Considering the close association between the abnormal expression of multiple microRNAs (miRNAs) and various diseases, multi-channel detection of miRNAs holds significant importance for disease diagnosis. However, traditional miRNA detection methods fall short of simultaneously achieving the required specificity, sensitivity, and multi-channel capability. To address this challenge, we developed a chain-based precision amplification photoelectrochemical biosensor for the simultaneous detection of multiple miRNAs, based on dCas13a system and iridium complex. The precise recognition of miRNA is achieved by the dCas13a-crRNA complex and then converted into a significant photocurrent response from iridium nanocomposite attached to a long double-stranded nucleic acid chain, thereby enabling signal amplification, namely chain-based precision amplification. The dCas13a-crRNA complex is modified onto a multi-channel electrode to simultaneously recognize and bind multiple target miRNAs. The iridium complex is modified on the surface of energy-levelmatched quantum dots to suppress carrier recombination, and Au nanoparticles are further modified on the surface of the quantum dots, thereby constructing a nanocomposite for efficient photoelectric conversion. A double-stranded sequence is constructed at the 3 ' end of the miRNA to increase the attachment sites for the nanocomposite. The biosensor demonstrates exceptional specificity and sensitivity, capable of distinguishing single-base differences with a detection limit as low as the aM level, benefiting from the chain-based precision amplification. Furthermore, clinical sample testing underscores the practical applicability of the biosensor in clinical diagnostics. This multi-channel chain-based precision amplification biosensor offers a highly valuable and innovative approach for the simultaneous detection of multiple miRNAs, with considerable potential for clinical diagnostic applications.

Non-radiative recombination is the key bottleneck to overcome the charge separation problem. Here, we use poly(heptazine imide) (PHI) as a model photocatalyst to investigate the effect of internal electric field (IEF) on non-radiative recombination. Introducing electron-deficient boron atoms into the PHI structure leads to an uneven distribution of in-plane charges, spontaneously polarizing the formation of an IEF. This enhanced IEF can exert a force on the carrier in the opposite direction of the Coulomb force, thus effectively weakening the carrier trapping by the charged defect, thereby suppressing the non-radiative recombination. This is the first systematic research of suppressing non-radiative recombination by IEF in photocatalysis, which provides guiding strategies for addressing the bottleneck of charge separation in photocatalysis.

The polarization of electromagnetic waves is a fundamental property that influences their propagation direction and state, represents a critical physical parameter in modern applications such as signal transmission, target recognition, and precision measurement. Conventional polarization control devices based on metamaterials are often sensitive to structural perturbations, presenting challenges for practical applications. In contrast, topologically protected photonic devices have demonstrated that photon topological edge states can effectively overcome scattering losses caused by disorder and structural perturbations. The prospect of utilizing the robustness of topological edge states to design reliable electromagnetic wave polarization devices has thus become an increasingly significant research focus. We design and construct a curved photonic dimer chain composed of subwavelength resonators and experimentally verify that its topological edge states are immune to internal disorder perturbations, enabling efficient long-range electromagnetic wave polarization conversion. Based on this study, future investigations could explore more complex topological architectures, such as quasiperiodic or trimer chains, to achieve enhanced multifunctional polarization control. Furthermore, we could consider integrating exceptional points in non-Hermitian systems to design chiral polarization devices.

Vibrational dynamics and energy transfer were identified by femtosecond time- and frequency-resolved coherent anti-Stokes Raman scattering spectroscopy. Nitromethane (NM) was selectively and collectively excited in an orderly manner. The beating modes involving vibrations were described and the dephasing time of theses vibrational modes was monitored. The results indicated that intramolecular vibrational energy transfer was governed by vibrational couplings. When the NM/methanol mixed solutions were collectively excited, no evidence for a beat or intermolecular energy transfer was found because hydrogen bonds acted as a molecular damper yielding a faster decay of molecular dynamics.

The construction of heterojunctions is challenging, requiring atomic-level contact and interface matching. Here, we have achieved atomic-level interfacial matching by constructing poly(heptazine imide)/poly(triazine imide) crystalline carbon nitride heterojunctions in an in-situ one-step method. The content of poly(triazine imide) in heterojunctions is positively related to the proportion of lithium chloride in potassium chloride and lithium chloride mixed-salts. The optimized heterojunction achieves an apparent quantum efficiency of 48.34 % for photocatalytic hydrogen production at 420 nm, which is at a good level in polymeric carbon nitride photocatalysts. The proposed ion-thermal assisted heterojunction construction strategy contributes to the development of polymeric carbon nitride photocatalysts with high crystallization and high charge separation efficiency.

Vibrational energy transfer was a key property of chemical reactions that remains deeply understood. In this work, the detail information of vibrational energy transfer in aniline, N,N-dimethylaniline (DMA) and N,N-diethylaniline (DEA) were studied by femtosecond time-resolved coherent anti-Stokes Raman scattering (CARS) spectroscopy, respectively. Low frequency modes of aniline, DMA and DEA were collectively excited, the beats arising from vibrational couplings among these modes were described. With analysis of vibrational coupling, energy transfer flow from one mode to another was visualized. An investigation into the molecular structure and vibrational couplings can be found that vibrational energy transfer is related to vibrational mode symmetry. In addition, substituent groups play an important role in vibrational coupling and energy transfer of aniline, DMA and DEA. A decrease of the number of substituent vibrational modes involved in coupling and energy transfer efficiency with the increase of the amount of relative molecular mass ratio was found out.

Spin- and angle-resolved photoemission spectroscopy ("spin-ARPES") is a powerful technique for probing the spin degree-of-freedom in materials with nontrivial topology, magnetism, and strong correlations. Spin-ARPES faces severe experimental challenges compared to conventional ARPES attributed to the dramatically lower efficiency of its detection mechanism, making it crucial for instrumentation developments that improve the overall performance of the technique. In this paper, we demonstrate the functionality of our spin-ARPES setup based on time-of-flight spectroscopy and introduce our recent development of an electrostatic deflector mode to map out spin-resolved band structures without sample rotation. We demonstrate the functionality by presenting the spin-resolved spectra of the topological insulator Bi2Te3 and describe in detail the spectrum calibrations based on numerical simulations. By implementing the deflector mode, we minimize the need for sample rotation during measurements, hence improving the overall efficiency of experiments on small or inhomogeneous samples.

Two-dimensional (2D) metal-organic frameworks (MOFs) have attracted considerable attention owing to their fascinating properties, including ordered crystalline structures, large surface areas, and related unique 2D properties. Moreover, 2D MOFs have been widely used in energy, catalysis, and optoelectronic applications. However, researchers have performed fewer investigations on photonic applications. To remedy this gap in knowledge, recent progress in the development of 2D MOFs for photonic applications was investigated. First, the background and motivation of this review are introduced. Then, the synthesis method and properties are presented, followed by an introduction to their photonic device applications. Finally, future research prospects and challenges in 2D MOFs for photonic applications are proposed.

Many biological surfaces with hierarchical structures exhibit super wetting properties, but a multiscale hierarchical metal surface with superhydrophilic performance is difficult to be fabricated using a simple method. In this work, we report a large area micro/nanotextured superhydrophilic silicon surface fabricated by a laser direct writing technique. The combination of a microscale column structure and randomization-distributed nano-bumps decorated on the column enhances the superhydrophilic properties, with the contact angle reduced substantially from about 46° to 0°, where the droplets are able to spread rapidly within 591 ms. The water wetting orientation can be regulated by controlling the shape of microcolumns on the surface. Moreover, our results show that the fabricated surface with the hierarchical structure has better droplet shape control performance and higher fog collection efficiency compared to a smooth surface. These surfaces have potential applications in heat exchangers, biosensors, cell adhesives, and self-cleaning solar cells.

In the present work, the structure, magnetic properties, and cryogenic magnetocaloric effect of weberite-type oxides Gd3MO7 (M = Nb, Sb, and Ta) are reported through powder X-ray diffraction, bulk susceptibility, and heat capacity measurements, as well as scaling law analysis and a mean-field approach. A remarkably large isothermal magnetic entropy change of 354.0 mJ K-1 cm(-3) is observed for Gd3SbO7 under an external field of 9 T at 2.0 K. The relative cooling power is estimated to be 618.9 J kg(-1) (4.8 J cm(-3)) for an applied field of 8.9 T, with the largest adiabatic temperature change being 22.4 K at 6.3 K. The magnetocaloric performance of these oxides is quite impressive when compared with the benchmark magnetic refrigerant, gadolinium gallium garnet (Gd3Ga5O12, GGG). Therefore, Gd3MO7 (M = Nb, Sb, and Ta) are promising alternatives for cryogenic cooling techniques, especially for the magnetic liquefaction of helium.

Two-dimensional (2D) materials have garnered considerable attention due to their advantageous properties, including tunable bandgap, prominent carrier mobility, tunable response and absorption spectral band, and so forth. The above-mentioned properties ensure that 2D materials hold great promise for various high-performance infrared (IR) applications, such as night vision, remote sensing, surveillance, target acquisition, optical communication, etc. Thus, it is of great significance to acquire better insight into IR applications based on 2D materials. In this review, we summarize the recent progress of 2D materials in IR light emission device applications. First, we introduce the background and motivation of the review, then the 2D materials suitable for IR light emission are presented, followed by a comprehensive review of 2D-material-based spontaneous emission and laser applications. Finally, further development directions and challenges are summarized. We believe that milestone investigations of 2D-material-based IR light emission applications will emerge soon, which are beneficial for 2D-material-based nano-device commercialization.

Magnetic topological insulator MnBi 2 Te 4 is an intrinsic van der Waals layer structure compound. The interplay between magnetism and topology makes MnBi 2 Te 4 a good platform to investigate controllable topological phase transition and emerging physical states such as quantum anomalous Hall state and Weyl semimetal phase. Crystal characterization showed a rhombohedral unit cell composing of Te-Bi-Te-Mn-Te-Bi-Te septuple layer (SL) coupled antiferromagnetically. Systematically investigation of surface states with angle-resolved photoemission spectroscopy and of bulk states with transport measurement showed detailed electronic structure of MnBi 2 Te 4 crystal. Rich topological phases were observed in MnBi 2 Te 4 . Temperature, doping and external magnetic field could affect the different topological phases and induce phase transitions in certain conditions. Quantum anomalous Hall effect (QAHE) was realized at as high as 6.5 K in 5-SLs MnBi 2 Te 4 flake. Furthermore, the negative to positive magnetoresistance transition and the thickness dependent QAHE Chern number of MnBi 2 Te 4 provide strong evidences for the Weyl semimetal states in this material. Based on experiments done from 2019 to 2022, our review should shed light on future research opportunities on MnBi 2 Te 4 compound.

Energy transfer is an important phenomenon of physicochemical systems vibrationally coupled to an environmental bath. For a condensed system, energy exchange from one mode to another is the first step of chemical reactions. In this work, we use femtosecond time- and frequency-resolved coherent anti-Stokes Raman scattering (CARS) spectroscopy technique to track molecular dynamics and energy transfer in pure aniline and its mixed solutions. In pure aniline, oscillatory structures in time- and frequency-resolved CARS spectra indicate that vibrational modes participate in the vibrational coupling, and the vibrational coupling process is necessary for energy transfer. In the Rh101(+)/aniline mixed solution, vibrational dynamics and energy transfer processes are not detected due to strong hydrogen interactions. By comparing the experimental results for the pure aniline and the Rh101(+)/anilinemixed solution, we find that energy transfer in the pure aniline depends mainly on the vibrational coupling; in the Rh101(+)/aniline mixed solution, hydrogen bonds act as the molecular damper, which leads to a faster decay in the vibrational dynamics.

Bismuth-based binary compounds, including Bi 2 Se 3 and Bi 2 Te 3 , have attracted increasing attention as well-known topological insulators. On the other hand, bismuth-based ternary compounds exhibit diverse properties, such as, ultrahigh carrier mobility, and strong Rashba spin splitting. Moreover, they boast of superior photocatalytic properties, implying great potential to be used in a wide range of applications. The unique structure and properties of two-dimensional (2D) materials, especially the extraordinary electronic and optical properties of 2D Bi 2 O 2 Se, have given rise to significant research interests for the exploration of 2D bismuth-based ternary compounds. In this review, we will comprehensively discuss the properties of three important families of bismuth-based ternary compounds, including Bi 2 O 2 X (X = S, Se, Te), BiTeX (X = Cl, Br, I), and BiOX (X = Cl, Br, I). In particular, we have placed emphasis on the latest progress in their 2D forms, including their novel properties and applications. This review would aid in understanding the superior performance of bismuth-based ternary compounds and offer a perspective for future research on these emerging 2D materials.

The electric field control of Raman scattering for small molecules can be realized in direct semiconducting antimonene-based field effect transistor.

As a rare typical p-channel layered oxide semiconductor, two-dimensional tin monoxide has attracted great attention due to its wide promising applications in nano-electronics. Using the first-principles calculation, we studied the effects of multi-hydrogen-tin/oxygen vacancy complex impurities on the electronic properties of the p-type monolayer SnO. The calculation results indicated that O vacancy (VO) is a donor and Sn vacancy (VSn) acts as a double acceptor. VSn should be the source of p-type in undoped SnO in an O-rich environment. When hydrogen is introduced, the more stable nH-VSn (n = 1, 2, and 3) complex defects can be formed. These complex impurities can affect the p-type SnO monolayer in the following three main ways: (i) the p-type H-VSn compensates the deeper acceptor level of VSn and enhances the majority carrier mobility. (ii) The more stable 2H-VSn neutralizes the p-type dopant nature of VSn and H-VSn. (iii) The 3H-VSn converts the defect to be an n-type dopant. Our results indicated that limitation of hydrogen is necessary for the preparation of high-quality p-type two-dimensional SnO, as a small amount of hydrogen produces positive effect on p-type SnO; however, the higher concentration of hydrogen is destructive to the p-type character of monolayer SnO.

The photoresponse of Bi2O2Se/SrTiO3 photodetectors is governed congruously by photon and thermal-induced effects, which is critically impacted by interfacial interaction.

Polycrystalline film photodetectors often suffer from several drawbacks, such as uncontrollable defect species, grain boundary scattering, and surface oxygen trapping/detrapping, hindering their practical applications in high-performance UV photodetection. In this work, we induce an acceptor-type zinc vacancy (V-Zn ) defect in zero-dimensional ZnO nanocrystals by a dual thermal annealing process, which has been closely examined by a defect-sensitive electron paramagnetic resonance technique. The optimization of annealing parameters can well tune the V-Zn concentration and induce a considerable self-powered behavior, which is believed to result from ionized acceptor enhanced charge separation. On the other aspect, the capping of metallic Zn can lead to the formation of abundant interface conducting channels for the highly efficient charge transport and extraction. The optimized responsivity is enhanced from 5.3 x 10(-3) to 15.3 A W-1, and the average rise and decay times remain at 36.6 and 101.8 ms, respectively. Conductive atomic force microscopy confirms a uniform photocurrent distribution in the annealed polycrystalline films, suggesting the significance of synergies of lattice defects and grain boundary conductive channels. This study unambiguously demonstrates a new route to engineer the photodetection in nanocrystalline oxides, providing a promising prospect for future low-cost, low-power-consumption micro-/nano-optoelectronic devices.

Recently, Bi2O2Se was revealed as a promising two-dimensional (2D) semiconductor for next generation electronics, due to its moderate bandgap size, high electron mobility and pronounced ambient stability. Meanwhile, it has been predicted that high-quality Bi2O2Se-related heterostructures may possess exotic physical phenomena, such as piezoelectricity and topological superconductivity. Herein, we report the first successful heteroepitaxial growth of Bi2O2Se films on SrTiO3 substrates via pulsed laser deposition (PLD) method. Films obtained under optimal conditions show an epitaxial growth with the c axis perpendicular to the film surface and the a and b axes parallel to the substrate. The growth mode transition to three-dimensional (3D) island from quasi-2D layer of the heteroepitaxial Bi2O2Se films on SrTiO3 (001) substrates is observed as prolonging deposition time of films. The maximum value of electron mobility reaches 160 cm2 V-1 s-1 at room temperature in a 70 nm thick film. The thickness dependent mobility provides evidence that interface-scattering is likely to be the limiting factor for the relatively low electron mobility at low temperature, implying that the interface engineering as an effective method to tune the low temperature electron mobility. Our work suggests the epitaxial Bi2O2Se films grown by PLD are promising for both fundamental study and practical applications.

2D van der Waals (vdW) magnets, which present intrinsic ferromagnetic/antiferromagnetic ground states at finite temperatures down to atomic-layer thicknesses, open a new horizon in materials science and enable the potential development of new spin-related applications. The layered structure of vdW magnets facilitates their atomic-layer cleavability and magnetic anisotropy, which counteracts spin fluctuations, thereby providing an ideal platform for theoretically and experimentally exploring magnetic phase transitions in the 2D limit. With reduced dimensions, the susceptibility of 2D magnets to a large variety of external stimuli also makes them more promising than their bulk counterpart in various device applications. Here, the current status of characterization and tuning of the magnetic properties of 2D vdW magnets, particularly the atomic-layer thickness, is presented. Various state-of-the-art optical and electrical techniques have been applied to reveal the magnetic states of 2D vdW magnets. Other emerging 2D vdW magnets and future perspectives on the stacking strategy are also given; it is believed that they will excite more intensive research and provide unprecedented opportunities in the field of spintronics.