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Aromatic amines are important commercial chemicals, but their carcinogenicity poses a threat to humans and other organisms, making their rapid quantitative detection increasingly urgent. Here, amorphous MoO3 (a‐MoO3) monolayers with localized surface plasmon resonance (LSPR) effect in the visible region are designed for the trace detection of carcinogenic aromatic amine molecules. The hot‐electron fast decay component of a‐MoO3 decreases from 301 fs to 150 fs after absorption with methyl orange (MO) molecules, indicating the plasmon‐induced hot‐electron transfer (PIHET) process from a‐MoO3 to MO. Therefore, a‐MoO3 monolayers present high SERS performance due to the synergistic effect of electromagnetic enhancement (EM) and PIHET, proposing the EM‐PIHET synergistic mechanism in a‐MoO3. In addition, a‐MoO3 possesses higher electron delocalization and electronic state density than crystal MoO3 (c‐MoO3), which is conducive to the PIHET. The limit of detection (LOD) for o‐aminoazotoluene (o‐AAT) is 10−9 M with good uniformity, acid resistance, and thermal stability. In this work, trace detection and identification of various carcinogenic aromatic amines based on a‐MoO3 monolayers is realized, which is of great significance for reducing cancer infection rates. [ABSTRACT FROM AUTHOR]

Solar‐driven CO2 reduction and water oxidation to liquid fuels represents a promising solution to alleviate energy crisis and climate issue, but it remains a great challenge for generating CH3OH and CH3CH2OH dominated by multi‐electron transfer. Single‐cluster catalysts with super electron acceptance, accurate molecular structure, customizable electronic structure and multiple adsorption sites, have led to greater potential in catalyzing various challenging reactions. However, accurately controlling the number and arrangement of clusters on functional supports still faces great challenge. Herein, we develop a facile electrosynthesis method to uniformly disperse Wells‐Dawson‐ and Keggin‐type polyoxometalates on TiO2 nanotube arrays, resulting in a series of single‐cluster functionalized catalysts P2M18O62@TiO2 and PM12O40@TiO2 (M=Mo or W). The single polyoxometalate cluster can be distinctly identified and serves as electronic sponge to accept electrons from excited TiO2 for enhancing surface‐hole concentration and promote water oxidation. Among these samples, P2Mo18O62@TiO2‐1 exhibits the highest electron consumption rate of 1260 μmol g−1 for CO2‐to‐CH3OH conversion with H2O as the electron source, which is 11 times higher than that of isolated TiO2 nanotube arrays. This work supplied a simple synthesis method to realize the single‐dispersion of molecular cluster to enrich surface‐reaching holes on TiO2, thereby facilitating water oxidation and CO2 reduction. [ABSTRACT FROM AUTHOR]

A key challenge in efficient molecular separation is fabricating large‐scale, highly selective polymeric membranes with precise pore control at the molecular scale. Herein, a new contorted monomer 6,6′‐dihydroxy‐2,2′‐biphenyldiamine (DHBIPDA) is introduced as a building block to generate cross‐linked, ultra‐thin microporous nanofilms (sub‐10 nm) via interfacial polymerization, enabling rapid, and precise molecular nanofiltration. Using diacyl chloride (TPC) as the cross‐linker instead of trimesoyl chloride (TMC) significantly reduces the pore sizes within the membranes and achieves a narrower pore distribution due to a semi‐crystalline structure. The film structures are confirmed using comprehensive characterization techniques including wide‐angle X‐ray scattering (WAXS), X‐ray diffraction (XRD), positron annihilation lifetime spectroscopy (PALS), CO2 adsorption analysis, and molecular‐scale simulation. The DHBIPDA/TPC and DHBIPDA/TMC membranes achieve methanol permeance values of up to 16.4 and 15.1 LMH bar−1 coupled with molecular weight cutoffs (MWCOs) as low as 283 and 306 Da, respectively. The DHBIPDA/TPC membrane demonstrates both higher permeance and higher selectivity compared to its relatively disordered counterpart DHBIPDA/TMC, consistent with characterization data. The DHBIPDA‐derived membrane efficiently separates dye mixtures with similar molecular weights and enables effective recycling of organometallic homogeneous catalysts, suggesting its potential for industrial applications. [ABSTRACT FROM AUTHOR]

It is a great challenge to integrate incompatible subunits into ordered macroscopic materials with tailored functionalities. Herein, a facile modular assembly strategy is demonstrated to link incompatible colloidal nanocrystals and polymer micelles by using the phenolic resol as the “molecule glue” for the synthesis of nanocrystal‐inserted mesoporous frameworks with diverse functionalities. It is found that the uniform nanocrystals can be inserted into the mesoporous frameworks with outstanding spatial dispersity, even in the case of high incorporation density. This modular assembly route is versatile, a library of nanocrystals with diverse diameters, shapes, and compositions can be integrated into various kinds of mesoporous frameworks (carbon, carbon‐SiO2, and carbon‐TiO2 composites). Unprecedently, this strategy also allows the controllable assembly of two, even three types of nanocrystals within the mesoporous frameworks to achieve multiple functionalities. The as‐prepared nanocomposites can simultaneously exhibit catalytic, magnetic, and adsorption properties independently, and show synergistic effects for tandem catalytic applications. [ABSTRACT FROM AUTHOR]

Exploiting emissive hydrophobic nanoclusters for hydrophilic applications remains a challenge because of photoluminescence (PL) quenching during phase transfer. In addition, the mechanism underlying PL quenching remains unclear. In this study, the PL‐quenching mechanism was examined by analyzing the atomically precise structures and optical properties of a surface‐engineered Ag29 nanocluster with an all‐around‐carboxyl‐functionalized surface. Specifically, phase‐transfer‐triggered PL quenching was justified as molecular decoupling, which directed an unfixed cluster surface and weakened the radiative transition. Furthermore, emission recovery of the quenched nanoclusters was accomplished by using a supramolecular recoupling approach through the glutathione‐addition‐induced aggregation of cluster molecules, wherein the restriction of intracluster motion and intercluster rotation strengthened the radiative transition of the clusters. The results of this work offer a new perspective on structure‐emission correlations for atomically precise nanoclusters and hopefully provide insight into the fabrication of highly emissive cluster‐based nanomaterials for downstream hydrophilic applications. [ABSTRACT FROM AUTHOR]

Self‐assembly of subnanometer (sub‐1 nm) scale polyhedral building blocks can yield some superstructures with novel and interesting morphology as well as potential functionalities. However, achieving the self‐assembly of sub‐1 nm polyhedral building blocks is still a great challenge. Herein, through encapsulating the titanium‐substituted polyoxometalate (POM, K7PTi2W10O40) with tetrabutylammonium cations (TBA+), we first synthesized a sub‐1 nm rhombic dodecahedral building block by further tailoring the spatial distribution of TBA+ on the POM. Molecular dynamics (MD) simulations demonstrated the eight TBA+ cations interacted with the POM cluster and formed the sub‐1 nm rhombic dodecahedron. As a result of anisotropy, the sub‐1 nm building blocks have self‐assembled into rhombic dodecahedral POM (RD‐POM) assemblies at the microscale. Benefiting from the regular structure, Br− ions, and abundant active sites, the obtained RD‐POM assemblies exhibit excellent catalytic performance in the cycloaddition of CO2 with epoxides without co‐catalysts. This work provides a promising approach to tailor the symmetry and structure of sub‐1 nm building blocks by tuning the spatial distribution of ligands, which may shed light on the fabrication of superstructures with novel properties by self‐assembly. [ABSTRACT FROM AUTHOR]

Here, we report the synthesis of chiral selenium nanoparticles (NPs) using cysteine and the interfacial assembly strategy to generate a self‐assembled nanomembrane on a large‐scale with controllable morphology and handedness. The selenide (Se) NPs exhibited circular dichroism (CD) bands in the ultraviolet and visible region with a maximum intensity of 39.96 mdeg at 388 nm and optical anisotropy factors (g‐factors) of up to 0.0013 while a self‐assembled monolayer nanomembrane exhibited symmetrical CD approaching 72.8 mdeg at 391 nm and g‐factors up to 0.0034. Analysis showed that a photocurrent of 20.97±1.55 nA was generated by the D‐nanomembrane when irradiated under light while the L‐nanomembrane generated a photocurrent of 20.58±1.36 nA. Owing to the asymmetric intensity of the photocurrent with respect to the handedness of the nanomembrane, an ultrasensitive recognition of enantioselective kynurenine (Kyn) was achieved by the ten‐layer (10L) D‐nanomembrane exhibiting a photocurrent for L‐kynurenine (L‐Kyn) that was 8.64‐fold lower than that of D‐Kyn, with a limit of detection (LOD) of 0.0074 nM for the L‐Kyn, which was attributed to stronger affinity between L‐Kyn and D‐Se NPs. Noticeably, the chiral Se nanomembrane precisely distinguished L‐Kyn in serum and cerebrospinal fluid samples from Alzheimer's disease patients and healthy subjects. [ABSTRACT FROM AUTHOR]

Transition metal oxide (TMO) anode materials in lithium‐ion batteries (LIBs) usually suffer from serious volume expansion leading to the pulverization of structures, further giving rise to lower specific capacity and worse cycling stability. Herein, by introducing polyoxometalate (POM) clusters into TMOs and precisely controlling the amount of POMs, the MnZnCuOx‐phosphomolybdic acid hybrid sub‐1 nm nanosheets (MZC‐PMA HSNSs) anode is successfully fabricated, where the special electron rich structure of POMs is conducive to accelerating the migration of lithium ions on the anode to obtain higher specific capacity, and the non‐covalent interactions between POMs and TMOs make the HSNSs possess excellent structural and chemical stability, thus exhibiting outstanding electrochemical performance in LIBs, achieving a high reversible capacity (1157 mAh g−1 at 100 mA g−1) and an admirable long‐term cycling stability at low and high current densities. [ABSTRACT FROM AUTHOR]

For wavefront corrector (WFC) based on liquid crystal on silicon (LCoS), existing good phase change linearity and fast response are the key requirements to achieve fast and high-accuracy performance. Aiming at this, refreshing manner and period is optimised firstly to minimise the temporal phase fluctuation derived from pixels phase updating. Grey bit of applied voltage used for LCoS-WFC is also optimised to form better phase linearity and phase modulating accuracy, whether the LCoS is under over-driving method or not. After optimisation, both the phase error derived from poor phase linearity and the temporal phase fluctuation derived from improper refreshing process could be reduced by nearly one time, and the phase modulated step can be reduced to 80% of that before optimisation. This result can not only save significant LCoS design costs, but also provide full design guidance for future improvement of LCoS WFC. [ABSTRACT FROM AUTHOR]

Flexible gas sensors play an indispensable role in diverse applications spanning from environmental monitoring to portable medical electronics. Full wearable gas monitoring system requires the collaborative support of high‐performance sensors and miniaturized circuit module, whereas the realization of low power consumption and sustainable measurement is challenging. Here, a self‐powered and reusable all‐in‐one NO2 sensor is proposed by structurally and functionally coupling the sensor to the battery, with ultrahigh sensitivity (1.92%/ppb), linearity (R2 = 0.999), ultralow theoretical detection limit (0.1 ppb), and humidity immunity. This can be attributed to the regulation of the gas reaction route at the molecular level. The addition of amphiphilic zinc trifluoromethanesulfonate (Zn(OTf)2) enables the H2O‐poor inner Helmholtz layer to be constructed at the electrode–gel interface, thereby facilitating the direct charge transfer process of NO2 here. The device is then combined with a well‐designed miniaturized low‐power circuit module with signal conditioning, processing and wireless transmission functions, which can be used as wearable electronics to realize early and remote warning of gas leakage. This study demonstrates a promising way to design a self‐powered, sustainable, and flexible gas sensor with high performance and its corresponding wireless sensing system, providing new insight into the all‐in‐one system of gas detection. [ABSTRACT FROM AUTHOR]