Structural chirality has been imposed onto nano-alloys to introduce diverse new properties. Chiral nanoparticles (CNPs) with the atomic scale chirality are composed of metastable chiral lattices having low thermal stability, so multielementary (>2 elements) CNPs are very challenging to produce using traditional high-energy fabrication methods. Herein, layer-by-layer glancing angle deposition (LbL-GLAD) at a low substrate temperature of ≈−40 °C, consisting of GLAD of the host CNPs and the subsequent GLAD of guests, is devised to extend the alloy compositional space to the ternary (e.g., Ag:Al:Cu and Ag:Al:Au) and quaternary (e.g., Ag:Al:Cu:Au and Al:In:Sn:Ti). The low-temperature GLAD-induced alloying facilitates the formation of the metastable multi-layer chiral twisting of achiral facets, chiral defects due to the diffusion of the guests, and chiral electronic bands, leading to a significant amplification of chiroplasmonic optical activities in 20–30 folds. The LbL-GLAD can be generally adapted to fabricate multielementary alloy CNPs composed of a wide range of elements, with a prospective application of asymmetric catalysts to synthesize an enantiomer with designable chirality, one of the most important topics in modern chemistry and biochemistry to solve the problems of health and environmental pollution.

PbSe has attracted wide attention owing to its fascinating physical and chemical properties. It has important technical significance for infrared detectors. However, due to the inherent bandgap, low carrier mobility, and dielectric constant of PbSe, it is a significant challenge to realize fast response and mid-infrared (MID) photodetection. Chemical doping is an efficient method to regulate the band structure and carrier mobility of materials. Nevertheless, the doped film detector cannot satisfy the demands of high-performance photodetectors. In this paper, different composition ratios powders are synthesized by a solid-state method. The PbSe0.5Te0.5 alloy film displays narrower bandgap, higher carrier mobility, excellent photo-response, and broadband detection capacity. By utilizing the above superiority of PbSe0.5Te0.5 and fast charge transfer in MoSe2, a PbSe0.5Te0.5/MoSe2 p-n heterostructure device is successfully fabricated that has significant rectifying effect (103) and extremely low dark current density (720 µA cm−2). The photodetector has a maximum responsivity (R) and specific detectivity (D*) of 17.5 A W−1 and 3.08 × 1013 Jones at 780 nm. In addition, the detector displays superior photodetection performance with broadband photodetection (405–5000 nm), high switch ratios (Ion/Ioff = 105), and fast response speed. The above outstanding properties indicate that the PbSe0.5Te0.5/MoSe2 heterostructure provides a promising and efficient strategy for achieving a miniaturized, broadband, and high-performance photodetector.

Photovoltaic technology is a prominent source of renewable energy, but maintenance costs and efficiency attenuation of large photovoltaic devices are significant issues due to their vast energy conversion area. To reduce costs and facilitate maintenance, superhydrophobic surfaces with self-cleaning properties have been developed for photovoltaic glass. In this study, transparent ZnO nanoarrays (NAs) are synthesized on photovoltaic glass, with Eu3+ doping enhancing the ultraviolet radiation resistance of photovoltaic devices and slightly increasing visible transmittance. A TiO2 passivation layer is introduced on the ZnO NAs surface to enhance acid resistance and mitigate corrosion caused by acidic rainwater. Fluoroalkylsilane (POTS) modification achieves superhydrophobicity with a water contact angle of 160.25°, as demonstrated by droplet rolling experiments. Micro-interaction of superhydrophobic properties is further investigated by force curve measurement using atomic force microscope, showing almost no nanometer water moisture on the superhydrophobic surface, but conspicuous water moisture on the control glass surface. Finally, simulated models and practical silicon crystal solar cells fabricated using the self-cleaning glass show excellent acid rain resistance, self-cleaning, and long service life properties, with no power conversion efficiency degeneration during a 40-day outdoor application test.

ATP plays a prominent role in shaping the evolution of immune cell responses to injury, infection, and cancer. However, real-time monitoring of ATP levels in vivo remains a challenge, due to the lack of reliable tools that work reversibly in deep tissues. Herein, based on the Förster resonance energy transfer (FRET) strategy, a reversible ratiometric second near-infrared window (NIR-II) molecular fluorescent probe (CX-RATP) is designed and synthesized. CX-RATP exhibits a significant fluorescence ratio change with the existence of 0–10 mM ATP in vitro, which is within the range of physiological and pathological ATP concentrations. Meanwhile, the recognition process can be reversed by apyrase. It can capture the increase and decrease in ATP levels in real time before and after the treatment of acute inflammation. Besides, CX-RATP is also successfully applied to the hepatocellular carcinoma (HCC) model and achieves in situ imaging of tumor lesions. These results all provide solid proof that CX-RATP is a powerful tool for in vivo real-time ATP detection.

Surface enhanced infrared absorption (SEIRA) spectroscopy is a powerful tool in which plasmonically enhanced electromagnetic fields provide high-sensitivity molecular detection. Most SEIRA platforms operate at a single resonant frequency, which must be tuned to match that of the target molecule, and commonly rely on time-consuming lithographic techniques. This study presents a high-throughput and cost-effective plasmonic metasurface for broadband, tunable, and strong infrared signal enhancement. The platform is built upon the principle of dispersion-engineered plasmonic Fabry–Pérot (FP) nanocavity arrays. It offers 1) tight squeezing of infrared (IR) photons into deep sub-wavelength nano-volumes and 2) spectrally tunable near-field enhancements of up to ≈106, two to three orders of magnitude higher than most optical metasurface systems. By coupling multilayer nano-thin film deposition and nanoskiving fabrication techniques, the dispersive FP metasurfaces can be rapidly and reproducibly constructed in a scalable and lithography-free manner. Using IR spectroscopy, the selective and sensitive label-free detection of a molecular monolayer is achieved at a range of frequencies. An enhancement factor of nearly 105 is measured at the carbonyl (C = O) vibrational marker band of the molecule. The confluence of high field enhancement, broadband plasmonic response, and facile fabrication makes this metasurface a promising platform for SEIRA spectroscopy.

Two-dimensional (2D) hexagonal boron nitride (hBN) is one of the most promising candidates to host solid-state single photon emitters (SPEs) for various quantum technologies. However, the 2D nature with an atomic-scale thickness leads to inevitable challenges in spectral variability caused by substrate disturbance, lattice strain heterogeneity, and defect variation. Here, three-dimensional (3D) nanoarchitectured hBN is reported with integrated SPEs from native defects generated during high-temperature chemical vapor deposition (CVD). The 3D hBN has a quasi-periodic gyroid minimal surface structure and is composed of a continuous 2D hBN sheet with built-in convex and concave curvatures that promote the formation of optically active and thermally robust native defects. The free-standing feature of the gyroid hBN with a nearly zero mean curvature can effectively eliminate the substrate disturbance and minimize lattice strain heterogeneity. As a result, naturally occurring defects with a narrow SPE spectral distribution can be created and activated as color centers in the 3D hBN, and the density of the SPEs can be tailored by CVD temperature.

To date, researchers face a huge challenge in synthesizing blue perovskite quantum dots (PQDs) with short-chain ligands since the short-chain ligands increase the polarity and decrease solubility in common non-polar solvents during syntheses. The use of polar solvents to replace non-polar ones may solve the solution problem, but polar solvents will decompose PQDs. So, the key to successful synthesis of PQDs with short-chain ligands is to find polar solvents that can dissolve short-chain ligands well and do not destroy perovskites concurrently. Herein, a room-temperature synthesis method for deep-blue CsPbBr3 PQDs with short-chain ligands is proposed by using eco-friendly ethyl acetate polar solvent. CsPbBr3 PQDs with an average size of 3.87 nm and a peak wavelength of 454 nm are synthesized with a photoluminescence quantum yield of 48.4%. With an interlayer modification to the hole transport layer, the deep-blue perovskite light-emitting diodes realize a maximum external quantum efficiency of 4.39% and half-lifetime of 4.5 min at a maximum brightness of 72 cd m−2. This work offers a novel eco-friendly avenue for the preparation of effective PQDs including blue ones, which will accelerate commercialization of PQDs in lighting and HD full-color displays as well as reduce discharge of solvent pollutants and protect the global environment.

Graphene lithography is crucial for various graphene-based devices, showing considerable potential in the fields of energy, environment, electronics, and optics. Recent reports show that graphene can be facilely fabricated and simultaneously patterned without masks via laser direct writing on a graphene oxide (GO) film. Thus, this laser-reduced graphene oxide (LRGO) is successfully applied for graphene holograms with advantages of being ultra-thin, wide-angle viewing, and full-color display. However, owing to the absence of an effective approach for oxidizing LRGO, the graphene holograms are only written once, not rewritable. This study demonstrates that LRGO can be oxidized with oxygen plasma treatment, enabling the development of rewritable graphene holograms through laser reduction and plasma oxidization. Laser irradiation can directly reduce GO and simultaneously achieve patterning. The oxygen plasma treatment gradually oxidizes and removes the as-prepared LRGO. Using a computer-calculated hologram pattern, the laser system can manufacture a thin graphene hologram in seconds. The fabricated graphene hologram image can be erased with oxygen plasma treatment, preparing the GO film for new hologram writing. This facile, low-cost, erasable graphene lithography process paves the way for various graphene applications in metasurfaces, device fabrication, imaging, data storage, and displays.

Room temperature phosphorescence (RTP) materials have wide applications, and guest/host doping is an important method to achieve RTP. Although weak host–guest interactions (such as hydrogen bonding and π–π stacking) are considered to play a key role in inducing RTP in most doped systems (DSs), stronger and facile coordination bonds can achieve RTP more effectively and are believed to do so in DSs in related research. However, there is a lack of solid experimental evidence. Herein a new stable ligand-modified lead halide (PCB) is synthesized and used as matrix to prepare RTP NA/PCB DSs with naphthalene derivatives (NA) as guests. Remarkably, a coordination bond between host and guest is experimentally demonstrated and revealed to play a decisive role in the generation of efficient RTP. On this basis, a coordination-driven doping strategy is proposed to achieve efficient, multicolored, and long-lived RTP of the DSs. In addition, NA/PCB shows excellent RTP stability and can be used in advanced security encryption, white light emitting diodes, and phosphorescent temperature sensors. This work not only proves the important role of coordination bonds in the RTP DSs, but also shows the potential of the ligand-modified lead halide matrix as the host material of RTP.

Tailoring the solar spectrum is critical for energy devices including solar cells and colorful radiative coolers, requiring additional photonic structures with manipulation capabilities adaptable to different application circumstances. However, existing photonic structures cannot effectively balance the trade-offs between these energy devices' primary functionality, coloration, and visible transparency. Here, a series of planar coupled nanocavities (PCNs) are designed and fabricated, which can manipulate the solar spectrum of energy devices more versatilely than conventional planar multilayers. By judiciously designing and tailoring the coupling effect in the PCNs, the transmissive colors of the PCNs can occupy 99.9% of the sRGB area provided the benchmark for window applications is achieved (average visible transmittance, AVT > 25%), while 25.4% of the sRGB area can be covered by the reflective colors of sub-ambient radiative coolers with PCNs. Moreover, when serving as the semitransparent electrodes of colorful organic solar cells (OSCs), the PCNs can provide a significantly larger color gamut than commonly used multilayered electrodes under different performance benchmarks. Remarkably, the PCNs can even locally break the trade-offs between the power conversion efficiency (PCE) and AVT and electrode conductivity of the OSCs. The proposed PCNs provide a promising route for delicately tailoring the solar spectrum with simple multilayered structures.

The size- and shape-dependent localized surface plasmon properties of metallic nanoparticles (NPs) enable nanoscale-enhanced near-field applications in a wide range of fields, including spectroscopy, nonlinear optics, and sensing. Orderly assembled NPs can construct plasmonic metamaterials for light manipulation at a subwavelength scale, exhibiting new collective properties in resonant modes regulated by plasmon coupling between their fundamental components. Despite the recognition of its significant advantages in photonics integration, plasmonic-based tailored optical responses for practical applications have remained elusive due to limitations in scaling up processes, as neither etching nor assembly can design and fabricate embedded plasmonic devices into functional devices/structures. Here, the assembly of plasmonic NPs is demonstrated by ultrafast laser-induced writing-on-demand inside solids, tailoring their distribution and sizes. By controlling the laser scanning speed, the in situ redistribution of NPs is observed. Plasmon mediated local energy deposition is considered as the main mechanism driving nano-patterning at a subwavelength range. A direct nano-printing is realized by utilizing the resonant optical response of laser-modified NP structures/patterns. This work paves the way for directly induced NP composite structures inside transparent materials at a well-defined and controlled depth for plasmonic applications.

Multicolor photoluminescent Bi0.4Ln0.1Na0.5Ta2O72− nanosheets (Ln = Eu, Tb, Dy, Sm, La) are prepared by delaminating an Aurivillius-phase layered perovskite, Bi2.4Ln0.1Na0.5Ta2O9. Both Bi3+ and Ln3+ (except La3+) successfully function as luminescent centers under UV-light illumination (λex. = 240–340 nm), which result in a photoluminescence color that can be tuned by changing the lanthanide doping. The emission spectra are influenced by pH because the energy distribution to Ln3+ or to Bi3+ is different in acidic or in basic solutions. Freestanding Bi0.4Ln0.1Na0.5Ta2O72− nanosheet membranes are prepared by vacuum filtration, and the relationship between the photoluminescence and structural properties of the nanosheet membranes is investigated. The results indicate that differences in the electron orbitals involved in the photoluminescence of Bi3+ (6s2–6s6p) and Ln3+ (4fn–4fn) influence the responsiveness to changes in the environment surrounding those luminescent centers.

Organic hybrid halide perovskite, which has excellent characteristics of low cost, nontoxicity, and high recognition, has attracted extensive attention in optical anticounterfeiting applications. In this paper, (TEA)2ZrCl6 (TEA = tetraethylammonium) single crystals (SCs) are synthesized by an easy-to-operate hydrothermal method, which exhibits excitation wavelength-dependent emission at 254 and 365 nm, respectively. Moreover, the photoluminescence quantum yield of (TEA)2ZrCl6 SCs achieves 84.7%, with the introduction of Sb3+ ions. (TEA)2ZrCl6 and doped (TEA)2ZrCl6 patterns can be recognized with excitation by different wavelengths. In addition, as-prepared (TEA)2ZrCl6 crystals show interesting radioluminescence for another anticounterfeiting model with the light yield of 17 709 photons per MeV. The experimental results indicate the novel (TEA)2ZrCl6 SCs have a huge potential for X-ray imaging and anticounterfeiting.

The development of rapid, sensitive, and intuitive intelligent fluorescent materials (IFMs) for monitoring beverage safety is important for human health. In this study, an emerging IFM, a dual-emitting Eu3+-functionalized hydrogen-bonded organic framework (Eu@HOF, Eu@1), is fabricated through coordination post-synthetic modification. The ligand-to-metal charge transfer-induced energy transfer (LMCT-ET) from 1 to Eu3+ provides Eu@1 with palpable red fluorescence. Eu@1 as a sensor can specifically discriminate coumarin (Cou), a common spice used in beverages but a suspected carcinogen, with high sensitivity, high efficiency, and excellent anti-interference. Eu@1 can also quantitatively distinguish 7-hydroxycoumarin (umbelliferone, Ulf), a metabolite of Cou, in chromatic and ratiometric modes. In realistic milk and soy milk samples, the detection limits (DL) of Eu@1 for Cou are 0.0979 and 0.0511 mg L−1, respectively, whereas that of Ulf in practical serum samples is 0.0099 mg L−1. Furthermore, based on the polyethylene-vinyl acetate (PEVA) films, three digital anti-counterfeiting platforms with multiple encryption information are constructed, assisted by a support vector machine. This work proposes a facile pathway for preparing Eu@HOF fluorescent sensors to determine beverage safety and opens the possibility of designing an efficient and precise multifunctional digital anti-counterfeiting platform via machine learning.

Solar cell coloration with minimum optical loss is increasingly required for building-integrated photovoltaics (BIPV) in modern urban areas because of its importance in harmonizing the exterior of zero-energy buildings and surroundings. A simple strategy for developing a distributed Bragg reflector (DBR) is designated with 1D lamella-forming polystyrene-b-poly(2-vinylpyridine) (PS-b-P2VP) films. An optimized thermal annealing process produces defect-free lamellar microdomains oriented parallel to the substrate throughout the film. The selective crosslinking in the P2VP block and swelling of these films in a methanol solution with methanesulfonic acid facilitate the formation of highly asymmetric gigantic lamellae, enabling the entire visible-wavelength spectrum of DBR structural colors. Three representative red (R), green (G), and blue (B) DBR films are produced on a Si solar cell. Coloration from high-reflectance and narrow-width DBR films results in vividly colored Si solar cells with a minor or negligible reduction in power conversion efficiency. The approach for photovoltaics, in terms of both the attractive esthetic and technical aspects of BIPV application, offers a viable method for fabricating high-performance DBR films based on block copolymer self-assembly.

The realization of high-performance, anti-fouling optical diffusers is crucial for various light applications. However, this remains a major challenge for conventional diffusers because of the optical inefficiency of multiple scattering and/or surface reliefs vulnerable to contamination. Inspired by the disordered nanostructure of Morpho butterflies that enables the simultaneous fulfillment of wide-angle diffraction, low color dispersion, and superhydrophobic self-cleaning ability due to the lotus effect, this study demonstrates a novel Morpho-type diffuser with high optical performance and anti-fouling properties. Surface nanopatterns of the diffuser are newly designed to realize homogeneous light diffusion, combined with the suitable material selection of polydimethylsiloxane (PDMS) to induce the lotus effect. Consequently, the following properties are simultaneously achieved: i) high transmittance ≈90%; ii) wide-angle diffusion (full width at half maximum ≈80°) with high spatial uniformity; iii) low dispersion; iv) high controllability of anisotropy; and v) anti-fouling properties. Moreover, vi) the applicability of surface protection is demonstrated by exploiting the high flexibility/adhesivity of PDMS. These capabilities surpass other diffusers, and therefore the presented diffuser is promising for a wide range of applications such as lighting, displays, daylight harvesting, optoelectronics, and medicine.

PEPy-COF, a new covalent organic framework (COF), exhibits a shiny blue fluorescence under UV and visible light. In article number 2300412, Amin Zadehnazari, Alireza Abbaspourrad, and colleagues built PEPy-COF via a one-pot condensation reaction using perylene and pyrene building blocks. PEPy-COF features temperature-dependent and solvent-independent fluorescence and a semiconductor band gap making it an excellent candidate for temperature sensing devices.

Herein a class of structurally simple and operationally stable Au(I)-TADF (TADF = thermally activated delayed fluorescence) materials, based on a carbene–metal–amide (CMA) molecular scaffold comprised of sterically bulky N-heterocyclic carbene ligands with N-heterocyclic π-annulation, are reported. These CMA(Au) emitters are thermally stable, adopt coplanar or orthogonal geometry between the carbene and amide ligands, and show strong blue to deep red TADF emissions (466–666 nm) from thermally equilibrated singlet ligand-to-ligand-charge-transfer excited states with emission quantum yields of 0.63–0.99 and radiative decay rate constants of 0.68–3.2 × 106 s−1 in thin film samples at room temperature. The effects of increasing π-extension and orthogonal molecular geometry are similarly manifested in the reduction of both singlet–triplet energy gap and S1 transition dipole moment. The vacuum-deposited Au(I) organic light-emitting diodes (OLEDs) display superior electroluminescence characterized by ultrahigh brightness up to 300 000 cd m−2 and external quantum efficiencies (EQEs) up to 26.2% with roll-offs down to 2.6% at 1000 cd m−2 alongside record-setting device lifetimes (LT95) up to 2082 h. Ultrapure-green TADF-sensitized fluorescent OLEDs employing the CMA(Au) emitter as sensitizer and a multiresonance terminal emitter achieve EQEs of up to 25.3%.

Low dimensional lead-free metal halides have become the spotlight of the research on developing multifunctional optoelectronic materials as their properties show a wide range of tunability. However, most reported low dimensional metal halides only function in the ultra-violet to visible range due to their large bandgap. Moreover, the organic cation based low dimensional metal halides show limited thermal stability; on the other hand, their inorganic cation based counterparts suffer from limited solution processability. A hybrid cation approach is proposed, where a zero dimensional (0D) metal halide ((DFPD)2CsBiI6) is developed by using mixed organic–inorganic cations: 4, 4-difluoropiperidine (DFPD) and cesium (Cs+). This ensures both thermal stability and solution processability. Furthermore, [BiI6]3− octahedra are serving as active light absorption units, which ensures the bandgap to be located at the visible region. Its photoluminescence (PL) is further shifted to the near infrared (NIR) region by doping (DFPD)2CsBiI6 with antimony (Sb3+). The developed materials show multifunctional properties: thermochromic behavior, light detection, and NIR light emitting. This study expands the scope of developing multifunctional 0D metal halides.

Plasmonic nanostructures capable of broadband light trapping and field enhancement have promising applications in a wide range of fields. This study presents a platform for broadband, polarization-independent field enhancement in the visible regime through the use of width-graded nanocavities in a bullseye configuration. The fabrication procedure utilizes electron beam lithography (EBL) to achieve fine control over the nanocavity geometry and template stripping to enable rapid and low-cost production. The utility of these devices as substrates for multi-wavelength surface enhanced Raman spectroscopy (SERS) is demonstrated through molecular detection in a 10 μM solution at two excitation wavelengths. The impact of bullseye geometry on both the broadband spectral response and multi-wavelength SERS performance is examined. The measured SERS enhancement factor (EF) is shown to depend primarily on the plasmonically active surface area of the device, regardless of the local electromagnetic field strength within the nanocavities. These results highlight not only the utility of the width-graded bullseye as a broadband platform for SERS and other applications but also provide design guidelines to optimize the enhancement factor and broadband performance of similar devices.