The type-II semimetal 1T' -MoTe2 is considered a promising candidate for advanced optoelectronic devices due to its unique electronic band structure and distorted lattice configuration. However, its polarizationdependent optical properties have not yet been fully elucidated, and the high dark current due to its semimetal nature inhibits device performance enhancement. This work reports a band-engineered 1T' -MoTe2 /MoSe2 van der Waals heterojunction capable of self-powered, broadband, and polarizationsensitive photodetection. Leveraging the asymmetric Schottky contact at the 1T' -MoTe2 /MoSe2 interface, the device achieves efficient separation of photogenerated carriers, delivering a pronounced photoresponse spanning ultraviolet to near-infrared wavelengths. Under zero bias, it exhibits excellent optoelectronic performance, yielding a responsivity of up to 72.9 mA W-1 and a specific detectivity of up to 3.69 x 108 Jones. Concurrently, the in-plane optical anisotropy of the 1T' -MoTe2 endows the detector with significant polarization sensitivity, achieving a polarization extinction ratio of up to 2.0 under 785 nm. This multifunctionality enables the device to show great potential for applications in polarization-resolved infrared imaging and coded optical communications. Beyond a high-performance photodetector, this work pioneers a strategy for next-generation optoelectronic design by synergizing band engineering with crystal anisotropy in 2D materials. (c) 2025 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Radiative cooling is a passive cooling strategy that dissipates heat externally through the atmospheric window (8–13 μm). This study presents a radiative cooling film with a simple and cost-effective fabrication process. The film was fabricated by mixing SiO₂ hollow microspheres with a UV-curable resin, employing a photopolymerization-induced phase separation method. The resulting gradient refractive index structure enhanced thermal radiation emissivity. At an optimal silica-to-resin mass ratio of 1:1.5 and a film thickness of 1.1 mm, the film achieved a solar reflectivity of 85% and an emissivity of 91% within the atmospheric window. Outdoor experiments conducted in both summer and winter demonstrated stable cooling performance. Under a solar irradiance of 796.9 W/m2 (summer), the film reduced surface temperature by 10 °C compared to ambient air and 20 °C compared to an uncoated glass substrate, achieving a radiative cooling power of 76.7 W/m2. In winter (solar irradiance of 588.8 W/m2), the film maintained a significant cooling effect, though with reduced efficiency due to lower solar exposure. Furthermore, long-term stability tests over six months showed that the film retained high solar reflectivity and infrared emissivity, indicating good durability. Overall, the developed radiative cooling films demonstrate excellent optical properties, structural stability, and cooling efficiency, making it a promising candidate for real-world radiative cooling applications. Further studies on environmental resilience and optimization under diverse climatic conditions are necessary for broader deployment.

As a passive cooling method, radiative cooling is intrinsically energy-efficient and environmentally friendly because it consumes no electric energy and releases no carbon emissions. Smart radiative cooling introduces a new dimension to the current research playground, especially with the use of vanadium dioxide (VO2) to enable passively adaptive temperature-varying response. Here, we propose a temperature-adaptive radiative cooling metasurface based on a two-size VO2 microstructure for broadband absorption in the 8 to 13 mu m atmospheric window, showing a cooling power contrast of similar to 100 W/m(2) around the phase transition temperature. We show the dynamic capability of the next-generation multifunctional and intelligent designs and devices. (c) 2025 Society of Photo-Optical Instrumentation Engineers (SPIE)

Interface engineering in van der Waals heterojunctions is key to optimizing charge dynamics for highperformance optoelectronic and photocatalytic devices. However, the modulation mechanisms of interfacial effects in heterojunctions with different stacking structures remain elusive, which hinders the exploitation and further tailoring of these effects for device applications. This paper systematically investigates the multidimensional modulation of interface engineering in WS2/Bi2Se3 and Bi2Se3/WS2 heterojunctions, highlighting the impact of stacking sequence on interlayer coupling and exciton dynamics. Multidimensional spectroscopic analysis reveals that Bi2Se3/WS2 heterojunction induces stronger interfacial coupling and facilitates interlayer exciton formation, leading to enhanced charge separation and prolonged carrier lifetimes, in contrast to WS2/ Bi2Se3. Compared to WS2, the Bi2Se3/WS2 heterojunction improves photogenerated carrier lifetime by 1800%, providing a new pathway for directional exciton dissociation. The tunable exciton binding energy and charge transfer dynamics are attributed to the distinct roles of interface states. These findings offer mechanistic insights into the design of interface-controlled 2D heterojunctions and provide new strategies for next-generation nanophotonic systems.

Delafossite type oxide CuAlO2 as a highly efficient methanol oxidation reaction catalyst support has been investigated in this work. Utilizing the sustained release of copper from CuAlO2 layered structure, we developed a composite catalyst that was in situ formed PtCu alloy upon oxide via solvothermal method. Owing to the metal-support interaction between PtCu alloy and CuAlO2, abundant oxygen defects and adsorbed hydroxyl groups were generated on the surface of composite catalyst, which were verified by structural characterizations and surface analysis. Density functional theory simulation further revealed that the in situ formation of PtCu alloy accompanied with superficial defects dramatically changed the geometry and electronic structures of the composite catalyst, resulting in a higher mass activity (990 mA/mgPt), specific activity (3.30 mA cm−2 ECSA), and a superior reaction kinetics of MOR performance. This work proves delafossite type oxide CuAlO2 as a potential support to facilitate the anti-CO poisoning ability of Pt-based catalysts.

To improve optical absorbance in the solar spectrum region as well as to reduce solar emittance in the infrared region,a new solar absorber structure based on the double W-SiO2 cermet layers was proposed and optimized. The factors which affect the spectral selectivity of the solar absorber such as the IR reflectance property of metal,and the volume fraction of the absorption layer were investigated. A series of W-SiO2 cermet films with different values of volume fraction were prepared onto Si and K9 glass substrates. The measured optical constants as well as those deduced from the data fitting were used to optimize performance of the selective solar absorber. Based on the optimized parameters,the solar absorber structure with the layer parameter,consisting of that W(similar to 150 nm)/W-SiO2(94 nm,0. 67HVF)/W-SiO2(34 nm,0. 27LVF)/SiO 2(47 nm),was fabricated using a magnetron sputtering system at room temperature. The experimental results agree well with the simulated ones, showing an average optical absorption of 95. 3% in the wavelength region of 250 similar to 1500 nm,and a low thermal emittance of about 0. 124 at 600 K in the broad wavelength region of 0. 25 similar to 25 mu m. Due to the simple components and high efficiency,the solar selective absorber based on the structures consisting of double W-SiO2 cermet layers shows a good potential for practical applications in the future.

Carbon nanotube p-n junction diodes are expected to be the building block of next generation integrated circuits. A p-i-n junction diode was prepared from a SWCNT with one end p-type doped, the other end n-type doped and the middle segment undoped. The p-type doping was performed using triethyloxonium hexachloroantimonate to form an air stable charge transfer complex (SWCNT+-SbCl6-) while polyethylene imine was used as an electron donor for the n-type doping. The device showed an excellent performance with a high rectification ratio of 10(3) and a low reverse saturation current of 23 pA.

An effective soldering process of second-generation coated conductors (CCs) with low joint resistance was presented by using home-made equipment in the present study. The benefit of preprocessing, i.e., polishing, was proved with respect to the reduced joint resistances based on the voltage-current curves. It is revealed that the joint resistance of 10-8 Ω with an overlapping length as short as 2 ...

The octahedral cuprous oxide (Cu2O) supported by reduced graphene oxide composites (Cu2O-RGO) are compounded via a gentle one-pot in situ method. The reduction of GO and the growth of octahedral Cu2O particles simultaneously occur with the Cu2O particles depositing on RGO nanosheets uniformly. The enhanced photocatalytic properties are appraised by decomposition of methyl orange under visible light irradiation. Compared with the pure octahedral Cu2O particles and RGO, the as-prepared composites degrade methyl orange completely within 50 min with apparent rate constant at 82.88 x 10(-3) min(-1), ten times of the pure octahedral Cu2O particles and twenty-seven times of RGO. Scavengers are also introduced to investigate the photocatalytic mechanism which turns out that h(+) and center dot O-2 radicals are the main active species in the photocatalysis process. The synergistic effect between RGO and octahedral Cu2O particles in the photocatalysis process is systematacially analyzed for the first time. Carrier generation occurs on the Cu2O particle, and electron is collected and transported by graphene here to prolong the charge carriers' lifetime, leading to strong absorbance in visible light region, instant carrier separation, and fast charge transfer. Thus the efficiency of visible-light-driven photocatalysis is greatly enhanced. (C) 2017 Elsevier B.V. All rights reserved.

Human telomerase is an endogenous ribonucleoprotein that is over-expressed in most types of malignant cancer cells. Sensitive and specific detection of telomerase activity is crucial for better understanding its role in cancer cells and further exploring its function in cancer diagnosis. Here, we develop convertible DNA ends-based silver nanoprobes for sensitive and specific colorimetric detection telomerase activity. Silver nanoprobes are constructed by modifying telomerase binding substrates (TS) that are pre-hybridized with complementary sequences onto silver nanoparticles (AgNPs), via the coordination between consecutive cytosines in TS strand and AgNPs. This forms blunt-end terminated, double-stranded DNA on the surface of AgNPs. Under the action of telomerase, TS on the silver nanoprobes are elongated with telomeric repeats, converting DNA stiff blunt ends to flexible single-stranded dangling ends. The dangling ends enhance the stability of nanoprobes and relieve their salt-induced aggregation, and the solution shows a yellow color. When telomerase is inactive, the blunt end-terminated nanoprobes cannot resist salt-induced aggregation, resulting in a gray color of solution. Based on telomerase-regulated DNA "blunt-dangling" ends conversion-induced AgNPs' dispersity and color change, colorimetric detection of the endogenous telomerase with AgNPs is realized. The detection limit is equivalent to 1 cell/μL of telomerase activity, and extracts from cancer cells and normal cells are visually distinguished through color difference. The proposed strategy will offer a new approach for reliable, convenient quantification of telomerase activity in biochemical research and clinical diagnosis.

The light-emitting-diode (LED) surface of GaN epilayers grown on Si substrate was irradiated by a femtosecond laser (λ = 800 nm). The morphology of LED surface after laser irradiation was measured by optical microscope and scanning electron microscopy. It was found that many radial cracks appeared in the film on account of thermal expansion and then became more numerous as the number of laser pulses increased. In addition, the changes of the micro structure of GaN and Si substrate were studied by means of Micro Raman Spectroscopy. The results showed the presence of polycrystalline silicon and the decomposition of GaN had taken place in the laser spot or the region with the large laser fluence. Comparatively, in the areas with the low laser fluence or the edge of laser spot, the characteristic peaks of GaN films and the AO phonon peak of Si had an obvious blueshift, which most likely was the result of compressive stress between GaN layers and Si substrate. The maximum values of the compressive stress were 0.74 GPa and 1.4 GPa, respectively. Furthermore, with the increase of the laser fluence, the original Si crystalline structure recovered gradually. The above study showed that the stress, the transformation and the deformation play a predominant role in the femtosecond laser etching process of LED.

Biosynthesis of gold nanostructures has drawn increasing concerns because of its green and sustainable synthetic process. However, biosynthesis of gold nanoplates is still a challenge because of the expensive source and difficulties of controllable formation of morphology and size. Herein, one-pot biosynthesis of gold nanoplates is proposed, in which cheap yeast was extracted as a green precursor. The morphologies and sizes of the gold nanostructures can be controlled via varying the pH value of the biomedium. In acid condition, gold nanoplates with side length from 1300 ± 200 to 300 ± 100 nm and height from 18 to 15 nm were obtained by increasing the pH value. Whereas, in neutral or basic condition, only gold nanoflowers and nanoparticles were obtained. It was determined that organic molecules, such as succinic acid, lactic acid, malic acid, and glutathione, which are generated in metabolism process, played important role in the reduction of gold ions. Besides, it was found that the gold nanoplates exhibited plasmonic property with prominent dipole infrared resonance in near-infrared region, indicating their potential in surface plasmon-enhanced applications, such as bioimaging and photothermal therapy.

Photovoltaic devices show promising applications in detection and energy fields as well as in next-generation optoelectronic circuits. The use of the ideal photosensitive material and device design are critical for achieving a high-performance photovoltaic device. Here, an intramolecular p-i-n junction photovoltaic device based on selectively doped carbon nanotubes is investigated. In this kind of device, the opposite ends of an individual single-walled carbon nanotube (SWCNT) channel are doped selectively by triethyloxonium hexachloroantimonate (OA) and polyethylene imine (PEI) to obtain stable p- and n- type SWCNT segments respectively, while the middle segment of the SWCNT is kept intrinsic, causing the formation of an intra-tube p-i-n junction for the efficient separation of photogenerated electron-hole pairs. The optical-absorption and electrical testing demonstrate that the OA and PEI can dope the SWCNTs into the stable p- and n- types, respectively. In the dark, the prepared p-i-n junction device behaves as a diode with a high rectification ratio >103 that can be tuned by the gate voltage. Under a 1550-nm monochromatic illumination, the device exhibits a good photovoltaic effect with a large open-circuit voltage of 0.41V and an external power conversion efficiency of ~4.2%. The quantum efficiency of the device is estimated to be as high as ~73%.

Laser-induced periodic surface structures (LIPSS) were processed on the TiO2 bulk surface under the irradiation of 248 nm unpolarized KrF excimer laser pulses in air. Spatial LIPSS periods ranging from 2 to 3.5 μm are ascribed to the capillary wave. These microstructures were analyzed at different laser pulse numbers with the laser energy from 192 to 164 mJ. The scanning electron microscopy results indicated eventually stripes that have been disrupted as the increase in the laser pulse numbers, which is reasonably explained by the energy accumulating effect. In addition, investigations were concentrated on the surface modifications at pre-focal plane, focal plane and post-focal plane in the same defocusing amount. Compared with condition at pre-focal plane, in addition to the plasma produced at target, the air was also breakdown for the situation of post-focal plane. So it was reasonable that stripes appeared at pre-focal plane but not at post-focal plane.

A p-i-n junction diode constructed by the locally doped network of single-walled carbon nanotubes (SWNTs) was investigated. In this diode, the two opposite ends of the SWNT-network channel were selectively doped by triethyloxonium hexachloroantimonate (OA) and polyethylenimine (PEI) to obtain the air-stable p- and n-type SWNTs respectively while the central area of the SWNT-network remained intrinsic state, resulting in the formation of a p-i-n junction with a strong built-in electronic field in the SWNTs. The results showed that the forward current and the rectification ratio of the diode increased as the doping degree increased. The forward current of the device could also be increased by decreasing the channel length. A high-performance p-i-n junction diode with a high rectification ratio (~10(4)), large forward current (~12.2 μA) and low reverse saturated current (~1.8 nA) was achieved with the OA and PEI doping time of 5 h and 18 h for a channel length of ~6 μm.

A p-i-n junction diode based on the selectively doped single-walled carbon nanotube (SWCNT) had been investigated, in which two opposite ends of individual SWCNT channel were doped into the p- and n-type SWCNT respectively while the middle segment of SWCNT was kept as the intrinsic. The symmetric and asymmetric contacts were used to fabricate the p-i-n junction diodes respectively and studied the effect of the contact on the device characteristics. It was shown that a low reverse saturation current of ~20 pA could be achieved by these both diodes. We found that the use of the asymmetric contact can effectively improve the performance of the p-i-n diode, with the rectification ratio enhanced from ~10(2) for the device with the Au/Au symmetric contact to >10(3) for the one with the Pd/Al asymmetric contact. The improvement of the device performance by the asymmetric-contact structure was attributed to the decrease of the effective Schottky-barrier height at the contacts under forward bias, increasing the forward current of the diode. The p-i-n diode with asymmetric contact also had a higher rectification ratio than its counterpart before doping the SWCNT channel, which is because that the p-i-n junction in the device decreased the reverse saturated current.

A reversed phase ultra performance liquid chromatography. mass spectrometric method was developed for the separation and analysis of triglycerides in edible oils. The samples were separated by using three ultra performance C-18 columns in series with a total length of 40 cm (10 cm + 15 cm + 15 cm) at high pressure with acetonitrile. isopropanol (50; 50, V / V) as mobile phase at a flow rate of 0. 2 mL/min and at col. umn temperature of 25 degrees C, and detected by APCI ionization. mass spectrometry. The edible oil sample was dis. solved in isopropanol and injected in LC. MS directly. The triglycerides in edible oils were distinguished to their better fine components which included corn oil, peanut oil, sunflower seed oil, rice oil, olive oil, sesa. me oil and soybean oil. The chromatograms of different edible oils showed that the same kind of edible oil was composed of similar triglyceride composition and content, while the different kind of edible oils differed. The experimental result showed that the method could be use for identifying 5% lard adulterated in soybean oil. The method suggests a significant research way for identifying adulteration in edible oil.

Water-soluble upconversion nanoparticles (UCNPs) were prepared by a one-pot procedure in a two-phase reacting system. Four kinds of surfactants were tested in the synthesis process as capping agent to tune size and morphology of nanocrystals. Nanoparticles (approximately 70 nm) and rods (400 nm and 2.5 μm) were synthesized, respectively. Then, Fourier transform infrared spectroscopy analysis confirmed the successful linking between UCNP surface and surfactant. Ionic liquids (ILs) and surfactants participated in synthesis process together, competing with each other to cap on UCNPs. ILs still led the competition of capping, while surfactants worked as cooperative assistants to develop functional surface. Further characterizations such as high-resolution transmission electron microscopy and X-ray diffraction indicated the changes in crystallization and phase transformation under the influence of surfactants. In addition, the growth mechanism of nanocrystals and upconversion fluorescence luminance was also investigated in detail. At last, the cytotoxicity of UCNPs was evaluated, which highly suggest that these surface-functionalized UCNPs are promising candidates for biomedical engineering.

Upconversion nanocrystals with small size and strong fluorescent signals own great potential in applications such as biomolecule-labeling, in vivo tracking and molecular imaging.Herein we reported that NaYbF 4 : 25%Gd, 2%Tm upconversion nanocrystals with small size and strong fluorescent signals were controllably synthesized by oleic acid (OA)/ ionic liquid (IL) two-phase system for targeted fluorescent imaging of gastric cancer in vivo.The optimal synthesis condition of NaYbF 4 : 25%Gd, 2%Tm upconversion nanocrystals by OA/IL two-phase system was established, adding more metal ion such as Na + ion could facilitate the size control and crystal-phase transition, more importantly, markedly enhancing fluorescent intensity of beta-phase nanocrystals compared with traditional methods.Alpha-phase NaYbF 4 , 2%Tm upconversion nanocrystals with less than 10nm in diameter and beta-phase NaYbF 4 : 25%Gd, 2%Tm upconversion nanocrystals with 30 nm or so in diameter and strong fluorescent signals were obtained, these synthesized nanocrystals exhibited very low cytotoxicity.Folic acid-conjugated silica-modified beta-phase NaYbF 4 : 25%Gd, 2%Tm upconversion nanocrystals were prepared, could actively target gastric cancer tissues implanted into nude mice in vivo, and realized targeted fluorescent imaging.Folic acid-conjugated silica-modified NaYbF 4 : 25%Gd, 2%Tm upconversion nanocrystals show great potential in applications such as targeted near infared radiation fluorescent imaging, magnetic resonance imaging and targeted therapy of gastric cancer in the near future.

Molecular imaging is developing fast towards multi-modality and simultaneous therapy. For molecular imaging, upconversion nanoparticles (UCNPs), especially lanthanide-doped nanocrystals own obvious advantages such as low toxicity, large Stokes shifts, high resistance to photo-bleaching and photochemical degradation. Moreover, near infrared (NIR) excitation contributes to the auto-fluorescence minimization, a larger penetrating depth, and less harmfulness to cells compared with traditional ultraviolet (UV) excitation. On the other hand, the composites of UCNPs with biological target molecules exert superior performance, broadening their biological application scope from multi-modality imaging, to simultaneous drug delivery and targeted therapy. Herein, we review main advances of UCNPs applied to tumor multi-modality imaging and simultaneous therapy over the past few years, explore their application prospects, and discuss the concepts, issues, approaches, and challenges, with the aim of improving the application of UCNPs in biomedical imaging and therapy in near future.