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In QDSSCs, a photoanode is an important part of connecting the external circuit, providing support for the transmission of photogenerated carriers to the external circuit, and also providing an attachment site for QDs. In this study, we prepared a g-C3N4@TiO2 composite for the photoanode by a two-step process. The results show that the use of g-C3N4@TiO2 greatly increases the specific surface area of the material, effectively inhibits the "electron–hole" recombination, and optimizes the stability and catalytic performance of the photoanode. Among them, the cell equipped with the g-C3N4@TiO2 photoanode has improved performance: Jsc = 26.5 mA cm−2, PCE = 8.2%, Voc = 0.62 eV, and FF = 0.50. Based on the research in this paper, it can be seen that the g-C3N4@TiO2 composite applied to the photoanode can effectively improve the cell performance and provide a feasible idea for optimizing QDSSCs. [ABSTRACT FROM AUTHOR]

The paper reports on the synthesis, crystal structure, thermal and magnetic properties of spin crossover (SCO) salts containing the [Fe(bpp)2]2+ cation (bpp = 2,6-bis(pyrazol-3-yl)pyridine) and different rigid polycarboxylate anions, such as anthracene-9,10-dicarboxylate (ADC), benzene-1,3,5-tricarboxylate (BTC) and biphenyl-4,4′-dicarboxylate (BPDC). Compound [Fe(bpp)2](ADC)·9H2O (1) shows a porous hydrogen-bonded structure with water molecules sitting in the channels. It contains low-spin (LS) Fe2+ cations that undergo crossover to the high-spin (HS) state upon dehydration. Anhydrous 1 remains HS on cooling at low temperatures. A similar magnetic behaviour is obtained for the partially protonated BTC salt [Fe(bpp)2](HBTC)·5H2O (2), showing a spin change concomitant with dehydration to a HS phase that undergoes gradual and partial SCO on cooling, affecting 25% of the Fe2+ cations. Instead, the BPDC salt [Fe(bpp)2](BPDC)·5H2O (3) has a ground HS state in its fully hydrated form. [ABSTRACT FROM AUTHOR]

In this paper, the NO donor trans-(Cl,Cl)-[Ru(FT)Cl2(NO)]Cl (Ru–NO) was incorporated in a Pluronic F127 (PL)–chitosan (CS) biocompatible hydrogel. Two concentrations were achieved (520 and 13 μg g−1), resulting in hydrogels with sol–gel transition temperatures of around 36–38 °C, according to rheological studies. The presence of the Ru–NO complex did not significantly modify the thermal (DSC) and morphological (AFM) characteristics of the gels. For Ru–NO-embedded hydrogels, nitric oxide photorelease was evidenced at 400 nm. The quantum yield of photorelease was independent of the temperature at which the gel was maintained (25, 31, or 37 °C) and was found to be ca. 0.015. EPR as well as measurements using an electrochemical NO sensor also confirmed NO release upon light irradiation at 400 nm. [ABSTRACT FROM AUTHOR]

We present in this paper the stability of SWCNT hybrid systems with Py molecules. vdW type interactions are therefore the main interaction mechanism between encapsulated molecules and nanotubes, and the simplest model to describe these interactions is the Lennard-Jones potential. We have therefore performed energy minimization calculations on hybrid SWCNTs in a very wide range of diameters and of all chirality using the Lennard-Jones potential. The structure of the carbon nanotube is obtained from the winding of graphene on itself to form a hollow cylinder described by the pair of integers (n, m) entirely determining its structural characteristics, while the optimization of the geometry of the Py molecule is obtained by SIESTA using the exchange–correlation functional LDA. After minimisation, an approach that combines density functional theory, molecular mechanics, bond polarizability model, and spectral moment's method has been used to compute Raman spectra. Two types of vibration modes of SWCNTs attract our attention. Initially, the modifications of the modes of Py after encapsulation will be analyzed. In the following discussion, we examine how the vibrational properties of single-walled carbon nanotubes (SWCNTs) are affected by encapsulation, specifically in relation to the RBM and tangential modes. Our analysis of the Raman active modes supports the notion that the structural integrity of the SWCNTs remains intact and indicates the occurrence of a charge transfer between the Py molecules and SWCNTs. This charge transfer depends on the geometric position of Py in the SWCNT. [ABSTRACT FROM AUTHOR]

In this paper, the precursors of the target product were prepared using a simple solvothermal method. After pyrolysis of the precursors, a three-dimensional Fe/CuFe2O4@C (referred to as FCC) nanomaterial with a relief texture was successfully prepared, which was employed as a novel catalyst material for activated persulfate (referred to as PS) degradation, tetracycline (referred to as TC), in wastewater. X-ray photoelectron spectroscopy (XPS) revealed that Fe(III) and Cu(II) served as the primary active metal ions, while the formation of a surface carbon shell positively influenced electron transfer during catalytic degradation. A comprehensive investigation was conducted to assess the efficiency of FCC nanocatalysts in degrading TC under various conditions. The results demonstrated that the degradation rate of TC in the 100 min range was about 96% at concentrations of 0.2 g L−1 FCC and 1 mmol L−1 persulfate and pH 7. Quenching experiment results and EPR results consistently indicated that both free radical and non-radical pathways involved in TC degradation by FCC nanomaterials, and sulfate radicals, hydroxyl radicals, superoxide radicals and singlet oxygen were identified to be the main active substances. The degradation intermediates were analyzed by liquid mass spectrometry and toxicology. FCC, as a catalyst exhibiting high catalytic activity, demonstrates superior performance in the activated persulfate degradation of TC. The environmental risk associated with the degradation of intermediate products is significantly lower than that of TC itself. FCC holds significant potential for the degradation of antibiotics in wastewater. [ABSTRACT FROM AUTHOR]

Because of high voltage resistance and high-power density, traditional ceramic dielectrics have found extensive use in electronic and pulsed power systems. Nevertheless, their subpar energy storage capabilities pose a challenge in meeting the demands of integrated and lightweight power electronic devices. This paper employs compositional design to incorporate a Bi(Zn0.5Hf0.5)O3 (BZH) relaxation component, aiming to enhance the electrical breakdown strength or effective dielectric constant, ultimately increasing the energy storage density. The 0.90(Ba0.8Sr0.2)TiO3–0.10Bi(Zn1/2Hf1/2)O3 ceramics processed by the conventional solid-phase reaction method demonstrate a significant recoverable energy density of 4.20 J cm−3, an exceptional energy storage efficiency of 95.5%, with a 450 kV cm−1 high breakdown strength and impressive charge/discharge performance. This investigation presents a novel framework for enhancing energy storage performance in other material systems. [ABSTRACT FROM AUTHOR]

The realization of high-power and thermally frequency-stable laser diodes is always highly desirable and also a difficulty in the areas of laser diodes and their applications. One of the major factors causing a shift in lasing frequency is the temperature dependence of the band-gap of the active medium, which leads to the photon energy changing. In this paper, we propose a novel approach and mechanism to overcome the variation in band-gap with temperature. This is the utilization of a nanowire constraint on the well in a self-organized InGaAs nanowire-well-bound quantum system. By binding relatively heat-stable nanowires directly to the well in this system, the thermal change in the energy-band of the hybrid quantum system is effectively restricted. As a result, the band-gap variations are limited to <0.01 meV K−1 in a temperature range of 286–339 K for unpolarized emissions, and <0.02 meV K−1 in a temperature range of 288–313 K for transverse-electric polarized emissions. The mechanism of heat-stable band-gap formation in this hybrid quantum system is analyzed in detail. This achievement is of a great significance in some advanced fields, such as atomic clocks in quantum sensing systems and optical communications. [ABSTRACT FROM AUTHOR]

Transition metal carbides and nitrides (MXenes) with excellent properties have broad prospects in electromagnetic wave absorption (EMA). In this paper, a unidirectional freeze-casting method was utilized to design a double-layer MXene absorber with orthogonal microstructures. The perpendicular and parallel samples (associated with the unidirectional freeze-casting direction), perform their respective roles in the designed double-layer absorber. The perpendicular sample with various attenuation techniques is employed as an electromagnetic wave attenuation layer, while the parallel sample with good impedance matching conditions is utilized as an impedance matching layer. Consequently, the entire absorber exhibits favorable EMA characteristics. Upon incidence of electromagnetic waves onto the parallel terminus, it is observed that the sample measuring 4.6 mm in thickness exhibits a minimal reflection loss (RLmin) of −60.8 dB at a frequency of 6.63 GHz, with a parallel end thickness accounting for 25%. In addition, the sample with a thickness of 2.6 mm displays a noteworthy maximal effective absorption bandwidth (EAB) amounting to 9.4 GHz, given a parallel end thickness of 20%. A thorough analysis of the impedance matching conditions and electromagnetic wave attenuation mechanisms of each sample reveals that the double-layer MXene absorbers with orthogonal microstructures can significantly increase the viability of MXenes in EMA. [ABSTRACT FROM AUTHOR]

Cell migration is known to be a fundamental biological process, playing an essential role in development, homeostasis, and diseases. This paper introduces a cell tracking algorithm named HFM-Tracker (Hybrid Feature Matching Tracker) that automatically identifies cell migration behaviours in consecutive images. It combines Contour Attention (CA) and Adaptive Confusion Matrix (ACM) modules to accurately capture cell contours in each image and track the dynamic behaviors of migrating cells in the field of view. Cells are firstly located and identified via the CA module-based cell detection network, and then associated and tracked via a cell tracking algorithm employing a hybrid feature-matching strategy. This proposed HFM-Tracker exhibits superiorities in cell detection and tracking, achieving 75% in MOTA (Multiple Object Tracking Accuracy) and 65% in IDF1 (ID F1 score). It provides quantitative analysis of the cell morphology and migration features, which could further help in understanding the complicated and diverse cell migration processes. [ABSTRACT FROM AUTHOR]

This paper reports on the photodegradation of the Rh 6G dye using a g-C3N4 (g-CN) nanosheet photocatalyst under UV light irradiation. The g-C3N4 nanosheets were synthesized using a simple pyrolysis method at 450 °C for 3 h at a heating rate of 2 °C min−1. Their structural phase, functional groups, surface area, optical properties, elemental composition, and morphology were investigated via XRD, BET, UV-vis, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, energy dispersive spectroscopy, and SEM microscopy. The tri-s-triazine structure of g-C3N4 was confirmed and the crystal size was calculated to be 5 nm. g-C3N4 displayed a nanosheet morphology with a BET surface area of 8 m2 g−1. C–N stretching and s-triazine units were observed in the FTIR spectrum. The photoluminescence (PL) emission maximum at 432 nm provided band edge emission related to a band gap of 2.9 eV, and the PL lifetime was 7.6 ns, which is reasonably high for photocatalytic application. Through the C1s XPS spectrum, sp2-hybridized carbon linkages of N–C＝N in the aromatic skeleton rings, such as triazine or heptazine rings, of g-C3N4 were found. The photocatalytic characteristics of g-C3N4 were studied with the Rh-6G dye using UV light illumination. Initially, the Rh-6G dye concentration and catalyst (g-C3N4) loading were optimized for the best dye degradation at 0.01 mmol and 50 mg, respectively. The maximum efficiency of g-C3N4 was 99.6% degradation of the Rh-6G dye in 300 minutes. Lower charge-transfer resistance was found to be the reason for the enhanced photodegradation activity. The most dominant reactive species that participated in the light-activated reaction were superoxide radicals. The influence of pH on photodegradation was studied and the photocatalyst was found to perform better in an acidic pH range. In addition, g-C3N4 was structurally stable, highly recyclable, and, therefore, could be reused in many cycles of photocatalysis. [ABSTRACT FROM AUTHOR]

In this paper, we report on the development of an 'off–on' fluorescent probe for the detection of hydrogen peroxide (H2O2) and mercury ions (Hg2+) using an in situ synthesized carbon quantum dot and gum Arabic silver nanoparticle composite (CQDs@GA-Ag NPs). Electron microscopy measurement clearly shows that CQDs are attached to the surface of the GA-Ag NPs. The fluorescence intensity of the CQDs was dramatically quenched in the synthesized nanocomposite via the inner filter effect (IFE) mechanism. After adding H2O2 to the nanocomposite system, the Ag NPs got oxidized leading to the formation of Ag+ ions, and the CQDs regained their photoluminescence (PL) property. This facilitates the detection of H2O2 with an extremely low detection limit of 1.02 μM. Furthermore, the as-developed nanocomposite was also tested for the detection of Hg2+ ions, obtaining a remarkably low detection limit of 1.82 μM. The developed probe was extremely selective over a wide range of interfering ions and substances. [ABSTRACT FROM AUTHOR]

Due to their high electronegativity and small atomic radius without undesirable steric hindrance, the incorporation of fluorine atoms onto a conjugated backbone has been proven to be a very effective way to tune the energy levels of organic semiconductors. In this paper, 5-fluorobenzo[c][1,2,5]thiadizole was adopted as the electron-deficient unit, thiophene and alkylthiophene as donor units, and further, thiophene and EDOT were taken as peripheral donor units, and one D–A–D and two D–π–A–π′–D fluorinated electrochromic polymer precursors were successfully synthesized via a Stille coupling reaction, namely F-BT, F-BT-Th, and F-BT-EDOT. Due to the elongation of the π-conjugated systems of precursors with the stronger electron-donating ability of the EDOT unit, the oxidation potential of the F-BT-EDOT precursor was further reduced to 0.56 V vs. Ag/AgCl accompanied by red-shifted electronic spectra. As-electropolymerized P(F-BT-EDOT) also showed favorable redox activity and excellent redox stability (<2.33% electroactivity loss after 1000 cycles). At the same time, the optical band gap of P(F-BT-EDOT) (1.37 eV) is much lower than that of P(F-BT-Th) and P(F-BT) (1.62 eV), and a stable reversible electrochromic change from dark green to dark blue was achieved with a fast response time. In the near-infrared region, P(F-BT-EDOT) shows intriguing overall electrochromic performance with a high optical contrast of up to 33% and a coloration efficiency of 196.3 cm2 C−1 at 1100 nm. It can be seen that the introduction of a strong electron-donor EDOT unit could bring about a new breakthrough in the electrochromic performance of 5-fluorobenzo[c][1,2,5]thiadizole-based fluorinated D–A polymers and enhancement in their stability, and it is expected to be applied in near-infrared electrochromic devices. [ABSTRACT FROM AUTHOR]

Heavy metal ions have a serious effect on humans and the ecosystem. Molecular sieves have attracted significant attention in heavy metal ion adsorption with distinct microporosity and uniform pore size. In this paper, we successfully synthesized nano-sized NaA molecular sieves in the presence of an organic templating agent while aluminum isopropoxide and silica sol were used as the aluminum and silica sources. To synthesize molecular sieves of the ideal size, the anionic cation concentration and templating agent were adjusted. The findings of Cu(II) and Pb(II) adsorption on NaA molecular sieves showed that under the ideal conditions of adsorption time at 90 minutes, pH = 5, adsorption temperature at 25 °C, and starting adsorbent concentration at 100 mg g−1, the optimal adsorbing capacity could reach 230 mg g−1 and 600 mg g−1, respectively. Isotherm, kinetic, thermodynamic and reusability studies of heavy metal ion adsorption on NaA molecular sieves were carried out to investigate the adsorption kinetics. This work provides a new avenue to regulate the particle sizes of molecular sieves to enhance the adsorption capacity of heavy metal ions. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the role of excited-state hydrogen bonding in the photocatalytic carbon dioxide reduction reaction (CO2RR) utilizing Rose Bengal as a catalyst, through a combined experimental and theoretical approach. Experiments validated the successful conversion of CO2 to CO in a homogeneous aqueous solution system under light irradiation, without additional photosensitizers or sacrificial agents. Theoretically, the DFT/TDDFT calculations modeled the catalyst-reactants as a hydrogen-bonded complex (HBC), understanding the energy, hydrogen, and electron transfer mechanisms induced by excited-state hydrogen bonding. Combining the photophysical and photochemical insights revealed the complete catalytic cycle, identifying the water oxidation process as the rate-limiting step in the entire photocatalytic CO2RR process. Experimental and computational results provide molecular-level insights into the structure–activity relationships. This work enhances comprehension of the pivotal role of excited-state hydrogen bonding and holds significant reference value for enhancing the conversion efficiency in the photocatalytic CO2RR. [ABSTRACT FROM AUTHOR]

Metal halide perovskites are extensively utilized in photoluminescence and photoelectric detection, owing to their modifiable band gap, elevated quantum yield, high absorption coefficient, superior charge transport properties, versatile chemical synthesis, and cost-effective manufacturing. Among the perovskite variants, bismuth–halide perovskites have emerged as a promising lead–halide alternative, garnering increasing interest for crafting non-toxic perovskites in optoelectronic applications. Nonetheless, the rapid and straightforward production of high-quality single crystals remains a challenge. This paper introduces an enhanced antisolvent crystallization method for fabricating high-quality Cs3Bi2Br9 single crystals measuring 3 × 3 mm. These crystals exhibit a remarkably low half-peak width of the X-ray diffraction swing curve at just 0.048°, maintaining stability without phase decomposition for 180 days at room temperature under air exposure. The photodetector constructed involves an aluminum electrode deposited onto the crystal surface. Utilizing 375 nm ultraviolet light as the excitation source, the device demonstrates a swift electrical response (sensitivity: 8.41 × 102), achieving the rise and decay times of the Cs3Bi2Br9 single crystal detector of 96 and 80 milliseconds, respectively. This research holds significant promise for advancing perovskite crystal preparation and photodetection techniques, particularly in the realm of bismuth-based perovskites. [ABSTRACT FROM AUTHOR]

The development of a high-efficiency, low-cost, and environmentally friendly catalyst for formaldehyde degradation is crucial for addressing the issue of indoor formaldehyde pollution. Given that modern individuals spend over 90% of their time indoors, effectively tackling indoor formaldehyde pollution holds significant importance. Therefore, this paper proposes an efficient catalyst for formaldehyde degradation: surface modification of MoS2 by single-atom Ni, which can convert formaldehyde into harmless H2O and CO2. The DFT method is employed to systematically investigate the oxidative degradation pathways of formaldehyde on the surface of Ni-doped MoS2. The research focuses on two common oxidative degradation pathways in both the L–H mechanism and E–R mechanism. Our findings demonstrate that these four reaction paths occur spontaneously within the temperature range of 300–800 K with a reaction equilibrium constant greater than 105. Moreover, even under extreme temperature conditions (100 K), the reaction rate remains favorable. Furthermore, our findings indicate that the minimum activation energy is merely 0.91 eV and H2O and CO2 only need to overcome an energy barrier of 0.71 eV for desorption from the catalyst surface. This substantiates its potential application both in indoor environments and under extreme temperature conditions. This theoretical research provides innovative ideas and strategies for effectively oxidizing formaldehyde. [ABSTRACT FROM AUTHOR]

In this study, the distribution of oxygen-containing functional groups on graphene with vacancies and topological defects was systematically investigated using advanced computational methods and the structure models for multi-defect graphene oxides (GOs) were proposed. All potential adsorption sites were considered through an automated structure generation program to identify energetically favorable structures. Unlike the pristine graphene surface where oxygen-containing functional groups always aggregate with each other, we observed a tendency for them to preferentially adsorb near defects. Furthermore, they may also be distributed on the same side or both sides of the defective graphene. These multi-defect GOs can exhibit either metallic or semiconducting properties. Notably, upon adsorbing the same oxygen-containing functional groups onto the surface of defective graphene, their electronic characteristics become homogeneous. The coexistence of vacancy/topological defects and oxygen-containing functional groups within the graphene lattice introduces intriguing mechanical anisotropic properties to graphene, including the uncommon negative Poisson's ratio. Additionally, these materials exhibit anisotropic optical behavior, displaying heightened absorption within the infrared and visible regions compared to pristine graphene. Finally, it is found that Li atoms are adsorbed stably on the surfaces of multi-defect GOs via the formation of LinO/LimOH clusters. The research findings presented in this paper, encompassing the development of structural models for multi-defect GOs, could provide crucial insights into the properties and potential applications of graphene oxides. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a novel molecular switch paradigm that integrates spin crossover complexes with the Fano resonance effect. Specifically, by performing density-functional theory calculations, the feasibility of achieving Fano resonance using spin crossover complexes is demonstrated in our designed molecular junctions using the complex {Fe[H2B(pz)2]2[Bp(bipy)]} [pz = 1-pyrazolyl, Bp(bipy) = bis(phenylethynyl)(2,2′-bipyridine)]. It is further revealed that the Fano resonance, particularly the Fano dip, is most prominent in the junction with cobalt tips among all the schemes, together with the spin-filtering effect. Most importantly, this junction of cobalt tips is able to exhibit three distinct conductance states, which are controlled by the modulation of Fano resonance due to the spin-state transition of the complex and the applied gate voltage. Such a molecular switch paradigm holds potential for applications in logic gates, memory units, sensors, thermoelectrics, and beyond. [ABSTRACT FROM AUTHOR]

Protein–ligand binding affinity prediction plays an important role in the field of drug discovery. Existing deep learning-based approaches have significantly improved the efficiency of protein–ligand binding affinity prediction through their excellent inductive bias capability. However, these methods only focus on fragmented three-dimensional data, which truncates the integrity of pocket data, leading to the neglect of potential long-range interactions. In this paper, we propose a dual-stream framework, with amino acid sequence assisting the atomic data fusion for graph neural network (termed SadNet), to fuse both 3D atomic data and sequence data for more accurate prediction results. In detail, SadNet consists of a pocket module and a sequence module. The sequence module expands the "receptive field" of the pocket module through a mid-term virtual node fusion. To better integrate sequence-level information from the sequence module and 3D structural information from the pocket module, we incorporate structural information for each amino acid within the sequence module. Besides, to better understand the intrinsic relationship between sequences and 3D atomic information, our SadNet utilizes information stacking from both the early stage and later stage. Experimental results on publicly available benchmark datasets demonstrate the superiority of the proposed dual-stream approach over the state-of-the-art alternatives. The code of this work is available online at https://github.com/wardhong/SadNet. [ABSTRACT FROM AUTHOR]

Mechanochemical methods either under neat or liquid assisted conditions have proven to be successful in making cocrystals. In this paper we compare the outcome of cocrystallization using two different mechanochemical methods, ball milling (BM) and resonant acoustic mixing (RAM), with solution crystallization. Racemic binaphthol and benzoquinone based binary and ternary cocrystals were investigated by BM and RAM. Both mechanochemical methods were successful in making the binary and ternary cocrystals that have been observed in solid state and solution. It is shown that the type of mechanochemical force imparted to the sample is very different between BM and RAM and this in turn leads to different cocrystallization outcomes. Thus, different mechanochemical methods should not be treated as the same and care must be taken when choosing a mechanochemical method for a particular application. [ABSTRACT FROM AUTHOR]

In this paper, we propose a composite nano-microstructure comprising Ti3C2 and nanogold as a surface-enhanced Raman spectroscopy (SERS)-active substrate for the highly sensitive sensing of amine gases. The adsorption performance of Ti3C2 was tested by a quartz crystal microbalance (QCM) sensor. Excellent adsorption ability of Ti3C2 was observed for aniline, phenylenediamine, and diethylamine, with adsorption amounts exceeding 2210, 1740, and 970 ng cm−2, respectively. The synergistic effect of the electromagnetic properties of Ti3C2 and nano-Au in the Ti3C2/nano-Au composite nanostructures was verified by finite-difference time-domain simulation. Partial chemical enhancement between Ti3C2 and aniline was verified by photocurrent tests. To achieve assay specificity, mercaptoacetaldehyde (MA) was adopted as a recognition probe. The Schiff base reaction between aldehyde groups and amino groups produces the –C＝N– bond, with the Raman characteristic peak at 1635 cm−1, enabling precise amine identification with the SERS chip. To obtain the Ti3C2/nano-Au@MA SERS sensing chip, nano Au was deposited on an indium tin oxide substrate using the chronoamperometric method, followed by nano-Au aldolization modification through Au-SH interactions and the spin-coating of a Ti3C2 film layer. Due to the high affinity of Ti3C2 for amine molecules and the low SERS background signal of MA and Ti3C2, the SERS spectra could be used for ultra-sensitive detection of amines. Three amine gases, i.e. aniline, p-phenylenediamine, and diethylamine, were detected quantitatively using the intensity ratiometric method on the functionalized Ti3C2/nano-Au@MA SERS sensor chip. The detection limits were 1, 1, and 20 parts per billion, respectively. By identifying the characteristic fingerprint peaks and comparing the relative intensity of the –C＝N– characteristic peak, quantitative analysis of the components of aniline and p-phenylenediamine mixed gas was accomplished. These findings demonstrate that the Ti3C2/nano-Au@MA SERS sensor chip offers a promising approach for the detection of amine gas molecules and holds potential for applications in environmental monitoring, disease diagnosis, and chemical analysis. [ABSTRACT FROM AUTHOR]

Zeolites are a class of catalysts with specific pore structures as well as different pore sizes, which are now widely used in various shape-selective catalytic reactions. In this paper, a uniform micro/mesoporous core–shell composite HZSM-@MCM-41 comprising zeolite was successfully prepared by coating mesoporous MCM-41 shells on nanosized ZSM-5 cores using a two-step hydrothermal method. Nanoscale ZSM-5 cores with different acidity were successfully prepared by changing the Si/Al of the initial solution of pristine ZSM-5, and three different thicknesses of MCM-41 shell layers were easily encapsulated on the surface of ZSM-5 with different acidity by varying the amount of silicon source added in the secondary hydrothermal crystallization process. The synthesized series of micro-mesoporous core–shell catalysts were also applied to the catalytic fast pyrolysis in lignin. In the catalytic fast pyrolysis of lignin, the mesoporous structure promoted the transition of biomass pyrolysis intermediate to liquid products, and the acidity of the HZSM-5 core facilitated their catalytic transformation to aromatic hydrocarbons. Among all the tested catalysts, the HZ@M-80-ll catalyst with an internal Si/Al = 80 and MCM-41 shell thickness of ∼25 nm exhibited the highest production of light aromatics and phenols. [ABSTRACT FROM AUTHOR]

Chiral surfaces are an object of interest due to their application in catalysis, separation and sensors. Such surfaces can exhibit chirality on the molecular or supramolecular level. Previously, we have studied the thermodynamic features of adsorption on non-porous surfaces with supramolecular chirality. However, for their application in enantiomer separation, enantioselectivity and capacity should be greater. Porous adsorbents are promising for this purpose. In this work, the enantioselectivity of copper borophosphate LiCu2[BP2O8(OH)2] was studied. This zeotype material was obtained by hydrothermal synthesis without any source of chirality. Supramolecular chirality was achieved by spontaneous symmetry breaking via Viedma ripening. XRD and SEM were used to prove the synthesis accuracy. Enantioselectivity during adsorption was studied using the adsorption isotherms of α-pinene and limonene enantiomer analysis. The experimental isotherms were approximated by Langmuir, Dubinin–Radushkevich, Freundlich and Fowler–Guggenheim equations. The t-test was used to prove the reliability of the differences in enantiomer adsorption. The isosteric heats of adsorption were calculated from the adsorption isotherms. The data obtained have shown the ability of the LiCu2[BP2O8(OH)2] surface to recognize both α-pinene and limonene enantiomers. The molecules of α-pinenes adsorbed without pores, with the maximum enantioselectivity coefficient of 1.23 at 80 °C. Limonene molecules adsorbed in pore volume as single molecules or 1D chains. This phenomenon was proved by analysis of isosteric heats. The enantioselectivity of copper borophosphate to limonenes and α-pinenes was similar. The ability of pores with supramolecular chirality (and without molecular chirality) to recognize enantiomers was discovered in this paper for the first time. [ABSTRACT FROM AUTHOR]

The proliferation of drug-resistant bacteria and infections such as methicillin-resistant Staphylococcus aureus (MRSA) pose a serious challenge to global healthcare. Photothermal therapy (PTT) is becoming a highly effective antimicrobial method. Compared with near infrared I (NIR-I), near infrared II (NIR-II) has deeper penetration depth, less light scattering and higher maximum permissible exposure (MPE). The selection of a photothermal agent (PTA) and laser parameters is important. Three kinds of MXenes, Nb2C, Ti3C2 and V2C, were prepared in this paper, and the extinction coefficient and photothermal conversion efficiency (PCE) of NIR-I and NIR-II were compared. The extinction coefficient of Ti3C2 (26.23 L g−1 cm−1) at 808 nm was greater than those of Nb2C (24.38 L g−1 cm−1) and V2C (19.43 L g−1 cm−1). However, V2C had a higher temperature than Nb2C at 808 nm due to its high PCE (49.26%). Nb2C had a higher extinction coefficient (24.99 L g−1 cm−1) and PCE (45.55%) at 1064 nm, resulting in the highest temperature change. High extinction coefficient and high PCE are the two important factors for an excellent PTA. To reduce laser power used in the treatment, NIR-II laser and a gelation strategy for MXenes were used. The prepared Nb2C/Gel could be rapidly heated to 62 °C at a laser power of 0.112 W (lower than MPE), and the sterilization rate for MRSA was 92.48%. A NIH-3T3 cell activity study showed that the prepared Nb2C had good biocompatibility. Nb2C/Gel has excellent antibacterial properties and it is expected that a rapid, efficient and safe biological antimicrobial strategy against bacterial infections can be established using Nb2C/Gel, especially for drug-resistant bacterial infections. [ABSTRACT FROM AUTHOR]

In this paper, flame retardant composites were prepared by incorporating three flame retardants (FRs), including triphenyl phosphate (TPP), polysiloxane (PSQ) and phosphite functionalized polysiloxane (PPSQ), respectively into a polylactic acid (s/PLLA) matrix. The results indicated that the ultimate oxygen index increased from 20.6% (s/PLLA) to 22.5% (s/PLLA/TPP), 21.1% (s/PLLA/PSQ), and 23.3% (s/PLLA/PPSQ). The composites exhibited a decrease in peak heat release rate (pHRR) and prolonged peak time according to the cone calorimetry analysis. s/PLLA/PPSQ possessed the highest residual carbon content and the densest char residue with finest and smallest pores, indicating excellent flame-retardant performance. The crystallization behavior analysis revealed that the three FRs resulted in an increased crystallization rate and crystallinity. Notably, the crystallinity of s/PLLA/PPSQ increased from 25.8% in s/PLLA to 37.3%. Additionally, PSQ and PPSQ effectively enhanced the mechanical properties of composite materials. Compared to s/PLLA, the tensile strength of s/PLLA/PSQ and s/PLLA/PPSQ increased by 11.5% and 31.3% respectively, and storage modulus increased by 50.0% and 14.6%. This research demonstrated that among the three additives, PPSQ can effectively provide both flame retardancy and mechanical properties to the s/PLLA matrix, resulting in the composite with the best comprehensive performance. [ABSTRACT FROM AUTHOR]

Solvent vapor-driven soft actuators are promising devices for human-environment interaction and have gained considerable attention in recent years. To enhance the interaction with the solvents and deliver a fast response and superior sensitivity, polymer/MOF composites are promising candidates for the fabrication of solvent-driven actuators. This paper presents a multiple-solvent-driven intelligent MOF-polymer soft actuator, namely MIL-88B/PVDF asymmetric film, and compares it to analogs based on other MIL-88(Fe) series flexible MOFs. This comparison investigates the deformation-structure relationship and the solvent-driven mechanism. The deformation of the MIL-88(Fe)/PVDF composite films in response to various organic solvents has been studied, and the structure and composition of the MOF fillers and the composites were characterized by SEM, FT-IR, and XRD. Furthermore, the MIL-88B/PVDF composite, which shows ability to respond to multiple solvents and a fast deformation response to several organic solvents through the solvent swelling/adsorption of the MOF skeleton and the appropriate flexibility and group affinity from the terephthalic acid ligand, was used to fabricate an inverted opal gradient actuator composed of MIL-88B, carbon black (CB) and PVDF, namely MIL-88B/CB/PVDF. The MIL-88B/CB/PVDF film not only realizes excellent dual-responsive deformation and discoloration to methanol vapor with fast visible deformation within 1 s with a maximum crimp angle of up to 5581 (10 vol% concentration) and a wide color change range covering six viewing-angledependent high-saturation colors (red, orange, yellow, green, blue and purple) but also shows an approximate linear relationship between the maximum curl angle and the solvent concentration for three solvents (methanol, toluene and chloroform). In addition, several smart devices have also been fabricated, including methanol-driven bionic petals, a worm robot, an alertor and a LIG sensor. Therefore, such polymer/MOF soft actuators have great potential in bio-robots and this work provides a new design strategy for smart materials. [ABSTRACT FROM AUTHOR]

A volumetric bar-chart chip (V-chip) is a microfluidic device based on distance-based quantitative measurement that visualizes analyte concentration without the need for apparatus or data processing. This typically utilizes special receptors and catalysis parts that generate oxygen, so ink can be moved inside the channels, and enables instant visual quantitation of the analyte. However, the low stability of some macromolecules, the use of expensive catalysts, and difficulty in controlling the process cause inaccurate readings, and therefore, limit further development and the use of these systems. In this article, we introduced a novel approach that eliminates the use of catalysts in V-chips and provides an efficient and simple path in the design of biosensors. The product of the enzymatic reaction of urease with urea is bicarbonate, which turns into CO2 gas in an acidic environment. Therefore, the amount of gas produced is proportional to the amount of urea in the sample, and it can be quantitatively measured by visual detection from the amount of ink movement caused by CO2 gas pressure. This biosensor has a linear response range of 0 to 1000 µg ml-1 and a detection limit of 3.6 µg ml-1 in raw milk. The recovery of urea in raw milk at 100 and 400 µg ml-1 concentrations was 96.5% and 98.9%, respectively. This volumetric chip shows potential for determining urea levels in real samples without requiring additional equipment. The combination of the sensitivity and specificity of enzymatic reactions, inherent gas-generating reactions, and the processability of microchips discussed in this paper can be the basis for the comprehensive development of volumetric chips, which can create a new path for the development of efficient and cheap biosensors. [ABSTRACT FROM AUTHOR]

Automated high-throughput liquid handling operations in biolabs necessitate miniaturised and automatised equipment for effective space utilisation and system integration. This paper presents a thermal segment microwell plate control unit designed for enhanced microwell-based experimentation in liquid handling setups. The development of this device stems from the need to move towards geometry standardization and system integration of automated lab equipment. It incorporates features based on Smart Sensor and Sensor 4.0 concepts. An enzymatic activity assay is implemented with the developed device on a liquid handling station, allowing fast characterisation via a high-throughput approach. The device outperforms other comparable devices in certain metrics based on automated liquid handling requirements and addresses the needs of future biolabs in automation, especially in highthroughput screening. [ABSTRACT FROM AUTHOR]

CsPbBr3 nanoplatelets (NPLs), as some of the two-dimensional lead halide perovskites, have been intensively investigated due to their outstanding photophysical and photoelectric properties. However, there remain unclear fundamental issues on their carrier kinetics and the low-energy tail in their photoluminescence (PL) spectrum. In this paper, we synthesized CsPbBr3 NPLs with five [PbBr6]4− monolayers and performed comprehensive studies by using steady-state absorption, PL, and femtosecond transient absorption (fs-TA) spectroscopic measurements. We determined both the biexciton Auger recombination time (7 ± 2 ps) and trapped exciton lifetime (110 ± 15 ps) of the five monolayer CsPbBr3 NPLs. We also investigated the origin of the low-energy tail emission in their PL spectrum. More importantly, we found that a negative ΔA feature in the energy range of 2.45–2.55 eV appears in their fs-TA spectrum at 2, 4 and 10 ps delay times, which could help them act as a laser gain medium. The low-energy tail emission in their PL spectrum overlaps well with the negative ΔA feature in the energy range of 2.45–2.55 eV in their fs-TA spectrum at 2, 4 and 10 ps delay times. [ABSTRACT FROM AUTHOR]

The present paper investigates one of the hydrazone derivatives (BTH with a D–π–A structure) based on density functional theory. With the computation results of ground state absorption (GSA), excited-state absorption (ESA) and multi-photon absorption (MPA), the optical limiting effect observed in the experiment for the BTH molecule can be well predicted and elucidated by the MPA-ESA mechanism. The analysis of the hole–electron and the electron density differences between two transition states reveal that the main transitions involved in the GSA and ESA of BTH could be recognized as local excitation. Based on these observations, four novel hydrazone derivatives based on the BTH unit with a D1–D–Ai–π–A structure were designed to promote intramolecular charge transfer (ICT). It shows that the ICT effect is well improved by adding the D1 and Ai units. Compared with the original BTH molecule, the main bands of GSA and ESA of D1–D–Ai–π–A molecules are both red-shifted. In addition, GSA, ESA and MPA probabilities are all improved because the obvious charge transfer character results in the transition dipole moment change from localized to delocalized. Accordingly, the optical limiting effect in these hydrazone derivatives is well enhanced. These observations provide guidance for designing novel optical limiting materials based on the hydrazone derivatives. [ABSTRACT FROM AUTHOR]

In this paper, we theoretically present and numerically demonstrate an actively tunable and switchable multi-functional metamaterial based on vanadium dioxide (VO2) and graphene in the terahertz region. When VO2 is in the metallic phase, the proposed metamaterial serves as a multi-band perfect absorber, which exhibits the characteristics of insensitive polarization and robust tolerance for variations of the incidence angle. When VO2 is in the insulator phase, the proposed metamaterial acts as a polarization converter, which can simultaneously achieve perfect linear-to-linear and linear-to-circular polarization conversions. The simulation results show the cross-polarization conversion rate can reach ∼100% at the frequency region from 6.09 to 6.43 THz as well as 8.15 THz. Moreover, the ellipticity of linear-to-circular polarization conversion reaches ±1 at frequencies of 5.75 and 8.34 THz, respectively, which means the linear polarization waves can be completely converted into circular polarization waves. The proposed metamaterial provides new insight for the design of optoelectronic devices with multi-functionality in the terahertz region. [ABSTRACT FROM AUTHOR]

As a significant reactive oxygen species (ROS), hypochlorous acid (HClO) plays a key role in the human immune system, ensuring the normal function of the organism. However, abnormal HClO levels have been linked to immune system disorders, neurodegenerative damage, and cancer. Therefore, rapid, and sensitive monitoring of HClO is important for the diagnosis of certain diseases. Here, we designed a probe XL for the detection of HClO in living cells, which is a mixture of phenothiazine and semi-cyanine. The probe XL is highly sensitive, selective and has an ultra-fast (<10 seconds) response to HClO in solution. The detection limit of probe XL for HClO was as low as 31 nM, and we also successfully used the test paper prepared with probe XL for the colorimetric fluorescence detection of HClO in real water samples. In addition, probe XL showed good response to both endogenous and exogenous HClO in cells. Finally, we successfully used probe XL for imaging HClO in zebrafish. [ABSTRACT FROM AUTHOR]

In this paper, three-dimensional TiO2 nanoflowers (NFs) were prepared by a facile hydrothermal method, and Ag3PO4 was grown in situ following alkali treatment to design and synthesize a Ag3PO4/OH/TiO2 catalyst with excellent photocatalytic activity under visible light. The test results show that the photocatalytic degradation performance of TiO2 NFs after alkali treatment and Ag3PO4 loading is significantly improved. This is because the alkali treatment and the introduction of Ag3PO4 can provide a large amount of –OH, which can be converted to ˙OH under UV irradiation, followed by an increase in the number of active radicals to enhance the photocatalytic degradation performance. Meanwhile, the introduction of Ag3PO4 can effectively improve the light absorption ability of the photocatalyst. Moreover, the in situ growth of Ag3PO4 on TiO2 NFs can construct a high-quality Ag3PO4/TiO2 heterojunction to promote the charge separation and transport. Therefore, the degradation rate of Ag3PO4/OH/TiO2 can reach 90% after 30 min for degrading 3 mg L−1 RhB under visible light. The Ag3PO4/OH/TiO2 photocatalyst designed in the present work provides a new tool for the degradation of organic dyes. [ABSTRACT FROM AUTHOR]

In this paper, two D–π–A structured self-assembly monolayers (SAMs: FNE29 and DT-1) are self-assembled onto the indium tin oxide (ITO) substrates as hole-transport layers (HTLs) for inverted perovskite solar cells (PSCs). Due to the presence of a terminal –COOH group, the SAMs can be adsorbed onto the surface of the ITO substrate through the covalent self-assembly. The employed FNE29 and DT-1 SAMs differ in the π bridge (linker); the FNE29 SAM has a hexyl-substituent terthiophene while the DT-1 SAM contains dithienopyrrolobenzotriazole as the linkers, respectively. Upon the self-assembly of ITO with the SAMs, the power conversion efficiency (PCE) is enhanced from 9.36% for the control device to 16.75% for the FNE29 modified device and further to 20.65% for the DT-1 modified PSCs. As the D–π–A structured SAMs with a large fused π bridge as a linker is beneficial for hole transfer, the self-assembly of DT-1 achieves a higher PCE with an improved fill factor. Moreover, due to the good hydrophobic characteristics of the SAMs, the inverted PSC devices self-assembled with these two molecules display good stability, maintaining over 80% of the original PCE after storage in air (relative humidity of 20–30%) for ∼1000 h without encapsulation. In addition, the FNE29 and DT-1 based devices also show good photostability after operating for 1000 h. These results indicate that the D–π–A structured SAMs with large conjugated fused π bridges as linkers have obvious advantages as the HTLs for inverted PSCs. [ABSTRACT FROM AUTHOR]

This article introduces functional framework materials, such as metal-organic frameworks (MOFs), covalent-organic frameworks (COFs), hydrogen-bonded organic frameworks (HOFs), and porous organic polymers (POPs). These materials have unique properties that make them useful in various applications, including separation, catalysis, energy storage, sensing, and medicine. The article presents a collection of over 70 papers that contribute to the progress of this field, covering a diverse range of materials, preparation methods, and applications. It emphasizes the interdisciplinary nature of this research field and encourages readers to explore the potential of functional framework materials in sustainable development. [Extracted from the article]

In this paper, a La0.6Sr0.4CoO3/MoS2 composite electrocatalyst was prepared by a sol–gel method and subsequent dry ball milling. It showed high activity and favored the reaction kinetics for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) under alkaline conditions. When applied for overall water splitting, it showed a low full-cell voltage of 1.48 V at 10 mA cm−2 that is comparable to state-of-the-art noble metal catalysts. Using in situ Raman spectroscopy we identified the surface reactive intermediates: cobalt (hydr)oxides with high oxidation states were formed under anodic potentials at the La0.6Sr0.4CoO3/MoS2 interface to facilitate the OER. DFT calculations showed that the two-phase interface facilitated the polarization of the interface charge and modulated the bonding of the reaction intermediates, accelerating the overall water splitting. This work exemplifies the impact of interfacial engineering on the electrocatalytic performance and provides a new route for the development of low-cost and non-noble metal catalysts for water electrolysis. [ABSTRACT FROM AUTHOR]

The advancement in two-dimensional (2D) materials has led to the development of new charging methods in portable and wearable electronic devices. However, their charging methods are still confined to contact/wired mode. Radio Frequency (RF) energy harvesting exhibits potential for extracting electrical power from the environment, benefiting from its limitless ambient availability and extended power transfer capabilities. This paper demonstrates the fabrication of an RF energy harvesting device using liquid phase exfoliated atomically thin earth-abundant pyrite ore (iron sulfide (FeS2)). Owing to pyrite's unique semiconductor properties such as a very small narrow band gap (0.8 eV) and high carrier mobility (360 cm2 V−1 s−1), it is possible to make a Schottky junction with a metal electrode. Hence, we fabricated a Schottky device employing a Ti/2D-FeS2/ITO configuration using drop casting methods. Electrical measurements reveal that the device has a low turn-on voltage of 0.18 V and a low Schottky barrier height of 0.14 eV. To substantiate the role of 2D-FeS2, density functional theory (DFT) studies were performed revealing the impact of the Giant Stark Effect (GSE) in lowering the bandgap of 2D FeS2. This insidious phenomenon of GSE in 2D-FeS2 makes it an ideal material of choice for RF energy harvesting applications. The device we fabricated functions within the commercial frequency modulation broadband range and extends seamlessly into the very high-frequency radio spectrum. It generated a 1.5 V output voltage using commercial FM broadband frequencies, sufficient for charging a 1.5 F supercapacitor. Subsequent experimentation with a handheld walkie-talkie demonstrated that the device could achieve a maximum voltage of 3.5 V within the one-meter range, exhibiting an efficiency of 30%. The implications of this discovery suggest that 2D-FeS2-based wireless energy-powered portable devices hold promise for healthcare/biomedical device applications, energy harvesting in remote areas, and regions affected by floods or natural disasters. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) possess exceptional thermal storage properties, which ultimately reduce energy consumption by converting energy through their inherent phase change process. Biomass materials offer the advantages of wide availability, low cost, and a natural pore structure, making them suitable as carrier materials for biomass composite PCMs. Biomass composite phase change materials can not only address the issue of leakage associated with conventional PCMs during solid–liquid conversion, but also possess environmental protection and biodegradability characteristics. This paper provides a comprehensive introduction to the types and encapsulation methods of PCMs. Based on the current research, this paper introduces the fundamental characteristics of biomass composite PCMs and summarizes the preparation methods. Finally, the future development direction and application of biomass composite PCMs are discussed, offering new insights into PCM research. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Dalton Transactions: An International Journal of Inorganic Chemistry," published by The Royal Society of Chemistry. It includes various articles covering topics such as proton conduction, catalytic dinitrogen reduction, and structural insight into pharmacokinetic parameters. One article titled "Room temperature spin crossover properties in a series of mixed-anion Fe(NH2trz)3(BF4)2−x(SiF6)x/2 complexes" by Xinyu Yang et al. explores the spin crossover properties of these complexes at room temperature. The study investigates how the complexes behave under changes in temperature and pressure, providing insights into their potential applications in molecular electronics and data storage. [Extracted from the article]

Cadmium poisoning is a chronic accumulation process, and long-term drinking of even low cadmium content water will cause kidney damage, so an ultra-low detection limit is particularly important. However, at the present stage, the traditional detection method cannot reach a sufficiently low detection limit, the response time is too long, and the cost of detection is very high, so that real-time measurement cannot be realized. Therefore, the traditional cadmium ion detection method has a slow response and an insufficient detection limit. This paper presents a fiber optic cadmium ion sensor functionalized based on an Fe3O4@SiO2@CS magnetic ion imprinting polymer (M-IIP). The sensor is based on the coupling characteristics of the optical microfiber coupler (OMC) cone region to achieve a highly sensitive response to the change in the cadmium ion concentration. M-IIP materials were prepared by surface imprinting polymerization to achieve low cross-sensitivity and thus improve the detection limit of the sensor. The results show that the developed fiber sensor has high specificity and a rapid response to cadmium ions. The experimental limit of detection (LOD) reached 0.051 nM within 0–1 μM with a response time of less than 50 s. Moreover, the proposed fiber cadmium ion sensor exhibits excellent performance in terms of sensitivity, stability, repeatability and biocompatibility. [ABSTRACT FROM AUTHOR]