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Nanoparticles are useful in a wide range of applications such as catalysis, imaging, and energy storage. Yao et al. developed a method for making nanoparticles with up to eight different elements (see the Perspective by Skrabalak). The method relies on shocking metal salt-covered carbon nanofibers, followed by rapid quenching. The “carbothermal shock synthesis” can be tuned to select for nanoparticle size as well. The authors successfully created PtPdRhRuCe nanoparticles to catalyze ammonia oxidation. Science , this issue p. 1489 ; see also p. 1467 Shocking metal salts dispersed on carbon nanofibers produces nanoparticles composed of up to eight metals. The controllable incorporation of multiple immiscible elements into a single nanoparticle merits untold scientific and technological potential, yet remains a challenge using conventional synthetic techniques. We present a general route for alloying up to eight dissimilar elements into single-phase solid-solution nanoparticles, referred to as high-entropy-alloy nanoparticles (HEA-NPs), by thermally shocking precursor metal salt mixtures loaded onto carbon supports [temperature ~2000 kelvin (K), 55-millisecond duration, rate of ~10 5 K per second]. We synthesized a wide range of multicomponent nanoparticles with a desired chemistry (composition), size, and phase (solid solution, phase-separated) by controlling the carbothermal shock (CTS) parameters (substrate, temperature, shock duration, and heating/cooling rate). To prove utility, we synthesized quinary HEA-NPs as ammonia oxidation catalysts with ~100% conversion and >99% nitrogen oxide selectivity over prolonged operations.

Selective conversion of methane (CH 4 ) into value-added chemicals represents a grand challenge for the efficient utilization of rising hydrocarbon sources. We report here dimeric copper centers supported on graphitic carbon nitride (denoted as Cu 2 @C 3 N 4 ) as advanced catalysts for CH 4 partial oxidation. The copper-dimer catalysts demonstrate high selectivity for partial oxidation of methane under both thermo- and photocatalytic reaction conditions, with hydrogen peroxide (H 2 O 2 ) and oxygen (O 2 ) being used as the oxidizer, respectively. In particular, the photocatalytic oxidation of CH 4 with O 2 achieves >10% conversion, and >98% selectivity toward methyl oxygenates and a mass-specific activity of 1399.3 mmol g Cu −1 h −1 . Mechanistic studies reveal that the high reactivity of Cu 2 @C 3 N 4 can be ascribed to symphonic mechanisms among the bridging oxygen, the two copper sites and the semiconducting C 3 N 4 substrate, which do not only facilitate the heterolytic scission of C-H bond, but also promotes H 2 O 2 and O 2 activation in thermo- and photocatalysis, respectively. Selective conversion of methane into value-added chemicals is a promising approach for utilization of hydrocarbon sources. Here the authors develop dimeric copper centers supported on graphitic carbon nitride (denoted as Cu 2 @C 3 N 4 ) with >10% conversion and >98% selectivity toward methyl oxygenates in both thermo- and photo- catalytic reactions.

Interfacial photoelectrochemistry at photoanodes has been extensively researched for solar energy conversion, but its application for the production of high-value-added chemical compounds in organic chemistry still presents challenges. Herein, we report photoelectrocatalytic Cl-mediated C( sp 3 )–H aminomethylation of alkanes with self-developed and reusable BiVO 4 photoanodes. The swift condensation of aniline with aldehydes, along with the decrease of the electricity input of aniline by photogenerated holes in the BiVO 4 photoanodes, work together to prevent excessive oxidation of aniline, leading to high yields of the desired product. Mechanistic experiments demonstrate that Cl - ions, as the key mediators, could be attracted to holes in the photoanodes and oxidized to form the Cl 2 . This is followed by light-promoted homolytic cleavage of Cl 2 , generating Cl radicals that efficiently abstract hydrogen atoms from hydrocarbons. This work opens an avenue for interfacial photoelectrochemical organic synthesis and demonstrates a potential method for optimizing solar energy conversion into fuels. A stable and recyclable BiVO 4 photoelectrode material was developed for the efficient Cl-mediated C( sp 3 )–H aminomethylation of hydrocarbons in a photoelectrochemical cell, which provides a promising method for efficient solar fuel conversion.

Ammonia represents a promising liquid fuel for hydrogen storage, but its large-scale application is limited by the need for precious metal ruthenium (Ru) as catalyst. Here we report on highly efficient ammonia decomposition using novel high-entropy alloy (HEA) catalysts made of earth abundant elements. Quinary CoMoFeNiCu nanoparticles are synthesized in a single solid-solution phase with robust control over the Co/Mo atomic ratio, including those ratios considered to be immiscible according to the Co-Mo bimetallic phase diagram. These HEA nanoparticles demonstrate substantially enhanced catalytic activity and stability for ammonia decomposition, with improvement factors achieving >20 versus Ru catalysts. Catalytic activity of HEA nanoparticles is robustly tunable by varying the Co/Mo ratio, allowing for the optimization of surface property to maximize the reactivity under different reaction conditions. Our work highlights the great potential of HEAs for catalyzing chemical transformation and energy conversion reactions. Alloys are important materials for catalysis but are usually limited by miscibility gaps present in their phase diagrams. Here the authors break this limitation by developing high-entropy alloy catalysts made of five earth-abundant elements and demonstrate great catalytic enhancements for ammonia decomposition.

Blood glucose monitoring is crucial for the daily management of diabetic patients. In this study, we developed a differential absorbance and photoplethysmography (PPG)-based non-invasive blood glucose measurement system (NIBGMS) using visible–near-infrared (Vis-NIR) light. Three light-emitting diodes (LEDs) (625 nm, 850 nm, and 940 nm) and three photodetectors (PDs) with different source–detector separation distances were used to detect the differential absorbance of tissues at different depths and PPG signals of the index finger. A spatiotemporal multimodal fused long short-term memory (STMF-LSTM) model was developed to improve the prediction accuracy of blood glucose levels by multimodal fusion of optical spatial information (differential absorbance and PPG signals) and glucose temporal information. The validity of the NIBGMS was preliminarily verified using multilayer perceptron (MLP), support vector regression (SVR), random forest regression (RFR), and extreme gradient boosting (XG Boost) models on datasets collected from 15 non-diabetic subjects and 3 type-2 diabetic subjects, with a total of 805 samples. Additionally, a continuous dataset consisting 272 samples from four non-diabetic subjects was used to validate the developed STMF-LSTM model. The results demonstrate that the STMF-LSTM model indicated improved prediction performance with a root mean square error (RMSE) of 0.811 mmol/L and a percentage of 100% for Parkes error grid analysis (EGA) Zone A and B in 8-fold cross validation. Therefore, the developed NIBGMS and STMF-LSTM model show potential in practical non-invasive blood glucose monitoring.

Multimetallic nanoclusters (MMNCs) offer unique and tailorable surface chemistries that hold great potential for numerous catalytic applications. The efficient exploration of this vast chemical space necessitates an accelerated discovery pipeline that supersedes traditional “trial-and-error” experimentation while guaranteeing uniform microstructures despite compositional complexity. Herein, we report the high-throughput synthesis of an extensive series of ultrafine and homogeneous alloy MMNCs, achieved by 1) a flexible compositional design by formulation in the precursor solution phase and 2) the ultrafast synthesis of alloy MMNCs using thermal shock heating (i.e., ∼1,650 K, ∼500 ms). This approach is remarkably facile and easily accessible compared to conventional vapor-phase deposition, and the particle size and structural uniformity enable comparative studies across compositionally different MMNCs. Rapid electrochemical screening is demonstrated by using a scanning droplet cell, enabling us to discover two promising electrocatalysts, which we subsequently validated using a rotating disk setup. This demonstrated high-throughput material discovery pipeline presents a paradigm for facile and accelerated exploration of MMNCs for a broad range of applications.

The stability of single-atom catalysts is critical for their practical applications. Although a high temperature can promote the bond formation between metal atoms and the substrate with an enhanced stability, it often causes atom agglomeration and is incompatible with many temperature-sensitive substrates. Here, we report using controllable high-temperature shockwaves to synthesize and stabilize single atoms at very high temperatures (1,500–2,000 K), achieved by a periodic on–off heating that features a short on state (55 ms) and a ten-times longer off state. The high temperature provides the activation energy for atom dispersion by forming thermodynamically favourable metal–defect bonds and the off-state critically ensures the overall stability, especially for the substrate. The resultant high-temperature single atoms exhibit a superior thermal stability as durable catalysts. The reported shockwave method is facile, ultrafast and universal (for example, Pt, Ru and Co single atoms, and carbon, C3N4 and TiO2 substrates), which opens a general route for single-atom manufacturing that is conventionally challenging.

While self-assembled material based inverted perovskite solar cells have surpassed power conversion efficiencies of 26%, enhancing their performance in large-area configurations remains a significant challenge. In this work, we report a self-assembled material based hole-selective layer 4-(7 H -dibenzo[ c,g ]carbazol-7-yl)phenyl)phosphonic acid, with a π-expanded conjugation. The enhanced intermolecular π–π interactions facilitate the self-assembly of 4-(7 H -dibenzo[ c,g ]carbazol-7-yl)phenyl)phosphonic acid molecules to form an ordered bilayer with a hydrophilic surface, which passivates the buried perovskite interface defect and enables high-quality and large-area perovskite preparation, while simultaneously enhancing interfacial charge extraction and transport. The certified efficiency of 4-(7H-dibenzo[c,g]carbazol-7-yl)phenyl)phosphonic acid based small-area (0.0715 cm 2 ) device is 26.39% with high stability. Furthermore, a certified efficiency of 25.21% is achieved for a 99.12 mm 2 large area device. Qu et al. report a self-assembled material with π-expanded conjugation to form hydrophilic ordered bilayer as hole selective layer for inverted perovskite solar cells. The enhanced interfacial charge extraction and transport enable certified efficiency of 26.39% and 25.21% for 7.15 mm 2 - and 99.12 mm 2 -devices, respectively.

Electrochemical CO 2 -to-ethanol conversion is challenged by sluggish C-C coupling kinetics and wide products distribution. Although Cu +  has been demonstrated to enhance multi-carbon (C 2+ ) formation, the stabilization of Cu + under reduction conditions is difficult. Here, we report a hydrogen-ethanol pretreatment strategy to obtain Cu nanoparticles covered by highly dispersed and disordered ZnO 1- x clusters. Ethanol-induced ZnO 1- x redispersion gives rise to abundant Cu + on the subsurface. The optimal catalyst delivers a 73.0% ethanol Faradaic efficiency (FE) and 86.0% total C 2+ FE at −0.9 V, with a 2.3 mmol cm −2  h −1 ethanol formation rate and single-pass ethanol yield of 18.0%. The catalyst also exhibits stability beyond 500 h, attributed to the stabilization of Cu + by the ZnO 1- x shield that requires a high energy barrier for lattice oxygen removal. In situ X-ray spectroscopy and calculations reveal a volcano relationship between Cu + ratio in Cu species and ethanol FE. Optimal Cu + density not only facilitates *OC-COH coupling but also optimizes the adsorption energy of *CH 2 CH 2 O on catalyst for ethanol electrosynthesis. Ethanol production from CO2 electroreduction is hindered by poor carbon–carbon coupling and competing ethylene formation. Here, the authors develop a ZnO1-x-shield copper catalyst that stabilizes Cu+ species and enables efficient and selective electrochemical ethanol synthesis.

Electronic biosensors for DNA detection typically utilize immobilized oligonucleotide probes on a signal transducer, which outputs an electronic signal when target molecules bind to probes. However, limitation in probe selectivity and variable levels of non-target material in complex biological samples can lead to nonspecific binding and reduced sensitivity. Here we introduce the integration of 2.8 μm paramagnetic beads with DNA fragments. We apply a custom-made microfluidic chip to detect DNA molecules bound to beads by measuring Impedance Peak Response (IPR) at multiple frequencies. Technical and analytical performance was evaluated using beads containing purified Polymerase Chain Reaction (PCR) products of different lengths (157, 300, 613 bp) with DNA concentration ranging from 0.039 amol to 7.8 fmol. Multi-frequency IPR correlated positively with DNA amounts and was used to calculate a DNA quantification score. The minimum DNA amount of a 300 bp fragment coupled on beads that could be robustly detected was 0.0039 fmol (1.54 fg or 4750 copies/bead). Additionally, our approach allowed distinguishing beads with similar molar concentration DNA fragments of different lengths. Using this impedance sensor, purified PCR products could be analyzed within ten minutes to determine DNA fragment length and quantity based on comparison to a known DNA standard.