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2D layered materials with broken inversion symmetry are being extensively pursued as  spin source layers to realize high-efficiency magnetic switching. Such low-symmetry layered systems are, however, scarce. In addition, most layered magnets with perpendicular magnetic anisotropy show a low Curie temperature. Here, the experimental observation of spin-orbit torque magnetization self-switching at room temperature in a layered polar ferromagnetic metal, Fe2.5 Co2.5 GeTe2 is reported. The spin-orbit torque is generated from the broken inversion symmetry along the c-axis of the crystal. These results provide a direct pathway toward applicable 2D spintronic devices.

The room temperature gas sensor has attracted sufficient attention due to the fact that low-power products are more suitable for practical environments. However, developing gas sensors with low detection limits remains challenging. In this paper, a room-temperature sensor was prepared by in situ growth of WO 3 nanospheres on SnO 2 inverse opal (IO) by aerosol assisted chemical vapor deposition (AACVD) method, detecting ppb level of ammonia. The WO 3 nanospheres are directly fabricated on IO, and their elemental composition, morphology and structure is characterized using XRD, SEM and TEM. The results show that WO 3 nanospheres have been prepared on SnO 2 IO successfully. It showes that the WO 3 /SnO 2 (WS) type sensor has a detection limit as low as 1 ppb at room temperature from the gas sensitivity data. In addition, the sensor's response value to 100 ppm NH 3 reached 65 %. Its excellent sensing performance depends on the distinctive morphology features of WO 3 and SnO 2. The hierarchical characteristic effectively enhances the sensing performance for NH 3. Consequently, this presents a feasible solution for fabricating the room temperature NH 3 sensor. [ABSTRACT FROM AUTHOR]

This study introduces an innovative approach for preparing gas sensors involving the formation of metal oxides from metal–organic framework materials via a two-step calcination process. A gas-sensitive material capable of detecting NH 3 at a concentration of 11 ppb at room temperature was developed using a simple and facile experimental method. Compared with materials produced in previous studies by one-step calcination, the C-doped ZnO developed in this study had a dispersed cubic porous morphology with a higher specific surface area and smaller pore size. During two-step calcination, urea acts as a structure-directing agent and increases the gas adsorption capacity of the final material. Additionally, the incorporation of urea slightly reduced the material's band gap. Further examinations confirmed the material's exceptional selectivity and long-term stability in detecting NH 3 , and response tests at 59 %, 75 %, and 85 % relative humidity indicated its tolerance to high-humidity environments. These outstanding characteristics suggest that the proposed fabrication method can produce metal-oxide materials with substantially enhanced gas-sensing performance. [Display omitted] [ABSTRACT FROM AUTHOR]

A methodology was developed for synthesizing N -acyl- N '-sulfonyl hydrazides through acyl substitution reactions between activated amides and arylsulfonyl hydrazides. Optimization of the reaction conditions revealed that using Cs₂CO₃ as a base and 1,4-dioxane as a solvent at 25 °C for 12 hours produced the highest yields. Among various amides tested, N -benzoylsuccinimide was found to be the most reactive, with reduced reactivity observed for N -mesityl-, N -tosyl-, and N -Boc-substituted tertiary benzoyl amides. Cross-reactions between a diverse range of N -benzoylsuccinimides and arylsulfonyl hydrazides successfully produced the corresponding N -acyl- N′ -sulfonyl hydrazides with yields ranging from 63% to 94%. [ABSTRACT FROM AUTHOR]

Room temperature gas sensing is crucial for practical devices used in indoor environments. Among various materials, metal oxides are commonly used for gas sensing, but their strong insulating properties limit their effectiveness at room temperature. To address this issue, many studies have explored diverse methods such as nanoparticle decoration or conductive support, etc. Here, we report the emergence of gas-sensing functionality at room temperature with improved CO gas selectivity on SnO2 nanoparticles through sequential steps by using amorphous carbon (a-C) support and PtOx decoration. The SnO2 decorated on amorphous carbon shows enhanced gas adsorption compared to inactive gas sensing on SnO2 decorated carbon support. The higher Vo site of SnO2 on a-C induces gas adsorption sites, which are related to the higher sp2 bonding caused by the large density of C defects. The ambiguous gas selectivity of SnO2/a-C is tailored by PtOx decoration, which exhibits six values of sensing responses (Rg/Ra or Ra/Rg) under CO gas at room temperature with higher selectivity. Compared to PtOx/a-C, which shows no response, the enhanced CO gas sensing functionality is attributed to the CO adsorption site on PtOx-decorated SnO2 particles. This report not only demonstrates the applicability of CO gas sensing at room temperature but also suggests a strategy for using SnO2 and carbon compositions in gas sensing devices. [ABSTRACT FROM AUTHOR]

In 2 O 3 @ZnO nanotubes were fabricated using MIL-68@ZIF-8 as a template, and then fern-like In 2 O 3 @ZnO@Pd nanotubes with unique structures were synthesized by chemical reduction. The samples were thoroughly investigated to study their composition, morphology and structure. Hydrogen (H 2) sensitization characteristics of sensor of In 2 O 3 @ZnO@Pd nanotubes with different ZnO and Pd contents were tested at room temperature (RT). The In 2 O 3 @ZnO@Pd nanotube sensor with a palladium（Pd）content of 2.0 wt% exhibits a high response (R a /R g = 270) and fast response time (t res = 32 s) and recovery time (t rec = 116 s) to 10,000 ppm H 2 at RT, as well as excellent selectivity, behaving a response nearly six times that of interfering gases. The excellent hydrogen sensing performance indicates that the fern-like In 2 O 3 @ZnO@Pd nanocomposite has good application prospects and is an excellent hydrogen-sensitive material. In this paper, In 2 O 3 @ZnO nanotubes were prepared using nanoscale MIL-68@ZIF-8 as a template to enable further optimization of morphology with smaller scales. Fern-like In 2 O 3 @ZnO@Pd nanotubes with unique structures were then synthesized by doping noble metal Pd and chemical reduction. The H 2 sensing properties of fern-like In 2 O 3 @ZnO@Pd nanotubes to different concentrations of hydrogen were investigated by varying the contents of zinc oxide (ZnO) and Pd elements. The In3Zn–Pd 2 sample showed excellent sensitivity and selectivity to 10,000 ppm H 2 with a maximum response of 277.1 at RT, which was 6.6 times higher than pure In 2 O 3 @ZnO at the same temperature, and the response value was nearly six times that of the interfering gas. Moreover, the response/recovery time of the NT-Pd 2 samples was 32 and 116 s, respectively, which was substantially shorter than those of In 2 O 3 @ZnO at the same temperature (183 and 355s). [Display omitted] • Hydrogen gas sensor fabricated using fern-like In 2 O 3 @ZnO@Pd nanotubes. • The sensor detects hydrogen at room temperature providing a wider and safer range of applications. • The sensor has a high response value (277.1) and short response/recovery time (32s/116s) to hydrogen at room temperature. • The sensor has good selectivity and a response value of up to six times that of interfering gases. [ABSTRACT FROM AUTHOR]

In this study, pristine silver-doped zinc oxide (Ag–ZnO) and Plumbago zeylanica leaf extract (PZE) incorporated with Ag–ZnO, along with the additional material of cetyltrimethylammonium bromide (CTAB)-assisted Ag–ZnO nanorods, were synthesized and extensively characterized. The basic properties of the samples were studied and optimized. Gas sensing measurements were conducted, and the obtained results were thoroughly interpreted. The study includes demonstrating and examining pure Ag–ZnO, PZE-added Ag–ZnO, and CTAB-assisted Ag–ZnO. Notably, the presence of CTAB exhibited a favorable effect on the Ag–ZnO, indicating an enhanced isopropyl alcohol gas sensing response time of 20 s at 15 ppm within an ambient temperature. Additionally, improvements in selectivity and reduced sensor resistance in current (nanoampere - nA) were observed in CTAB-assisted Ag–ZnO. The sensing mechanism was investigated, focusing on the depletion layer of Ag–ZnO with the surfactant. The work emphasizes the sensing abilities of PZE-assisted Ag–ZnO and CTAB Ag–ZnO, highlighting the significance of these noble metals in systematic gas sensing applications. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) have a wide range of applications in energy storage power stations. However, thermal runaway of LIBs can lead to serious safety accidents and cause significant losses. Therefore, it is particularly important to carry out early security warning of LIBs. And H 2 is generated along with the growth of lithium dendrites, which can serve as an effective indicator for detecting LIBs before TR. In this paper, In 2 O 3 /NiO nanocomposites were prepared, and five groups of samples were systematically prepared by adjusting the molar ratio of In and Ni. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and other test methods were used to characterize the prepared nanocomposites. Through experiments, the best samples among several groups of samples were determined. When the test gas is introduced, the resistance change of this optimal sensor is the greatest, indicating the best performance, which is significantly better than pure In 2 O 3 and pure NiO samples. Furthermore, compared to other gases, this nanocomposite sensor exhibits significant selectivity towards H 2. The results show that In 2 O 3 /NiO is a promising candidate material for room temperature H 2 detection, and provide suggestions for the development of gas sensors with heterogeneous structures. [ABSTRACT FROM AUTHOR]

Detection and discrimination of volatile organic compounds (VOCs) is important to provide a more realistic assessment of their potential implication in complex environments and medical diagnostics based on volatile biomarkers. Herein, chemiresistive sensors are fabricated using stacked MoS2 nanoflakes with defects and exposed‐edge sites. The sensor is found to be extremely selective to triethylamine (TEA) over polar, non‐polar VOCs and atmospheric gases. The sensor exhibits a sensitivity of 1.72% ppm−1, fast response/recovery (19 s/39 s) to 100 ppm TEA at room temperature, low limit of detection (64 ppb), device reproducibility, humidity tolerance (RH 90%) and stability tested up to 60 days. The kinetic analysis of sensing curves reveals two discrete adsorption sites corresponding to edge and basal sites of interaction, with a higher rate constant of association and dissociation for TEA. The Density Functional Theory (DFT) studies support higher adsorption energy of TEA on MoS2 surface with respect to other volatile amines. The sensor demonstrates TEA recognition and composition estimation capability in a binary mixture of a similar class of VOCs using Machine Learning driven analysis with 95% accuracy. The ability to discriminate amines in binary mixture of other volatile amines paves the way for the advancement of next‐generation devices in the field of disease diagnosis. [ABSTRACT FROM AUTHOR]

Ta 2 O 5 /Pd hybrid microspheres were readily synthesized via a one-step thermal solution process employing a template composed of glucose carbon spheres, yielding a structure characterized by a rough and porous surface. This morphology offers an expanded contact area and increased sites for ethanol reactions of Ta 2 O 5 /Pd hybrid microspheres. At room temperature (25 °C), the Ta 2 O 5 /Pd hybrid microspheres exhibited responsiveness to ethanol concentrations ranging from 50 to 700 ppm, displaying a linear response pattern to a narrow concentration gradient of 90–120 ppm. The hybrid exhibited notable sensitivity, manifesting a response value of 5.1–100 ppm ethanol. In addition, they displayed less responsiveness to other VOCs gases, were minimally affected by humidity, and maintained gas-sensitive stability for 30 days, demonstrating excellent selectivity and long-term stability. Based on the fitting curve analysis, the material theoretically demonstrated the ability to detect ethanol at concentrations as low as 101 ppb. Ta 2 O 5 /Pd hybrid microspheres modified by glucose carbon sphere templates and noble metal nanoparticles are promising candidates for ethanol room temperature sensing, providing new insights into the development of room temperature sensing. [ABSTRACT FROM AUTHOR]

Structural adhesives that do not require heating are in high demand in the automotive and electronics industries. However, it remains a challenge to develop robust adhesives that rapidly achieve super adhesion near ambient temperature. Herein, a room‐temperature curable, fast‐bonding, and super strong epoxy‐based structural adhesive was designed from the perspective of cross‐scale structure, which lies in threefold pivotal aspects: (i) high branching topology of glycerol carbonate‐capped polyurethane (PUGC) increases the kinetics of the ring‐opening reaction, contributing to fast crosslinking and the formation of abundant urethane and hydroxyl moieties; (ii) asynchronous crosslinking of epoxy and PUGC synergistically induces phase separation of PUGC within the epoxy resin and the resulting PUGC domains surrounded by interpenetrated shell serves to efficiently toughen the matrix; (iii) abundant dynamic hydrogen bonds including urethane and hydroxyl moieties, along with the elastomeric PUGC domains, dissipate energy of shearing force. As a result, the adhesive strength rapidly grows to 16 MPa within 4 hours, leveling off to 21 MPa after 7 hours, substantially outperforming commercial room‐temperature curable epoxy adhesives. The results of this study could advance the field of high‐performance adhesives and provide valuable insights into designing materials for efficient curing at room temperature. [ABSTRACT FROM AUTHOR]

An advanced scanning probe microscopy system enhanced with artificial intelligence (AI‐SPM) designed for self‐driving atomic‐scale measurements is presented. This system expertly identifies and manipulates atomic positions with high precision, autonomously performing tasks such as spectroscopic data acquisition and atomic adjustment. An outstanding feature of AI‐SPM is its ability to detect and adapt to surface defects, targeting or avoiding them as necessary. It is also designed to overcome typical challenges such as positional drift and tip apex atomic variations due to the thermal effects, ensuring accurate, site‐specific surface analysis. The tests under the demanding conditions of room temperature have demonstrated the robustness of the system, successfully navigating thermal drift and tip fluctuations. During these tests on the Si(111)‐(7 × 7) surface, AI‐SPM autonomously identified defect‐free regions and performed a large number of current–voltage spectroscopy measurements at different adatom sites, while autonomously compensating for thermal drift and monitoring probe health. These experiments produce extensive data sets that are critical for reliable materials characterization and demonstrate the potential of AI‐SPM to significantly improve data acquisition. The integration of AI into SPM technologies represents a step toward more effective, precise and reliable atomic‐level surface analysis, revolutionizing materials characterization methods. [ABSTRACT FROM AUTHOR]

Achieving highly selective, highly responsive detection of formaldehyde gas at ppb level at room temperature is highly challenging for air monitoring and life health observation. Therefore, in this paper, low-cost, easy-to-fabricate, highly responsive as well as highly selective Zn 2 SnO 4 /SnO 2 (ZTO/SnO 2) metal-oxide semiconductor gas sensors have been successfully prepared by using one-pot hydrothermal method. The results showed that the synergistic effect of the n-n heterojunction formed between ZTO/SnO 2 prepared by this method led to a substantial increase in the sensitivity to the target gases, and ZTO/SnO 2 -3 a higher response (291) to 100 ppm formaldehyde compared to the response values of pure samples of Zn 2 SnO 4 (20.4) and pure SnO 2 (6.99) at room temperature. In addition, the response value for formaldehyde reached about 16.5–295 times higher than that for other common hazardous gases (100 ppm) in our lives. The ZTO/SnO 2 -3 sample with 1 mol/L NaOH was homogeneous and small, exposing as much surface as possible, and the theoretical minimum detection limit was calculated to be 50 ppb. Therefore, the large specific surface area and active adsorption/interaction sites are favorable for gas sensing. This work provides an excellent way to prepare gas-sensitive characteristic sensors using NaOH to improve the surface structure. [ABSTRACT FROM AUTHOR]

A simple, one-pot synthesis of nine 3-(4-oxo-4,5-dihydro-thiazole-2-yl sulfanyl) succinate derivatives has been achieved in moderate to good yields via a three-component reaction of dialkyl acetylenedicarboxylates, phosphites, and rhodanine at room temperature conditions and a magnetically-separable Fe3O4@gly@Furfural@Co(NO3)2 nanocatalyst. The size, surface charge, superparamagnetic properties, crystalline structure, and surface functional groups of nanoparticles were characterized and carried out utilizing several techniques such as X-ray diffraction analysis (XRD), Field emission scanning electron microscopy (FESEM), and Value stream mapping (VSM). [ABSTRACT FROM AUTHOR]

Developing novel high‐temperature van der Waals ferromagnetic semiconductor materials and investigating their interface coupling effects with 2D topological semimetals are pivotal for advancing next‐generation spintronic and quantum devices. However, most van der Waals ferromagnetic semiconductors exhibit ferromagnetism only at low temperatures, limiting the proximity research on their interfaces with topological semimetals. Here, an intrinsic, van der Waals layered room‐temperature ferromagnetic semiconductor crystal, FeCr0.5Ga1.5Se4 (FCGS), is reported with a Curie temperature (TC) as high as 370 K, setting a new record for van der Waals ferromagnetic semiconductors. The saturation magnetization at low temperature (2 K) and room temperature (300 K) reaches 8.2 and 2.7 emu g−1, respectively. Furthermore, FCGS possesses a bandgap of ≈1.2 eV, which is comparable to the widely used commercial silicon. The FCGS/graphene 2D heterostructure exhibits an impeccably smooth and gapless interface, thereby inducing a robust van der Waals magnetic proximity coupling effect between FCGS and graphene. After the proximity coupling, graphene undergoes a charge carrier transition from electrons to holes, accompanied by a transition from non‐magnetic to ferromagnetic transport behavior with robust anomalous Hall effect (AHE). Notably, the van der Waals magnetic proximity‐induced AHE remains robust even up to 400 K. [ABSTRACT FROM AUTHOR]

A highly sensitive hydrogen gas sensor operating at room temperature made of macroporous silicon (MPS) coated with a thin NiO film was developed. MPS layer was shaped by electrochemical anodization on an n-type Si surface. Thereafter, p-type NiO film was deposited onto the MPS surface by electrodeposition method. The morphology of the NiO/MPS sample was characterized by scanning electron microscopy. Al electrical contacts for further measurements were deposited onto the structure NiO/MPS by evaporation technique under vacuum. Gas sensing performances were measured to various H2 concentrations ranging from 122 to 1342 ppm at room temperature. The results showed that the electrical behaviour of synthesized NiO/MPS sensor is similar to that of a diode, which can be used to detect H2 gas at low concentrations, which reveals high sensitivity, fast response and recovery times working at room temperature. [ABSTRACT FROM AUTHOR]

Experiments to measure a single molecule/particle, i.e., an individual molecule/particle, at room temperature or under physiological conditions without immobilization—for example, on a surface or without significant hydrodynamic flow—have so far failed. This failure has given impetus to the underlying theory of Brownian molecular motion towards its stochastics due to diffusion. Quantifying the thermodynamic jitter of molecules/particles inspires many and forms the theoretical basis of single-molecule/single-particle biophysics and biochemistry. For the first time, our simulation results for a live cell (cytoplasm) show that the tracks of individual single molecules are localized in Brownian motion, while there is fanning out in fractal diffusion (anomalous diffusion). [ABSTRACT FROM AUTHOR]

In this paper, a room-temperature NO2 sensor based on a polyaniline (PANI)/black phosphorus (BP) composite material was proposed to solve the power consumption problem of traditional metal-oxide sensors operating at high temperatures. PANI was synthesized by chemical oxidative polymerization, whereas BP was synthesized by low-pressure mineralization. The PANI/BP composite materials were prepared via ultrasonic exfoliation and mixing. Various characterization techniques, including scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS), confirmed the successful preparation of the PANI/BP composites and their excellent structural properties. The sensor demonstrated outstanding gas sensitivity in the NO2 concentration range of 2–60 ppm. In particular, the sensor showed a response exceeding 2200% at 60 ppm NO2 concentration when using a 1:1 mass ratio of PANI to BP in the composite material. [ABSTRACT FROM AUTHOR]

High-performance and room-temperature gas sensors are ideal for industrial production and environmental detection. Enhancing gas-detection capability by the use of highly conductive MXene in conjunction with metal oxide materials is a potential approach. In this work, we have prepared a gas-sensing composite device based on SnO2/V2CTx nanocomposites, which can be used to detect the concentration of SO2 gas at room temperature (~ 20 ℃). This paper modified two-dimensional (2D) V2CTx MXene with SnO2 nanoparticles by electrostatic binding method to synthesize SnO2/V2CTx composite nanomaterials. The experimental results show that at room temperature, the addition of SnO2 nanoparticles can markedly improve the gas-sensing response (from 66 to 83%) characteristics of pure V2CTx to SO2. The gas sensitivity of SnO2/V2CTx MXene nanocomposites can reach 83%, and its response/recovery time is 98 s/81 s under 10 ppm SO2. The gas-sensing composite devices made of SnO2/V2CTx composite nanomaterials also show good selectivity and application prospects. [ABSTRACT FROM AUTHOR]

Abstract Ex vivo human skin models are valuable tools in skin research due to their physiological relevance. Traditionally, standard cultivation is performed in a cell culture incubator with a defined temperature of 37 °C and a specific atmosphere enriched with CO2 to ensure media stability. Maintaining the model under these specific conditions limits its flexibility in assessing exposures to which the skin is exposed to in daily life, for example changes in atmospheric compositions. In this study we demonstrated that the foreskin-derived skin model can be successfully cultured at room temperature outside a CO2 incubator using a CO2-independent, serum-free media. Over a cultivation period of three days, the integrity of the tissue and the preservation of immune cells is well maintained, indicating the model’s stability and resilience under the given conditions. Exposing our Medical University of Graz – human Organotypic Skin Explant Culture (MUG-hOSEC) model to cytotoxic and inflammatory stimuli results in responses analyzable within the supernatant. Besides the common analysis of released proteins upon treatment, such as cytokines and enzymes, we have included extracellular vesicle to obtain a more comprehensive picture of cell communication.

This study reports a hydrotropic activity for synthesizing 1H-pyrazolo[1,2-b]phthalazine-5,10-dione through one pot four component aldehyde condensation, malononitrile, phthalic anhydride, and hydrazine hydrate. The simple and green hydrotropic synthetic approach offers numerous advantages such as non-toxic, inexpensive, mild reaction conditions, avoidance of harmful solvents, shorter reaction time, an excellent yield of products, simple workup, Chromatography-free, and eco-friendly. 1H-NMR confirmed all the synthesized compounds. [ABSTRACT FROM AUTHOR]

Abstract Wastewater treatment is inevitably required to alleviate the pollution of water resources by various contaminants such as antibiotics. MOFs are novel materials with photocatalytic activities. In this study, sonophotocatalytic degradation of tetracycline (TC) by the Cerium-based MOF (Ce-MOF) is optimized by modification of its synthesis route. Ce-MOF synthesis by room temperature (RT), hydrothermal (HT), and sonochemical synthesis (SC) are studied. TC degradation experiments revealed the superiority of SC synthesis. The interplay of main synthesis parameters, namely, initial ligand concentration, ultrasound (US) power and time on sonophotocatalytic activity of Ce-MOF, were investigated by response surface methodology model (RSM) utilizing the central composite experimental design (CCD). The optimum SC synthesis conditions are an initial ligand concentration of 8.4 mmol/L, a sonication power of 50 amplitude, and a US time of 60 min. The optimally synthesized Ce-MOF was characterized by infrared spectroscopy, FTIR, XRD, FE-SEM, TEM, zeta potential analysis, diffuse reflectance spectroscopy, particle size analysis, Mott-Schottky analysis, photocurrent analysis, electrochemical impedance spectra, and photoluminescence spectroscopy. The findings indicate that the removal efficiency of TC can reach up to 81.75% within 120 min in an aqueous solution containing an initial TC concentration of 120 ppm and 1 g/L Ce-MOF at pH of 7. Mineralization efficiency of the process is 71% according to COD measurements. The Ce-MOF catalyst retained its chemical stability and remained active upon TC degradation which makes it a promising candidate for wastewater treatment.

Electron spin qubits are becoming an important research direction in the field of quantum computing and information storage. However, the quantum decoherence has seriously hindered the development of this field. So far, few qubits exhibit long phase memory time (Tm), and even fewer qubits that can reach room temperature. Some reports show that the coherence times of radicals are generally long, so radicals may be the preferred spin carriers for qubits. Here, we demonstrate the qubit properties of a photogenerated radical (1 a) based on 2,4,6‐Tri(4‐pyridyl)‐1,3,5‐triazine (tpt, 1). More importantly, the photogenerated radical is a spin self‐diluting complex, which the dilution is generally used in the investigation of qubits to reduce the interference of environment on qubits in order to overcome the decoherence of qubits. It is surprised that radical tpt has a stable Tm=1.1 μs above 20 K, even keep it to room temperature. In addition, the tpt‐film prepared by the vacuum evaporation is significantly increase the T1 and Tm at low temperature. [ABSTRACT FROM AUTHOR]

Flash sintering has been applied to various ceramics since it was first reported. However, the flash sintering of lead zirconate titanate (PZT) at room temperature has not been accomplished. In this study, flash sintering of PZT piezoelectric ceramics at room temperature was realised for the first time. Subsequent to surface treatment in a low-pressure environment, the sample was flash-sintered at a high voltage in air. The sample became dense rapidly during sintering. The results showed that after 300 s of sintering, the flash-sintered samples had a high density (98.1%) and d 33 values (273 pC/N). The d 33 is the highest compared with flash sintering of PZT through the furnace temperature of several hundred degree Celsius. Owing to the extremely short sintering time and the absence of heating devices, this method can greatly reduce energy consumption and lead to volatilisation, providing a new method for the rapid preparation of piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

Global contraction of biodiversity pushed most members of Felidae into threatened or endangered list except the domestic cat (Felis catus) thence preferred as the best model for conservation studies. One of the emerging conservation strategies is vitrification of ovarian tissue which is field-friendly but not yet standardized. Thus, our main goal was to establish a suitable vitrification protocol for feline ovarian tissue in field condition. Feline ovarian tissue fragments were punched with biopsy punch (1.5 mm diameter) and divided into 4 groups. Group 1 was fresh control (Fr), while the other three were exposed to 3 vitrification protocols (VIT_CT, VIT_RT1 and VIT_RT2). VIT_CT involved two step equilibrations in solutions containing dimethyl sulfoxide (DMSO) and ethylene glycol (EG) for 10 min each at 4 °C. VIT_RT1 involved three step equilibration in solutions containing DMSO, EG, polyvinylpyrrolidone and sucrose for 14 min in total at room temperature, while in VIT_RT2 all conditions remained the same as in VIT_RT1 except equilibration timing which was reduced by half. After vitrification and warming, fragments were morphologically evaluated and then cultured for six days. Subsequently, follicular morphology, cellular proliferation (expression of Ki-67, MCM-7) and apoptosis (expression of caspase-3) were evaluated, and data obtained were analysed using generalised linear mixed model and chi square tests. Proportions of intact follicles were higher in Fr (P = 0.0001) and VIT_RT2 (P = 0.0383) in comparison to the other protocols both post warming and after the six-day culture. Generally, most follicles remained at primordial state which was confirmed by the low expression of Ki-67, MCM-7 markers. In conclusion, VIT_RT2 protocol, which has lower equilibration time at room temperature has proven superior thus recommended for vitrification of feline ovarian tissue. • Domestic cat ovarian tissue vitrification protocol as a model for endangered felids. • Manifold cryoprotectants in vitrification media produce better post-warm integrity. • Lower equilibration time at room temperature ensures better tissue morphology. [ABSTRACT FROM AUTHOR]

In this study, magnesium ammonium phosphate cement (MAPC) was prepared with different dosages of silica fume. The physical properties of MAPC were tested and its high-temperature properties were investigated in detail. The results showed that the addition of silica fume decreased the fluidity and setting time of MAPC. The results also showed that the addition of silica fume was beneficial to improving the resistance of MAPC to high temperatures. After exposure to high temperatures (200°C, 600°C, 800°C, 1,000°C, and 1,200°C), the flexural strength of MAPC reached its maximum when the additional level of silica fume was 20%. At 20°C, struvite (MgNH4PO4·6H2O) was detected as the main hydration product in MAPC. Heating of MAPC to 800°C resulted in the transformation of MgNH4PO4·6H2O to anhydrous magnesium orthophosphate [ Mg3(PO4)2 ]. After exposure to ≥1,000°C , the sintering of Mg3(PO4)2 occurred, and meanwhile forsterite (Mg2SiO4) was identified in the X-ray diffraction (XRD) pattern. After adding silica fume, more Mg2SiO4 with good thermal stability was formed, which made MAPC with better resistance to high temperatures. [ABSTRACT FROM AUTHOR]

Advances in structural biology have relied heavily on synchrotron cryo‐crystallography and cryogenic electron microscopy to elucidate biological processes and for drug discovery. However, disparities between cryogenic and room‐temperature (RT) crystal structures pose challenges. Here, Cryo2RT, a high‐throughput RT data‐collection method from cryo‐cooled crystals that leverages the cryo‐crystallography workflow, is introduced. Tested on endothiapepsin crystals with four soaked fragments, thaumatin and SARS‐CoV‐2 3CLpro, Cryo2RT reveals unique ligand‐binding poses, offers a comparable throughput to cryo‐crystallography and eases the exploration of structural dynamics at various temperatures. [ABSTRACT FROM AUTHOR]

Herein, an apposite and straightforward methodology has been established for the synthesis of 4,5-dihydro-1H-pyrazole and its derivatives by using Chalcones and Hydrazines as substrates in EtOH under 20W CFL irradiation at room temperature. The distinctive trait of this protocol is the utilization of an efficient, green, highly water soluble organophotoredox catalyst "Rhodamine B", a simple red xanthene dye, to create C–N bonds via formation of free radicals and eventually terminating with intramolecular cyclization. Short reaction time, environmentally benign approach, cost effectiveness, feasibility and adaptability with respect to a wide range of substrates and good to excellent yield of the product supplements the synthesis. [ABSTRACT FROM AUTHOR]

Wastewater treatment is inevitably required to alleviate the pollution of water resources by various contaminants such as antibiotics. MOFs are novel materials with photocatalytic activities. In this study, sonophotocatalytic degradation of tetracycline (TC) by the Cerium-based MOF (Ce-MOF) is optimized by modification of its synthesis route. Ce-MOF synthesis by room temperature (RT), hydrothermal (HT), and sonochemical synthesis (SC) are studied. TC degradation experiments revealed the superiority of SC synthesis. The interplay of main synthesis parameters, namely, initial ligand concentration, ultrasound (US) power and time on sonophotocatalytic activity of Ce-MOF, were investigated by response surface methodology model (RSM) utilizing the central composite experimental design (CCD). The optimum SC synthesis conditions are an initial ligand concentration of 8.4 mmol/L, a sonication power of 50 amplitude, and a US time of 60 min. The optimally synthesized Ce-MOF was characterized by infrared spectroscopy, FTIR, XRD, FE-SEM, TEM, zeta potential analysis, diffuse reflectance spectroscopy, particle size analysis, Mott-Schottky analysis, photocurrent analysis, electrochemical impedance spectra, and photoluminescence spectroscopy. The findings indicate that the removal efficiency of TC can reach up to 81.75% within 120 min in an aqueous solution containing an initial TC concentration of 120 ppm and 1 g/L Ce-MOF at pH of 7. Mineralization efficiency of the process is 71% according to COD measurements. The Ce-MOF catalyst retained its chemical stability and remained active upon TC degradation which makes it a promising candidate for wastewater treatment. [ABSTRACT FROM AUTHOR]

Monitoring halitosis indirectly by detecting H2S biomarkers with gas sensors is an emerging technique that holds great promise. However, developing H2S sensors with exceptional selectivity and sensitivity, as well as a detection limit in the ppb range, remains a significant technological challenge. To address these issues, we have fabricated amperometric H2S gas sensors utilizing modified Fe-N-C catalysts as electrodes. The modified Fe-N-C catalyst obtained by heat treatment of ammonium chloride salt exhibits a higher specific surface area, improved ORR catalytic performance, and excellent stability in acidic environments, which enhance the sensitivity and durability of amperometric H2S sensors. The amperometric sensors demonstrate a sensitivity of up to 502.0 nA ppm-1 for H2S and exhibit rapid response time with only 22.5 s for response and 9.0 s for recovery time toward 3 ppm of H2S. Moreover, they display good sensitivity (approximately 1506.0 nA at 3 ppm of H2S) and achieve a low limit of detection (LOD) of around 0.01 ppm. Additionally, the sensors exhibit excellent selectivity while being capable of detecting changes in trace amounts of H2S concentration within an exhaled breath environment. Our study presents experimental evidence demonstrating the successful detection of H2S in exhaled breath using amperometric sensors with modified Fe-N-C electrodes. [ABSTRACT FROM AUTHOR]

The development and manufacture of room-temperature NH3 respiratory gas sensors are particularly important in the medical field. However, current NH3 sensors either lack sensitivity or have slow response and recovery. Herein, in situ growth of TiO2 nanosheet on the layered amorphous C derived from oxidation of Ti3C2Tx by a hydrothermal method is proposed. The resultant gas sensing performance showed that the TiO2-C-2 (hydrothermal reactor for 12 h) specimen exhibited a high gas response value (10.3) and short response and recovery times (69 and 82 s, respectively) to 100 ppm of NH3 at room temperature. In the UV light environment, gas sensitivity is further improved (from 10.3 to 14.2 for 100 ppm of NH3 response value) and response and recovery times are reduced from 69 and 82 s to 50 and 60 s, respectively. Finally, selective adsorption of NH3 was characterized by density functional theory (DFT). This study confirms that the in situ growth of a TiO2 nanosheet on the layered amorphous C for gas-sensitive detection is expected to be a strategy. [ABSTRACT FROM AUTHOR]

The room temperature metal‐free cascade electrophilic addition/cyclization/oxidation reactions of (3‐phenoxyprop‐1‐yn‐1‐yl)benzenes to divergently synthesize various brominated benzopyran derivatives (3‐bromo‐2H‐chromenes, 3‐bromo‐2H‐chromen‐2‐ols and 3‐bromo coumarins) by tuning the amount of Br2 and H2O have been developed. The method exhibited high selectivity, mild reaction conditions, broad substrate scope, high efficiency, and the applicability for derivatization of the brominated products. The importance of the strategies provides a great advantage for selective synthesis of brominated benzopyran derivatives. [ABSTRACT FROM AUTHOR]

[Display omitted] • Room temperature and ultrafast synthesis of sulfur quantum dots (SQDs) is presented. • The conversion of elemental sulfur to fluorescent SQDs can be completed in 10 min. • The prepared SQDs have a photoluminescence quantum yield as high as 23.6%. • The utilization of SQDs to sensitively detect tetracycline and Ca2+ ions is reported. • A sensitive logic gate sensor based on SQDs is constructed. The direct and rapid conversion of abundant and cheap elemental sulfur into fluorescent sulfur quantum dots (SQDs) at room temperature is a critical and urgent challenge. Conventional synthesis methods require high temperatures, high pressures, or specific atmospheric conditions, making them complex and impractical for real applications. Herein, we propose a simple method for synthesizing SQDs simply by adding H 2 O 2 to an elemental sulfur-ethylenediamine (S-EDA) solution at room temperature. Remarkably, within a mere 10 min, SQDs with a photoluminescence quantum yield of 23.6 % can be obtained without the need for additional steps. A comprehensive analysis of the mechanism has demonstrated that H 2 O 2 is capable of converting S x 2− ions generated in the S-EDA solution into zero-valent sulfur atoms through oxidation. The obtained SQDs can be utilized as a fluorescent probe for detection of tetracycline (TC) and Ca2+ ions with the limit of detection (LOD) of 0.137 μM and 0.386 μM respectively. Moreover, we have developed a sensitive logic gate sensor based on SQDs, harnessing the activated cascade effect to create an intelligent probe for monitoring trace levels of TC and Ca2+ ions. This paper not only presents a viable approach for ultrafast and scalable synthesis of SQDs at room temperature, but also contributes to the efficient utilization of elemental sulfur resources. [ABSTRACT FROM AUTHOR]

Nitrogen dioxide (NO2) is a major pollutant that poses significant risks to sustainable human life. As a result, a growing focus has been placed on the development of highly selective and sensitive gas sensors for NO2. Traditional cutting-edge non-organic NO2 gas detectors often necessitate stringent production conditions and potentially harmful materials, which are not environmentally friendly, and these shortcomings have limited their widespread practical use. To overcome these challenges, we synthesized self-assembled peptide nanotubes (SPNTs) through a molecular self-assembly process. The SPNTs were then combined with SnO2 in varying proportions to construct NO2 gas sensors. The design of this sensor ensured efficient electron transfer and leverage the extensive surface area of the SPNTs for enhanced gas adsorption and the effective dispersion of SnO2 nanoparticles. Notably, the performance of the sensor, including its sensitivity, response time, and recovery rate, along with a lower detection threshold, could be finely tuned by varying the SPNTs content. This approach illustrated the potential of bioinspired methodologies, using peptide self-assemblies, to develop integrated sensors for pollutant detection, providing a significant development in environmentally conscious sensor technology. [ABSTRACT FROM AUTHOR]

Lipids play numerous pivotal physiological roles in mammalian reproduction, being indispensable for oocyte competence acquisition and post-fertilization embryonic development. Profiling lipids in minute samples, such as oocytes, presents challenges but has been accomplished through mass spectrometry technologies like Multiple Reaction Monitoring (MRM) profiling. With the dual objectives of simplifying workflow and examining the influence of preanalytical conditions, we assessed whether transportation at room temperature affects the lipid profile of bovine oocytes. To this end, samples were prepared using either monophasic (methanol only) or biphasic liquid extraction protocols (Bligh & Dyer method) and transported either on dry ice or at room temperature inside sealed-vacuum packages to prevent lipid oxidation. Subsequently, employing a comprehensive method, we screened a list of 316 MRMs from 10 different lipid subclasses in oocyte lipid extracts. Principal Component Analysis (PCA) revealed similar lipid profiles concerning temperature during transportation, whereas clear differentiation among samples was observed based on the lipid extraction method. Univariate analysis indicated that the one-phase methanol extraction resulted in higher relative abundances of phospholipids, except for phosphatidylserines. Conversely, the Bligh & Dyer extraction favored the detection of neutral intracellular lipids (triacylglycerols, free fatty acids, cholesteryl esters, and acyl-carnitines). Consequently, lipid recovery was directly correlated with the polarity of lipid class and the extraction method. Regarding transportation temperature, phosphatidylethanolamine, triacylglycerol, and free fatty acids exhibited lower abundances when samples were transported at room temperature. Based on multivariate and univariate analyses, we conclude that if samples undergo the same lipid extraction protocol and are transported in the same batch at room temperature inside vacuum-sealed bags, it is feasible to analyze lipid extracts of bovine oocytes and still obtain informative lipid profiling results. [ABSTRACT FROM AUTHOR]

Ternary metal oxide SnO2/Co3O4 has attracted much attention for its excellent sensitivity and structural stability. We prepared hollow, rough, and porous SnO2/Co3O4 nanofibers using the electrostatic spinning technique in this study. These nanofibers were subsequently compounded with Ta2O5 via the solvothermal method, resulting in the successful synthesis of nanofiber-structured Ta2O5@SnO2/Co3O4 heterojunction materials with outstanding room-temperature ethanol sensing performance. The nanofiber structure of SnO2/Co3O4 significantly enhanced the interface for active oxygen adsorption on the Ta2O5 surface, thereby increasing the number of reactive sites for ethanol gas sensitivity. The Ta2O5@SnO2/Co3O4 heterojunction can detect ethanol concentrations as low as 1 ppm at room temperature, with a response value of 6.53 for 100 ppm ethanol. The theoretical detection limit of ethanol for this material can be as low as 522 ppb, as determined by curve fitting. Nanofiber-structured Ta2O5@SnO2/Co3O4 heterojunction materials exhibited comprehensive and excellent room-temperature gas-sensitive properties, suggesting that combining the morphology regulation and heterostructure can provide innovative strategies for room-temperature sensing. [ABSTRACT FROM AUTHOR]

The development of highly active, reusable catalysts for aqueous‐phase reactions is challenging. Herein, metallic nickel is encapsulated in a nitrogen‐doped carbon–silica composite (SiO2@Ni@NC) as a catalyst for the selective hydrogenation of vanillin in aqueous media. The constructed catalyst achieved 99.8% vanillin conversion and 100% 4‐hydroxymethyl‐2‐methoxyphenol selectivity at room temperature. Based on combined scanning transmission electron microscopy, X‐ray photoelectron spectroscopy, and Raman analyses, the satisfactory catalytic performance is attributed to the composite structure consisting of an active metal, carbon, and silica. The hydrophilic silica core promoted dispersion of the catalyst in aqueous media. Moreover, the external hydrophobic NC layer has multiple functions, including preventing oxidation or leaching of the internal metal, acting as a reducing agent to reduce the internal metal, regulating the active‐site microenvironment by enriching the concentrations of H2 and organic reactants, and modifying the electronic structure of the active metal via metal–support interactions. Density functional theory calculations indicated that NC facilitates vanillin adsorption and hydrogen dissociation to promote aqueous‐phase hydrogenation. This study provides an efficient strategy for constructing encapsulated Ni‐based amphiphilic catalysts to upgrade biomass‐derived compounds. [ABSTRACT FROM AUTHOR]

The abundant tunable functional groups and room-temperature sensing properties of MXenes have garnered increasing interest in the field of gas sensing. However, the majority of research has exclusively focused on the combined impact of external substances with MXenes functional groups, with limited exploration into the modulation of MXenes' intrinsic functional groups. In this work, we successfully produced molten salt-modified Ti 3 C 2 T x MXene (M-Ti 3 C 2 T x) with tunable oxygen-functionalized surfaces using the molten salt immersion method and employed it as a chemical resistive gas sensor to detect NO 2 at room temperature (RT). Using diverse analytical techniques, we propose the O−addition effect on the surface titanium atoms and the O−substitution effect on the edge carbon atoms, refining the existence form of –O functional groups as well as realizing the effective regulation of the intrinsic functional groups. With a high response (∼25.87%−100 ppm NO 2 , whose response value is five times higher than that of pristine Ti 3 C 2 T x), relatively rapid response speed (∼99 s−25 ppm NO 2), high sensitivity (∼0.29 ppm−1), low detection limits (theoretical LoD is 3.3 ppm), good selectivity and long-term stability (maintain stable within 28 days) at RT, the sensor based on M-Ti 3 C 2 T x demonstrates excellent NO 2 sensing performance. To understand the sensing mechanism, density functional theory (DFT) calculations were conducted to explore adsorption behaviors. Theoretical analysis validates that M-Ti 3 C 2 T x has a stronger adsorption capacity for NO 2 (E ad = −1.149 eV) owing to the formation of covalent bond between the –O functional group and the nitrogen atom of NO 2. The application of the molten salt can effectively modulate the intrinsic functional groups of MXenes, expanding the scope of MXenes surface modification engineering and creating new opportunities for enhancing the gas sensing capabilities of MXenes. [ABSTRACT FROM AUTHOR]

Hydrogen (H 2) sensing materials with tuned geometrical shapes and dopants may contribute to H 2 sensing performance, however, their synthetic approaches need further exploring. Here, shape-controlled nitrogen-doped carbon microfibers decorated with palladium and palladium oxide nanoparticles (Pd/PdO NPs@C/N MFs) have been prepared by combined electrospinning, annealing and chemical deposition. Typically, the C/N MFs of ∼224 nm in diameter are observed with amorphous crystallization, around which the Pd/PdO NPs (∼20 nm in diameter) are randomly decorated. Beneficially, Pd/PdO NPs@C/N MFs present high-concentration sensing toward 0.01–30 v/v% H 2 at room temperature. Theoretically, the nitrogen dopants in PVP contribute to anchoring the growth of Pd/PdO NPs, leading to stable decoration on the surface of MFs. The excellent sensing performance might be interpreted as the synergistic effect that Pd/PdO NPs@C/N MFs expose more adsorption sites, Pd adsorbs H 2 to form PdHx intermediates, PdO alters the electronic state of Pd to assist the adsorption of H 2 , and C/N MFs serve as the support and boost the electron transfer. Practically, the simulation utilizing Pd/PdO NPs@C/N MFs to detect H 2 leakage has been conducted with reliable sensing. Nitrogen-doped carbon microfibers decorated with palladium and palladium oxide nanoparticles have been developed for high-concentration hydrogen sensing. [Display omitted] • Pd/PdO NPs@C/N MFs with controlled geometric parameters are developed. • Pd/PdO NPs@C/N MFs exhibit high-concentration H 2 sensing toward 0.01–30 v/v%. • Human-computer interaction device is built to simulate detecting H 2 leakage. [ABSTRACT FROM AUTHOR]

In this study, a two-dimensional Ti3C2Tx MXene compounded with carbon nanohorn (CNH) by an electrostatic self-assembly method was proposed and then fabricated as room temperature ammonia (NH3) gas sensors. The successful preparation of the Ti3C2Tx/CNH nanocomposite has been characterized in detail. The NH3 sensing performance based on Ti3C2Tx/CNH also has been tested at room temperature. The optimal Ti3C2Tx/CNH sensor has a response value of 21.6% to 100 ppm NH3 at room temperature, which is 10 times higher than that of the pure Ti3C2Tx sensor. Furthermore, this sensor is endowed with excellent selectivity, reliable long-term stability, and reproducibility. The enhanced sensing performance is associated with the interconnected structure and the synergistic effect of Ti3C2Tx and CNH. This work provides an effective way to prepare MXene-based sensitive materials for NH3 sensors, which shows excellent NH3 detection potential at room temperature. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) of high concentration will pose a threat to ecological environment or human health, and exhaled NH3 is significant in disease monitoring and diagnosis. Thus, developing a highly sensitive gas sensor is significant to monitor NH3 concentration in complex environments. However, traditional NH3 sensors either need high working temperature, or face the challenge of poor conductivity/ sensitivity. In this work, NH3 sensors based on self‐assembled MXene membrane have been fabricated. As‐prepared sensors show a high sensitivity of 2.10 ppm−1 towards extremely low concentrations of NH3 (ppb level) at room temperature, attributed to large surface area and high conductivity. In addition, the sensors also display low detection limit (50 ppb), fast response time (41 s), good recoverability, long‐term stability (15 days) and excellent flexibility (1000 bending cycles) towards NH3. The results provide insights into the development of highly sensitive NH3 sensors for industrial or biomedical applications. [ABSTRACT FROM AUTHOR]

In this work, CdS thin films were prepared on glass substrates using the chemical bath deposition method. The samples were used as a gas sensor for NO2 in the range of 5–50 ppm and H2S in the range of 10–50 ppm. The sensor was operated at room temperature and activated by UV LED illumination of 395 nm. The morphology, optical, and electrical properties of this nanostructure were examined using scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, spectroscopic ellipsometry, UV–Vis spectroscopy and 3D optical profilometry. The films are highly sensitive to NO2 and H2S with a response of 75 and 52% at 50 ppm respectively. Furthermore, they showed good long duration stability and short response/recovery times. The sensor response to NO2 gas increases linearly with increasing gas concentration, while for H2S gas the rate of increase of the sensor response becomes greater from 20 ppm. The results obtained suggest that the developed sensor may have great application potential to detect toxic gases such as H2S and NO2 at room temperature. [ABSTRACT FROM AUTHOR]

A novel method for the synthesis of nine Schiff Bases from Formyl Coumarin at room temperature has been achieved. Novel p-tolylimino-2H-chromen-2-one derivatives are synthesized using a five-component reaction involving 4-methyl-7-substituted coumarin, dioxane, 4-formyl-7-substituted coumarin, and p-toluidine, and effective medium at 25 °C. Their molecular structure was confirmed through some spectroscopic techniques such as C, H-NMR, FT-IR, and mass spectrometry. A close look at the structure-activity relationship clearly shows the intrinsic antimicrobial activity associated with the structure of these compounds, which in some cases is reinforced by some substitutions and decreases. This study presents an efficient multicomponent protocol, which provides several advantages such as short reaction times, high yields, and easy working up this work. [ABSTRACT FROM AUTHOR]

The exceptional properties of two‐dimensional (2D) magnet materials present a novel approach to fabricate functional magnetic tunnel junctions (MTJ) by constructing full van der Waals (vdW) heterostructures with atomically sharp and clean interfaces. The exploration of vdW MTJ devices with high working temperature and adjustable functionalities holds great potential for advancing the application of 2D materials in magnetic sensing and data storage. Here, we report the observation of highly tunable room‐temperature tunneling magnetoresistance through electronic means in a full vdW Fe3GaTe2/WSe2/Fe3GaTe2 MTJ. The spin valve effect of the MTJ can be detected even with the current below 1 nA, both at low and room temperatures, yielding a tunneling magnetoresistance (TMR) of 340% at 2 K and 50% at 300 K, respectively. Importantly, the magnitude and sign of TMR can be modulated by a DC bias current, even at room temperature, a capability that was previously unrealized in full vdW MTJs. This tunable TMR arises from the contribution of energy‐dependent localized spin states in the metallic ferromagnet Fe3GaTe2 during tunnel transport when a finite electrical bias is applied. Our work offers a new perspective for designing and exploring room‐temperature tunable spintronic devices based on vdW magnet heterostructures. [ABSTRACT FROM AUTHOR]

Room temperature gas sensing is crucial for practical devices used in indoor environments. Among various materials, metal oxides are commonly used for gas sensing, but their strong insulating properties limit their effectiveness at room temperature. To address this issue, many studies have explored diverse methods such as nanoparticle decoration or conductive support, etc. Here, we report the emergence of gas-sensing functionality at room temperature with improved CO gas selectivity on SnO2 nanoparticles through sequential steps by using amorphous carbon (a-C) support and PtOx decoration. The SnO2 decorated on amorphous carbon shows enhanced gas adsorption compared to inactive gas sensing on SnO2 decorated carbon support. The higher Vo site of SnO2 on a-C induces gas adsorption sites, which are related to the higher sp2 bonding caused by the large density of C defects. The ambiguous gas selectivity of SnO2/a-C is tailored by PtOx decoration, which exhibits six values of sensing responses (Rg/Ra or Ra/Rg) under CO gas at room temperature with higher selectivity. Compared to PtOx/a-C, which shows no response, the enhanced CO gas sensing functionality is attributed to the CO adsorption site on PtOx-decorated SnO2 particles. This report not only demonstrates the applicability of CO gas sensing at room temperature but also suggests a strategy for using SnO2 and carbon compositions in gas sensing devices.

Chlorate (ClO3-) is a common water pollutant due to its gigantic scale of production, wide applications in agriculture and industry, and formation as a toxic byproduct in various water treatment processes. This work reports on the facile preparation, mechanistic elucidation, and kinetic evaluation of a bimetallic catalyst for highly active ClO3- reduction into Cl-. Under 1 atm H2 and 20 °C, PdII and RuIII were sequentially adsorbed and reduced on a powdered activated carbon support, affording Ru0-Pd0/C from scratch within only 20 min. The Pd0 particles significantly accelerated the reductive immobilization of RuIII as >55% dispersed Ru0 outside Pd0. At pH 7, Ru-Pd/C shows a substantially higher activity of ClO3- reduction (initial turnover frequency >13.9 min-1 on Ru0; rate constant at 4050 L h-1 gmetal-1) than reported catalysts (e.g., Rh/C, Ir/C, Mo-Pd/C) and the monometallic Ru/C. In particular, Ru-Pd/C accomplished the reduction of concentrated 100 mM ClO3- (turnover number > 11,970), whereas Ru/C was quickly deactivated. In the bimetallic synergy, Ru0 rapidly reduces ClO3- while Pd0 scavenges the Ru-passivating ClO2- and restores Ru0. This work demonstrates a simple and effective design for heterogeneous catalysts tailored for emerging water treatment needs.