membrane, and outperforms about 30% compared to other 3D porous membranes. More intriguingly, the interesting pH-sensitive osmotic energy conversion property of the MS/AAO membrane is subsequently recognized, which can realize a higher power density even in acidic or alkaline wastewater, expanding the application range, especially in practical applications. This work presents a valuable paradigm for the use of mesoporous materials in nanofluidic devices and provides a way for large-scale production of nanofluidic devices.

Ligand-mediated interface control has been broadly applied as a powerful tool in constructing sophisticated nanocomposites. However, the resultant morphologies are usually limited to solid structures. Now, a facile spatially controllable ligand-mediated superassembly strategy is explored to construct monodispersed, asymmetric, hollow, open Au-silica (SiO2) nanotadpoles (AHOASTs). By manipulating the spatial density of ligands, the degree of diffusion of silica can be precisely modulated; thus the diameters of the cavity can be continuously tuned. Due to their highly anisotropic, hollow, open morphologies, we construct a multicompartment nanocontainer with enzymes held and isolated inside the cavity. Furthermore, the resulting enzyme–AHOASTs are used as biocompatible smart H2O2-sensitive nanoswimmers and demonstrate a higher diffusion coefficient than other nanoscaled swimmers. We believe that this strategy is critical not only in designing sophisticated hollow nanosystem but also in providing great opportunities for applications in nanomaterial assembly, catalysis, sensors, and nanoreactors.

Salinity gradient energy existing in seawater and river water is a sustainable and environmentally energy resource that has drawn significant attention of researchers in the background of energy crisis. Nanochannel membrane with a unique nano‐confinement effect has been widely applied to harvest the salinity gradient energy. Here, Janus porous heterochannels constructed from 2D graphene oxide modified with polyamide (PA‐GO) and oxide array (anodic aluminum oxide, AAO) are prepared through an interfacial super‐assembly method, which can achieve oriented ion transportation. Compared with traditional nanochannels, the PA‐GO/AAO heterochannels with asymmetric charge distribution and T‐mode geometrical nanochannel structure shows directional ionic rectification features and outstanding cation selectivity. The resulting heterochannel membrane can achieve a high‐power density of up to 3.73 W m−2 between artificial seawater and river water. Furthermore, high energy conversion efficiency of 30.3% even in high salinity gradient can be obtained. These achievable results indicate that the PA‐GO/AAO heterochannels has significant potential application in salinity gradient energy harvesting.

Mechanism-switchable nanomotors are expected to exhibit high adaptability and wide applicability. Herein, for the first time, we report a flask-shaped carbon@Pt@fatty-acid nanomotor with a light-induced switch between nonionic self-diffusiophoresis and bubble propulsion. This nanomotor is fabricated through superassembly of platinum nanoparticles on the surface of carbon nanobottles, and fatty acids are infused into the cavity of carbon nanobottles to serve as a light-sensitive switch. Such a nanomotor can be propelled via catalytic decomposition of H2O2 by platinum nanoparticles, exhibiting self-diffusiophoresis with opening-forward migration. Upon 980 nm laser irradiation, the fatty acids melt due to the photothermal effect and are released from the cavity, switching the dominant operational mechanism to bubble propulsion with bottom-forward migration. Compared with self-diffusiophoresis, bubble propulsion shows higher mobility and better directionality due to the hindered self-rotation. Simulation results further reveal that the confinement effect of the cavity, which facilitates the nucleation of nanobubbles, leads to the switch to bubble propulsion. This study offers an insight into the relationship between nanostructures, fundamental nanomotor operational mechanisms, and apparent propulsion performance, as well as provides a novel strategy for the regulation of movement, which is instructive for both the design and applications of nanomotors.