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Visible light‐driven photocatalytic CO2 reduction (CO2RR) offers a sustainable and promising solution to environmental and energy challenges. However, the design of efficient photocatalysts is hindered by poor interface interactions in heterojunctions and a limited understanding of reaction kinetics. A modified Fe2O3 photocatalyst, M‐Fe2O3@MXene, is introduced featuring KH‐550‐modified M‐Fe2O3 hollow nanocubes coated with MXene, constructed via an electrostatic and Fe−O−Ti bonding self‐assembly method. This design achieves an unprecedented CO production rate of 240 µmol g⁻¹ h⁻¹ among non‐noble metal catalysts (8.6 folds vs Fe2O3). The Fe−O−Ti sites enhance *COOH intermediate formation and CO production through higher electron deficiency of Fe3+ and rapid charge transfer. This study offers new insights on the use of functional metal oxides and high‐quality Mxene layers to design efficient metal oxide‐based photocatalysts. Single‐layer MXene‐coated hollow Fe2O3 nanocube catalyst (M‐Fe2O3@MXene) is fabricated via an electrostatic and Fe−O−Ti bonding self‐assembly method. Experiments and theoretical calculations imply that interfacial Fe−O−Ti bonding increases the photocatalytic CO2 reduction (p‐CO2RR) activity by accelerating charge transfer and separation and regulating electronic property of Fe sites. This catalyst outperforms previous reports using Fe‐based photocatalysts with a CO production rate of 240 µmol g−1 h−1.

Implementing fast‐charging lithium‐ion batteries (LIBs) is severely hindered by the issues of Li plating and poor rate capability for conventional graphite anode. Wadsley–Roth phase TiNb2O7 is regarded as a promising anode candidate to satisfy the requirements of fast‐charging LIBs. However, the unsatisfactory electrochemical kinetics resulting from sluggish ion and electron transfer still limit its wide applications. Herein, an effective strategy is proposed to synchronously improve the ion and electron transfer of TiNb2O7 by incorporation of oxygen vacancy and N‐doped graphene matrix (TNO−x@N‐G), which is designed by combination of solution‐combustion and electrostatic self‐assembly approach. Theoretical calculations demonstrate that Li+ intercalation gives rise to the semi‐metallic characteristics of lithiated phases (LiyTNO−x), leading to the self‐accelerated electron transport. Moreover, in situ X‐ray diffraction and Raman measurements reveal the highly reversible structural evolution of the TNO−x@N‐G during cycling. Consequently, the TNO−x@N‐G delivers a higher reversible capacity of 199.0 mAh g−1 and a higher capacity retention of 86.5% than those of pristine TNO (155.8 mAh g−1, 59.4%) at 10 C after 2000 cycles. Importantly, various electrochemical devices including lithium‐ion full battery and hybrid lithium‐ion capacitor by using the TNO−x@N‐G anode exhibit excellent rate capability and cycling stability, verifying its potential in practical applications. An effective strategy is proposed to synchronously improve the ion and electron transfer of TiNb2O7 by incorporation of oxygen vacancy and N‐doped graphene matrix, which is designed by combination of solution‐combustion and electrostatic self‐assembly approach. Density functional theory calculations demonstrate that Li+ intercalation gives rise to the semi‐metallic characteristics of lithiated phases (LiyTNO−x), leading to the self‐accelerated electron transport.

Polymerization-induced self-assembly (PISA) is a powerful and versatile technique for producing colloidal dispersions of block copolymer particles with desired morphologies. Currently, PISA can be carried out in various media, over a wide range of temperatures, and using different mechanisms. This method enables the production of biodegradable objects and particles with various functionalities and stimuli sensitivity. Consequently, PISA offers a broad spectrum of potential commercial applications. The aim of this review is to provide an overview of the current state of rational synthesis of block copolymer particles with diverse morphologies using various PISA techniques and mechanisms. The discussion begins with an examination of the main thermodynamic, kinetic, and structural aspects of block copolymer micellization, followed by an exploration of the key principles of PISA in the formation of gradient and block copolymers. The review also delves into the main mechanisms of PISA implementation and the principles governing particle morphology. Finally, the potential future developments in PISA are considered.

A highly sensitive pressure-sensitive sensor based on MXene was developed using the electrostatic self-assembly method, with carbide sponges as the elastic substrate and a rational design. Specifically, CTAB was used to treat the carbide triamine sponge and conduct the electrostatic self-assembly with MXene to achieve a tightly combined conductive filler and substrate. The resulting pressure sensor showed excellent performance, with a high sensitivity of 15.05 kPa −1 under a range of 0–20 kPa, a response time of 0.1 s, and high durability under 2000 loading–unloading cycles. The minimum detection limit of the sensor was as low as 0.3 Pa, demonstrating excellent monitoring performance. Additionally, finite-element simulation analysis showed that MXene@CTAB@CMF had even better sensing performance at the same stress level. Moreover, the pressure sensor exhibited good sensing performance for various physiological signals and daily work monitoring of the human body, indicating its potential application value.

The Layer-by-Layer (LbL) method is a well-established method for the assembly of nanomaterials with controlled structure and functionality through the alternate deposition onto a template of two mutual interacting molecules, e.g., polyelectrolytes bearing opposite charge. The current development of this methodology has allowed the fabrication of a broad range of systems by assembling different types of molecules onto substrates with different chemical nature, size, or shape, resulting in numerous applications for LbL systems. In particular, the use of soft colloidal nanosurfaces, including nanogels, vesicles, liposomes, micelles, and emulsion droplets as a template for the assembly of LbL materials has undergone a significant growth in recent years due to their potential impact on the design of platforms for the encapsulation and controlled release of active molecules. This review proposes an analysis of some of the current trends on the fabrication of LbL materials using soft colloidal nanosurfaces, including liposomes, emulsion droplets, or even cells, as templates. Furthermore, some fundamental aspects related to deposition methodologies commonly used for fabricating LbL materials on colloidal templates together with the most fundamental physicochemical aspects involved in the assembly of LbL materials will also be discussed.

Developing sensitive, reliable, and robust surface-enhanced Raman spectroscopy (SERS) substrates relies heavily on fabricating a substantial number of hot spots. In this study, we present a straightforward method for creating Ag@PEI/Ag core-satellite nanocomposites. Large Ag nanospheres serve as the cores, and smaller Ag nanoparticles are electrostatically assembled around them through the introduction of polyethyleneimine (PEI). This assembly process generates numerous hot spots not only between two Ag satellites but also between the inner Ag core and Ag satellites, thanks to the sub-nm PEI interlayer. The nanocomposites exhibit great potential for SERS analysis, enabling effective sensing of various organic pollutants, such as thiram and ciprofloxacin, using a portable Raman spectrometer. Notably, these nanocomposites obtain an exceptional detection limit of as low as 10−8 M for them, which falls below the safety level set by the United States Environmental Protection Agency. Additionally, the substrates demonstrate excellent uniformity, reproducibility and storing stability. Consequently, the Ag@PEI/Ag core-satellite nanocomposites hold great promise as efficient SERS platforms for reliable and highly sensitive monitoring of food safety and environmental analysis.

Highlights The highly conductive Ti 3 C 2 T x (MXene) is introduced as a substrate for loading Bi 2 MoO 6 . The Bi 2 MoO 6 /MXene heterostructure exhibits ultra-long cycle durability and superior rate capability. Electrochemical kinetic mechanism is analyzed for the as-prepared heterostructure. Bi 2 MoO 6 is a potentially promising anode material for lithium-ion batteries (LIBs) on account of its high theoretical capacity coupled with low desertion potential. Due to low conductivity and large volume expansion/contraction during charge/discharge cycling of Bi 2 MoO 6 , effective modification is indispensable to address these issues. In this study, a plate-to-layer Bi 2 MoO 6 /Ti 3 C 2 T x (MXene) heterostructure is proposed by electrostatic assembling positive-charged Bi 2 MoO 6 nanoplates on negative-charged MXene nanosheets. MXene nanosheets in the heterostructure act as a highly conductive substrate to load and anchor the Bi 2 MoO 6 nanoplates, so as to improve electronic conductivity and structural stability. When the mass ratio of MXene is optimized to 30%, the Bi 2 MoO 6 /MXene heterostructure exhibits high specific capacities of 692 mAh g −1 at 100 mA g −1 after 200 cycles and 545.1 mAh g −1 with 99.6% coulombic efficiency at 1 A g −1 after 1000 cycles. The results provide not only a high-performance lithium storage material, but also an effective strategy that could address the intrinsic issues of various transition metal oxides by anchoring them on MXene nanosheets to form heterostructures and use as anode materials for LIBs.

pH-responsive polyamidoamine (PAMAM) dendrimers are used as well-defined building blocks to design light-switchable nano-assemblies in solution. The complex interplay between the photoresponsive di-anionic azo dye Acid Yellow 38 (AY38) and the cationic PAMAM dendrimers of different generations is presented in this study. Electrostatic self-assembly involving secondary dipole–dipole interactions provides well-defined assemblies within a broad size range (10 nm–1 μm) with various shapes. The size and shape of these assemblies were determined using dynamic and static light scattering (DLS/SLS) and small-angle neutron scattering (SANS); ζ-potential measurements were performed to elucidate the charge characteristics, revealing the effective surface charge density of the nano-objects as an important parameter in the size and shape control. UV–vis spectroscopy and isothermal titration calorimetry (ITC) were employed to investigate the interaction on a molecular level and from a thermodynamic point of view. The results show that the amount of isomerized cis dye depends on the dendrimer generation because of a photoprotective effect through electrostatics for lower generations and through dipole–dipole interactions for higher generations; as the cis dye and trans dye bind with different strength, the amount of cis dye then again encodes the charge density and thereby the particle size and shape.

MXenes, as emerging 2D sensing materials for next-generation electronics, have attracted tremendous attention owing to their extraordinary electrical conductivity, mechanical strength, and flexibility. However, challenges remain due to the weak stability in the oxygen environment and nonnegligible aggregation of layered MXenes, which severely affect the durability and sensing performances of the corresponding MXene-based pressure sensors, respectively. Here, in this work, we propose an easy-to-fabricate self-assembly strategy to prepare multilayered MXene composite films, where the first layer MXene is hydrogen-bond self-assembled on the electrospun thermoplastic urethane (TPU) fibers surface and the anti-oxidized functionalized-MXene (f-MXene) is subsequently adhered on the MXene layer by spontaneous electrostatic attraction. Remarkably, the f-MXene surface is functionalized with silanization reagents to form a hydrophobic protective layer, thus preventing the oxidation of the MXene-based pressure sensor during service. Simultaneously, the electrostatic self-assembled MXene and f-MXene successfully avoid the invalid stacking of MXene, leading to an improved pressure sensitivity. Moreover, the adopted electrospinning method can facilitate cyclic self-assembly and the formation of a hierarchical micro-nano porous structure of the multilayered f-MXene/MXene/TPU (M-fM2T) composite. The gradient pores can generate changes in the conductive pathways within a wide loading range, broadening the pressure detection range of the as-proposed multilayered f-MXene/MXene/TPU piezoresistive sensor (M-fM2TPS). Experimentally, these novel features endow our M-fM2TPS with an outstanding maximum sensitivity of 40.31 kPa−1 and an extensive sensing range of up to 120 kPa. Additionally, our M-fM2TPS exhibits excellent anti-oxidized properties for environmental stability and mechanical reliability for long-term use, which shows only ~0.8% fractional resistance changes after being placed in a natural environment for over 30 days and provides a reproducible loading–unloading pressure measurement for more than 1000 cycles. As a proof of concept, the M-fM2TPS is deployed to monitor human movements and radial artery pulse. Our anti-oxidized self-assembly strategy of multilayered MXene is expected to guide the future investigation of MXene-based advanced sensors with commercial values.

Ammonium perchlorate (AP) is a commonly used oxidant for rocket solid propellants. To control the thermal decomposition of AP, a new PEI-imidazole derivative (PEI-ICA) was synthesized. With the combination of Cu compound, the heat decomposition behavior of the AP’s composites was tuned, and the activation energy was also reduced. To explore the potential reason for the catalytic effect, a series of measurements were also carried out, which indicates the electrostatic self-assembly of PEI-ICA and its combination with Cu compound should be responsible for the different heat decomposition behavior of AP. Graphical Abstract