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The photocatalytic degradation, as an environmental-friendly technology, has great significance for cost-effective and efficient catalysis processes, wherein piezo-photocatalysis can significantly increase the catalytic degradation rate using both solar and mechanical energy. Here, a ternary heterostructure PVDF/ZnO/Au (PZA) nanobrush photocatalyst with high piezo-photocatalytic efficiency was presented via low-temperature hydrothermal and chemical reduction methods. Under both solar and mechanical energy, the current response and degradation rate of the as-synthesized PZA nanobrush all increase significantly compared with that under solar alone and under mechanical energy alone, and the excellent recyclability is investigated. It is found that the PZA nanobrush with ultrasonic-assisted piezo-photocatalysis completely degrade MO of 20 mg/L in 60 min, which exhibits greater enhancement of photocatalytic activity than with stirring-assisted piezo-photocatalysis due to higher power. The high piezo-photocatalytic activity of PZA nanobrush is attributed to the surface plasmon resonance (SPR) coupling of Au and built-in electric field originating from the ZnO and PVDF, which can increase the absorption of visible light, promote the charge transfer and separation of photogenerated electrons/holes. This work introduces the SPR and bipiezotronic effect to improve plasmonic photocatalysis with PZA heterostructures, which offers a new solution in green technologies to design high-performance catalysts for the environmental remediation.

Rare earth ion-doped inorganic photochromic (PC) materials have recently garnered increasing research interest due to their excellent reversibility, fatigue resistance, and diverse PC performances. Apatite-type materials, in particular, have emerged as a focal point, offering the potential for exchanging multiple cations and anions with stronger tolerance. In comparison to other inorganic PC materials, apatite-type PC materials exhibit more abundant color changes and absorption bands and centers, creating new and substantial opportunities for adjusting and optimizing PC properties, deepening the understanding of PC mechanisms, and enabling construction of novel PC materials and development of multifunctional applications. This review comprehensively summarizes and discusses recent progress in apatite-type PC materials. It covers various aspects, including the PC properties of reported apatite-type PC materials, the pivotal role of traps in PC reactions, the energy transfer mechanism between luminescent centers and color centers, the prediction of PC properties through first-principles calculations, and the systematic regulation of color changes and absorption bands and centers during PC reactions. Benefiting from multiple color variations and extensive absorption band regulation, apatite configuration PC materials exhibit broad prospects and significant potential for various frontier applications, such as optical modulation, photo-switching, anti-counterfeiting, erasable optical information storage, and temperature sensing. Subsequently, this review outlines some challenges and prospects in the research and design of apatite-type PC materials, aiming to guide the exploration of structural design of new inorganic PC materials, further regulating and controlling the PC effect and expanding practical application domains. [ABSTRACT FROM AUTHOR]

Photoreversible, color‐changing films have great potential in various optical applications. In this study, we developed a photochromic film by embedding droplets of metatitanic acid (hydrous TiO2) and glycerol in commercially available poly(dimethylsiloxane) (PDMS) silicone elastomers. Benefiting from the electron–hole pair scavenging abilities of glycerol, the resulting film exhibited rapid photoresponse, high photoreversible stability, excellent antiaging capability, and remarkable stretchability. The degree of color changes upon ultraviolet (UV) irradiation was effectively controlled by adjusting both the concentration of hydrous TiO2 (1–20 wt%) and UV irradiation time (5–30 min), thereby increasing total color‐changing ability (ΔE). High‐resolution patterns could be repetitively printed, erased, and rewritten (≥20 times) with no significant loss of clarity. After a 30‐day exposure to ambient air, there were no significant aging effects in the photochromic ability of the films, thus demonstrating promising potential as rewritable films for information storage. [ABSTRACT FROM AUTHOR]

Wettability modification is an effective way in tailoring hotspots in surface Raman scattering (SERS) nowadays. However, due to the theoretical contradiction between hydrophobic and hydrophilic strategies, opposite views are usually put forward in building SERS structures. To realize the integration of hydrophobicity and hydrophilia in the same substrate, a wettability-switchable SERS architecture composed of heterostructured CuO@ZnO@Ag biomimetic nano Setaria (NS) has been designed and prepared in this paper. Experimentally, the structure shows impressive SERS performance under both hydrophobic and hydrophilic states. The limit of detection approaches even to single-molecule level and the lowest relative standard deviation is only ca 9.8%. Finite-different time-domain simulations and experimental analyses were systemically made to unearth the mechanism deep behind. Besides, owing to fine quantifiability, the CuO@ZnO@Ag NS shows promising potential in the detection of trace pesticide and deoxyribonucleic acid. This work provides a new idea for integrating the strategies of ‘concentration’ and ‘decentralization’, endowing SERS structure with wider application, and is also meaningful for other surface sciences.

Highly efficient plasmon-driven catalysis and excellent surface-enhanced Raman spectroscopy (SERS) performance are proportional to the square of the local electromagnetic field (hot spot). However, a proven way to realize the enhancement in intensity and density of “hot spot” still needs to be investigated. Here, we report on multilayered Ag nanoparticle (Ag NP)/graphene coupled to an underlying Cu film system (MAgNP-CuF) which can be used as an effective SERS substrates realizing ultra-sensitive detection for toxic molecules and in situ monitoring the plasmon-driven reaction for p-nitrothiophenol (PNTP) to p,p′-dimercaptobenzene (DMAB) conversion. The mechanism of ultra-sensitive SERS response and catalytic reaction is investigated via Ag NP/graphene layer-dependent experiments combined with theoretical simulations. The research found that the intensity and density of “hot spot” can be effectively manipulated by the number of plasmonic layers, and the bottom Cu film could also reflect the scattered and excitation beam and would further enhance the Raman signals. Moreover, the MAgNP-CuF exhibits outstanding performance in stability and reproducibility. We believe that this concept of multilayered plasmonic structures would be widely used not only in the field of SERS but also in the wider research in photocatalysis.

NIR luminescent materials are widely available for biological applications, and the NIR emitting of Ho3+ ions has received widespread attention in the second biological window. In this work, Ca14Zn6Ga10O35 : Mn4+,Ho3+ luminescent materials were synthesized using a high temperature solid state method. Optical properties and energy transfer mechanisms have studied in detail. Upon UV‐vis light excitation, the Mn single doped Ca14Zn6Ga10O35 phosphors exhibit deep red and NIR emission centered at 712 and 1151 nm assigned to Mn4+ and Mn5+, respectively. Another stronger NIR emitting peaked at 1195 nm occurs when the Ho3+ ion is co‐doped into Ca14Zn6Ga10O35 : Mn4+. The energy transfer from Mn4+ to Ho3+ ion is performed through a resonant type by a dipole‐dipole interaction mechanism. In addition, the thermal stability of Ca14Zn6Ga10O35 : Mn4+,Ho3+ phosphor has been investigated, and the NIR emission of Ho3+ ion maintains more than half the strength at 423 K. The findings indicate that the as‐prepared Ca14Zn6Ga10O35 : Mn4+,Ho3+ luminescent materials hold promise for potential applications in the second biological window. [ABSTRACT FROM AUTHOR]

Cavity array, with excellent optical capture capability, has received increasing attention for the surface-enhanced Raman spectroscopy (SERS)-active substrates. Here, we proposed molybdenum disulfide (MoS2) nanocavities growing on pyramid Si (PSi) composed of in situ reduced Au nanoparticles (AuNPs), which can form the multiscale cavities (MSCs), and is facile for the couple of the plasmon. We demonstrated that the PSi/MoS2/Au MSCs can serve as highly sensitive, uniform, and stable SERS substrates for rhodamine 6G (R6G), crystal violet, and adenosine triphosphate detection, benefiting from the synergistic effect of the enhanced light trapping and the effective plasmonic couple. The couple of the plasmon in the MSCs is evidently proved by finite-difference time domain simulation, showing the strong electromagnetic field is located around the cavity wall. Moreover, the excellent hydrophobicity of the PSi/MoS2/AuNPs substrate endows it with the ability for the directional monitoring of organic pollutant in a mixture of oil and water. Finally, we demonstrated the MSCs with outstanding photocatalytic performance could achieve the renewable utilization by self-cleaning, which was attributed to the fast electron transfer and effective light absorption. The proposed PSi/MoS2/AuNPs MSC represents a robust mean using the plasmonic metal/semiconductor heterostructure for high-performance SERS sensors and photodegradation.

Astronomic positioning and orientation can be used to obtain the astronomic longitude and latitude of a station and the astronomic azimuth of a ground target by observing stars. The results of the positioning and orientation depend not only on the instrument, environment, and observed star, but also on the solution method. Due to atmospheric refraction and instrumentation, there is a systematic error in the zenith distance of observed starlight during astronomic measurements using theodolites. The existing methods either do not consider the systematic error of the zenith distance, or do not fully utilize all directional information of the star. Therefore, existing methods cannot simultaneously achieve high-accuracy astronomic positioning and orientation, particularly in the case of poor stellar distribution. To address this problem, an astronomic positioning and orientation method that considers the zenith distance system error is proposed. The experimental results showed that the proposed method had a higher positioning accuracy than the traditional astronomic positioning method. In addition, the new method showed significant advantages in instances of inhomogeneous distribution such as cloudy or daytime observation. [ABSTRACT FROM AUTHOR]