Ultraviolet Range Research Articles

Photoinduced Charge Injection from Shallow Point Defects in Diamond into Water.

Thanks to its low or negative surface electron affinity and chemical inertness, diamond is attracting broad attention as a source material of solvated electrons produced by optical excitation of the solid-liquid interface. Unfortunately, its wide bandgap typically imposes the use of wavelengths in the ultraviolet range, hence complicating practical applications. Here, we probe the photocurrent response of water surrounded by single-crystal diamond surfaces engineered to host shallow nitrogen-vacancy (NV) centers. We observe clear signatures of diamond-induced photocurrent generation throughout the visible range and for wavelengths reaching up to 594 nm. Experiments as a function of laser power suggest that NV centers and other coexisting defects─likely in the form of surface traps─contribute to carrier injection, though we find that NVs dominate the system response in the limit of high illumination intensities. Given our growing understanding of near-surface NV centers and adjacent point defects, these results open new perspectives in the application of diamond-liquid interfaces to photocarrier-initiated chemical and spin processes in fluids.

Screening the structural, optoelectronic and thermoelectric features of novel inverse perovskites X3MgNa (X= Cl, Br and I): A theoretical investigation

The structural, optoelectronic, and transport features of novel X3MgNa (X = Cl, Br, and I) antiperovskites compounds are revealed by using the density functional theory. The structural stability of all of the compounds under consideration has been verified by using the Birch-Murnaghan equations of states, which indicate that all compounds have structural stability due to ground-state energy levels being negative. The electronic band structure and TDOS results reveal that the electronic band gap of Cl3MgNa is 4.22 eV, Br3MgNa is 2.18 eV, and I3MgNa is zero eV. The partial density of state PDOS results demonstrate that the formation of the conduction and valence bands is due to the hybridization of Cl-3p, Br-4p, Na-3p, and I-5p states. In terms of optical results, reverse perovskite with Br as a cation has shown much better optical conductivity in the ultraviolet range. Therefore, Br3MgNa is a potential candidate among all the compounds for optoelectronic-based applications. The Boltztrap code, which is patched with WEIN2K code, has been used to compute the thermoelectric characteristics of the examined compounds. Br3MgNa has a greater power factor, a high electrical conductivity, and a figure-of-merit; ZT approaches unity, indicating a promising option for thermoelectric applications.

A comprehensive first-principles investigation of structural, electronic, vibrational, optical, thermodynamic and thermoelectric properties of LiZnAs

The structural, electronic, vibrational, optical, thermodynamic and thermoelectric properties of Nowotny–Juza filled tetrahedral semiconductor LiZnAs under high pressure is investigated using the plane-wave pseudo-potential approach in the frame work of density functional theory (DFT) within the generalized gradient approximation (GGA). The calculated lattice constant (a0) and bulk modulus (B0) at ambient pressure are consistent with earlier reported experiment and theoretical results. The variation in Lattice constant, Bulk modulus (B0), Young modulus (Y), Shear modulus (G), Elastic anisotropy factor (A), Poission ratio (μ), Paugh (B/G) ratio and Elastic constants with pressure is analyzed and concluded. Electronic band structure calculations reveal that with applied pressure direct band gap increases and the indirect band gap decreases. Thermodynamic properties reveals thermodynamically stability with pressurize conditions. The real and imaginary parts of the Dielectric function (ε), Refractive index (η), Extinction Coefficient (k), Optical Conductivity (s), Electron/Optical Energy Loss Function (L), Absorption Coefficient (α), Reflectivity (R) at different pressure conditions are correspondingly studied. With applied pressure the absorption spectra shows a blue shift which makes LiZnAs as potential candidates for the application of optoelectronic devices in ultraviolet frequency range. The thermoelectric properties like Seebeck coefficient (S), Electrical conductivity (σ), and Electronic thermal conductivity (k) and Power factor (PF) have been studied as a function of temperature and chemical potential. Positive value of calculated Seebeck coefficient with temperatures ensures the p-type semiconducting nature of LiZnAs. Results provides theoretical guidance for future experimental investigations and industrial applications of LiZnAs.

Transparent Luminescent down-conversion coating for improved performance and enhanced stability of carbon-based perovskite solar cells

Methylammonium lead halide-based perovskite solar cells (PSCs) perform superior photovoltaic performance, nevertheless, demonstrate limited light utilization and instability within the ultraviolet (UV) range. Lanthanide-based down-conversion (DC) materials can mitigate the photoinduced deterioration by resolving spectrum mismatched losses. Particularly, lanthanide complexes possess a broad UV absorbing region thus can convert absorbed UV light to visible or near-infrared light, exhibiting large pseudo-Stoke's shift while they could allow spectrum responsiveness of the PSCs in the UV.Therefore, the DC material may enhance the photovoltaic performance by converting high-energy photons to low-energy photons whilst may also perform as UV shielding material, and finally may both develop PSCs' efficiency and stability. Herein, a novel transparent luminescent down-converting layer (LDC) based on a highly emitting Europium complex in a siloxane matrix was used as an external coating to PSCs with the purpose of improving the solar cells' performance extending their response in the UV region while improving cells’ photostability. The conducted studies indicated that the LDC coating may additionally serve as an anti-reflective and UV-shielding layer simultaneously, resulting in better light-harvesting ability of the perovskite. As a result, short circuit current (Jsc) amplification by the presence of LDC re-emitting the absorbed UV light to the visible and the best carbon-based perovskite solar cell (C-PSC) revealed a 16.13 % overall performance in comparison to the 15.38 % obtained for the control device. Furthermore, photostability tests demonstrated that the unencapsulated LDC-modified devices prepared under ambient conditions retained 75 % of their initial PCE after 8 h under artificial solar light illumination whereas the control devices remained at 40 % at the same conditions. These findings suggest that the LDC layer decreases the UV degradation for PCEs, resulting in PCE and stability enhancement.

The use of low-level lasers in the treatment of oral lichen planus (OLP) – a review of the literature

A laser is a device that emits radiation in the visible light, ultraviolet or infrared range, using the phenomenon of forced emission. The name is an acronym for Light Amplification by Stimulated Emission of Radiation. The main characteristics of a laser beam include: monochromaticity, coherence, parallelism and intensity. By power, we can divide lasers into 2 groups: high-energy (hard) lasers with emission power above 1 W and low-energy (<1 W) lasers. Lasers are used in medicine, industry, military technology, telecommunications, surveying and construction, among other fields. Lichen planus is a chronic disease of the mucous membranes and skin with a fairly common occurrence, characteristic clinical picture and unclear etiology. The therapy of lichen planus of the mucous membranes, especially its oral form (OLP), is still a major problem despite continuous medical advances. To date, a fully effective treatment regimen has not been developed. Current methods are mainly based on pharmacotherapy. With advances in technology, the search for alternative forms of treatment has begun. In recent years, an increasing number of reports have suggested the validity of using Low Level Laser Therapy (LLLT) to treat oral lichen planus. The use of this treatment may reduce the incidence of side effects observed with traditional corticosteroid (CS) therapy, sulfones or immunosuppressants.

Revisited UV- spectra of chlorohydroxoaurate anions

The most important ionic precursor of gold, [AuCl4]-, is used in aqueous solution leading to chlorohydroxoaurates species, [AuCl4-x(OH)x]- (x = 1–4) due to partial hydrolysis. Their UV spectral signatures are still relatively unknown though very useful in many domains of application. Individual spectra of each of them are determined for the first time thanks to a thorough experimental investigation comprising the range 200–250 nm, surpringly ignored up to now. New isosbestic points useful for species partition analysis are evidenced. Electronic transition attribution is obtained from quantum chemical calculations based on TD-DFT. The prediction of the experimental blueshifted bands of the [AuCl4-x(OH)x]-1 anions was possible only after applying energy corrections calibrated on the full UV range two-band spectrum of the [AuCl4]- complex.

Natural and polyanionic heparin polysaccharide functionalized upconversion nanoparticles for highly sensitive and selective ratiometric detection of pesticide

Pesticide contamination is a global concern, threatening human health and food safety. Herein, we developed heparin (HEP) functionalized upconversion nanoparticles (UCNPs)-based ratiometric nanosensor for the sensitive detection of 2,6-dichloro-4-nitroaniline (DCN) pesticide via inner filter effect. The strategy for HEP functionalization of UCNPs is based on adjusting the surface potentials of UCNPs with polyanionic HEP through the electrostatic interaction. UCNPs (NaYbF4:Gd/Y/Tm@NaYbF4@NaYF4) was designed with core-shell-shell structure and extra sensitizer layer for efficient and strong upconversion luminescence (UCL) in the range of UV to NIR. After incorporation of DCN, the upconverted UV emission of UCNPs-HEP ratiometric nanosensor was considerably quenched with the NIR UCL at 800 nm remaining unchanged as internal standard. The UCNPs-HEP ratiometric nanosensor can achieve outstandingly selective and sensitive detection of DCN at the wide linear range of 5–300 μM with a detection limit of 0.41 μM. The remarkable applicability of the UCNPs-HEP ratiometric nanosensor was verified in apple, cucumber and grapes samples. The developed UCNPs-HEP ratiometric nanosensor with excellent biocompatibility and water dispersion capability, is promising for convenient, selective and sensitive sensing of DCN towards food and aqueous samples.

Validated Area Under Curve Quantitative UV Spectrophotometric Analysis of Rebamipide in Drug Formulations

A very simple, accurately perfect, precisely repeatable procedure has been proposed for the estimate of rebamipide in medicines. Evaluation of previous works indicates the fact that, so far no UV spectrophotometric scheme for quantifiable estimate by area under curve technique for the drug rebamipide is not described. Therefore, there was a need to plan a different methodology to analyze the medicine employing dimethyl formamide in the form of solvent. This medication monitors Beer’s law in the range of concentration 20 to 200 ìg/mL in the ultraviolet range, particularly areas between 320 and 340 nm for are under curve because the absorption maximum was found to be 330 nm in the selected solvent. The recovery readings proved the offered technique’s accuracy and outcomes were authenticated par accordance with the International Council for Harmonisation (ICH) references. The discoveries were reasoned to be consistent as well as agreeable. As a consequence, this optional technique was successfully used to estimate rebamipide quantitatively in conventional analytical applications.

Harnessing synergistic effects in GQD@Pt(II) nanocomposites for enhanced photovoltaic performance: a computational study.

The development of efficient solar energy conversion technologies is crucial for addressing global energy challenges and reducing reliance on fossil fuels. Platinum(II) complexes are promising materials for photovoltaic applications due to their strong light absorption and long-lived excited states. However, their narrow absorption in the visible spectrum and stability issues limit their performance. Combining platinum(II) complexes with graphene quantum dots (GQDs) can enhance photovoltaic performance by leveraging the complementary light harvesting and charge transfer characteristics of the two components. This study utilizes density functional theory (DFT) calculations to explore their electronic structures, charge transfer dynamics, and photoelectric performance. Specifically, it investigates the effects of incorporating different substituents, either electron-donating or electron-withdrawing, onto the fluorene motif of the Pt(II) complex. The findings reveal that combining GQDs with Pt(II) complexes extends light absorption into the UV range, enabling comprehensive solar utilization. Upon photoexcitation, electrons migrate between the GQD conduction band and the Pt(II) complex, stabilizing charges and enhancing extraction. Substituents significantly influence charge transfer dynamics: electron-withdrawing groups promote transfer to the GQD, while electron-donating groups encourage charge separation and delocalization. Nanocomposites featuring electron-donating substituents achieve the highest energy conversion efficiencies, with GQD@Pt(II)-NPh2 reaching 24.6%. This is attributed to improved light harvesting, efficient charge injection, and reduced recombination. These insights guide the rational design of GQD-Pt(II) nanocomposites, optimizing charge separation and transfer processes for enhanced photovoltaic performance. The computational approach employed here provides a robust tool for developing advanced materials in renewable energy technologies. The computational studies reported in this work were performed using the DFT approach, specifically employing the hybrid functional PBE0. The PBE0 functional's accuracy in describing electronic structures and excited-state properties is essential for understanding charge transfer processes, photoabsorption, and emission characteristics in metal-organic complexes. Geometry optimizations and time-dependent DFT (TD-DFT) calculations were carried out to investigate the properties of the nanocomposites. The effects of solvents were replicated using the conductor-like polarizable continuum model (CPCM). The charge transfer length (ΔL) and interfragment charge transfer (ΔQ) were calculated using the Multiwfn software package, and all calculations were performed using the BDF software package.

The electronic and optical properties of graphdiyne modulated by adsorption of lithium: A first-principles calculation

To explore a novel two-dimensional semiconductor material with tunable bandgap, the adsorptive, electronic, and optical behaviors of lithium (Li) adsorption on graphdiyne (GDY) are studied by employing density functional theory based on first-principles calculations. The results demonstrate that Li adsorption on GDY exhibits high adsorption energy and a proper migration energy barrier, both of which are favorable for facilitating Li adsorption and desorption. Upon Li adsorption, charge transfer occurs from Li to C atoms along the C chain containing alkyne bonds, transforming the systems from p- to n-type semiconductors with the band gap decreasing slightly. Notably, the flexible adsorption/desorption capability of Li on GDY enables an adjustable and reversible change of decreasing/increasing the band gap through the change of the external field. Meanwhile, Li migration primarily occurs between the equivalent A sites, preserving the stable semiconductor characteristics of the system during the Li migration process. Additionally, the absorption coefficient and reflectivity for GDY with Li adsorption decrease in the infrared and visible regions, while maintaining high in the near ultraviolet range. In summary, GDY is not only a promising candidate for fast-charging/discharging Li-ion batteries, but also provides innovative valuable insights for applications in tunable optoelectronic devices.

The adsorptive, electronic, magnetic and optical performances of lithium-adsorbed 2D graphdiyne-like B–N–C compound: A first-principles calculation

A novel two-dimensional graphdiyne (GDY)-like B–N–C compound (BNDY) is designed. The investigation of the adsorptive, electronic, magnetic, and optical properties of lithium (Li) on BNDY reveals several intriguing discoveries. BNDY exhibits slightly lower Li adsorption energy and smoother diffusion barriers than GDY, suitable for rapid Li mobility. Following the adsorption of Li, charge transfers from Li to B, N, and C atoms along the C chain containing alkyne bonds, ultimately transforming the systems from p-to n-type semiconductors. Notably, it also induces a spin-splitting phenomenon, resulting in the generation of magnetic moments. Moreover, the absorption coefficient and reflectivity of BNDY with Li adsorption decrease in the infrared and visible regions, while maintaining high in the near ultraviolet range. In conclusion, BNDY is suitable for fast-charging/discharging Li-ion batteries, and Li adsorption plays an important role in modulating BNDY's properties, providing a theoretical foundation for applications in spintronic and optoelectronic devices.

Robust Deep UV Photodetectors Based on One‐Step‐Grown Polycrystalline Ga2O3 Film via Pulsed Laser Deposition toward Extreme‐Environment Application

AbstractGallium oxide (Ga2O3), with an ultrawide bandgap corresponding to the deep ultraviolet (DUV) range, has attracted significant attention in optical filter‐free photodetectors. In practical terms, DUV photodetectors employed in extreme conditions, for example, flame detection and space exploration, face the challenges of performance degradation caused by high/low‐temperature transformation. Here, DUV photodetectors are tailored with high durability and stability by one‐step‐grown β‐Ga2O3 films via pulsed laser deposition. A high‐oxygen‐pressure scheme effectively addresses the issue of film‐free deposition at specifically high temperatures, facilitating the formation of polycrystalline high‐resistivity β‐Ga2O3 films. As a result, the devices exhibit outstanding performance, including a low dark current (4.4 pA @30 V), high photoresponsivity (147.36 A W−1), and fast response time (3.1/22.6 ms). Additionally, the photoresponse performance shows minimal degradation at high temperatures up to 300 °C and even improves at low temperatures down to −100 °C, ranking it among the most robust DUV photodetectors. The mechanism of photoresponse, involving the exciton formation, bandgap evolution, carrier‐phonon scatter, etc., is also elucidated in a wide temperature range. This work provides an efficient solution for developing robust Ga2O3 DUV photodetectors with excellent performance for extreme‐condition applications.

A novel algorithm to extrapolate ultraviolet absorption of chromophoric dissolved organic matter from remote sensing ocean color

Accurate estimation of the absorption of chromophoric dissolved organic matter (CDOM) in ultraviolet (UV) wavelength range is crucial for understanding photochemical and biochemical processes in the global ocean. Here, we propose a novel UV absorption extrapolation (UVAE) algorithm. It extrapolates the absorption coefficients (ag(λ) where λ is the wavelength in nm) of CDOM in the UV wavelength range from ocean color data in the visible wavelength range observed by satellite remote sensing. The extrapolation is based on the assumption that three characteristic Gaussian bands describe the CDOM UV–visible absorption spectra (275–443 nm). The UVAE algorithm retrieves the ag(275), ag(295), ag(330), and ag(380) using the characteristics of the spectral slope (S) of the absorbance spectra of CDOM at specific wavelength intervals, namely 275–295, 295–330, 330–380, and 380–443 nm. With the UVAE algorithm, the spatial variability of CDOM spectral features can be captured on a global scale using data from the Moderate-resolution Imaging Spectroradiometer (MODIS) Aqua mission. The retrieved ag(275), ag(295), ag(330), and ag(380) values match well with in-situ observed values, with mean absolute percent differences (MAPDs) of 19.2 %, 26.1 %, 36.9 %, and 46.6 %, respectively. The performance of the UVAE algorithm demonstrates a significant improvement compared to that of existing algorithms, especially for ag(λ) at lower wavelengths.

Red and green fluorescent carbon dots for highly effective ultraviolet radiation screening and sensing

Carbon dots (CDs) have attracted intense attention because of their excellent optical properties, low toxicity, and biocompatibility. CDs have a great potential to be used as fluorescent sensors and ultraviolet (UV)-blocking materials. In this research, CDs were synthesized by the hydrothermal method using mangosteen leaves as a precursor. A CD aqueous solution exhibited bright green (G-CDs) and red (R-CDs) fluorescence with naked-eye observation under UV irradiation. The maximum fluorescence emission peak intensities of G-CDs and R-CDs were observed at 312 nm and 671 nm under excitation wavelengths of 275 nm and 410 nm, respectively. The absorbance spectra of CDs are shown in the UV range of 200–400 nm. The transmission spectra indicate that the G-CD solution screens UVB and UVC, while R-CDs are an excellent block for all UVA, UVB, and UVC. The average UV-shielding efficiencies of R-CDs and G-CDs are 97.4 %, and 56.1%, respectively. Furthermore, the R-CDs have a tendency to screen high-energy blue light. FTIR results display functional groups of organic substance on CD surfaces showing that the CDs have good biocompatibility with organics and biological materials. Moreover, nanocomposite films of CDs and polyvinyl alcohol (PVA) polymer (CDs/PVA) were prepared using a drop-casting method. In the polymerized state, R-CDs/PVA and G-CDs/PVA exhibit significant improvements in average UV ray blockage of 100.0%, and 83.8% enhancement, respectively. It is noteworthy that PVA combined with R-CDs achieves complete UV ray blocking. Furthermore, the emissions from both CD solution and CDs/PVA under UV radiation cover the regions of red, green, and blue emission. Hence, this work demonstrates the performance of R-CDs- and G-CDs-based platforms that show a high potential for UV-shielding and sensing applications.

Empirical analysis of a hollow cathode’s intensity distribution in the vacuum ultraviolet range

Empirical analysis of a hollow cathode’s intensity distribution in the vacuum ultraviolet range

The “invisible light”: Tracing its journey from scientific history to physics teaching

The history of science in teaching has been the subject of much discussion, analysis, practices and educational evaluations in recent decades. The objective is to present an important historical process of physics in the 19th century and to discuss its use and contribution to the understanding of the electromagnetic spectrum. The first part of the work describes the main experiments that led to the confirmation of the existence of 'invisible light', that is, radiations in the infrared and ultraviolet range. The second part explores how one of the original experiments concerning infrared radiation can be used to demonstrate and discuss the existence of radiation outside the visible spectrum. The proposal of the work is that these two dimensions, the historical approach and the accomplishment of pertinent experiments, are concatenated in the didactic exploration of this important content: the meaning of the unified electromagnetic spectrum and its important applications in people's daily lives.

Influence of WO3 replacement for CaO on physical, optical, and γ-ray protection properties of borotellurite glasses: A comparative study

Glasses with WO3 in place of CaO with the chemical formula 45B2O3+15TeO2+(18-X)CaO+22Na2O + XWO3: X = 0 (W-0), 1.5 (W-1.5), 3 (W-3), 4.5 (W-4.5), and 6 (W-6) mol% were prepared using the melt quenching method. A comprehensive study of the structural, physical, optical, and γ-ray protection properties of the prepared glasses was investigated. Density (ρ), molar volume (Vm), UV–Vis measurements, the MCNP5 simulation code, and PhX software were employed to achieve the aims of this study. The density (ρ) of the W-X samples increased slightly from 2.45 g/cm3 to 2.62 g/cm3 as WO3 content increased from 0 to 6 mol%. The molar volume (Vm) evinced the same trend as ρ. In the UV range, significant absorption was observed, rising as the molar concentration of WO3 increased. The direct optical gap (Eopt.(dir.)) declined from 3.59 eV to 3.24 eV, while the indirect gap (Eopt.(indir.)) declined from 3.27 eV to 2.36 eV. The Urbach energies (ΔE) ranged from 0.35 to 0.71 eV. The refractive index (n) increased from 2.33 to 2.59 as WO3 content increased. The molar polarizability (αm) and molar refractivity (Rm) increased. The linear-attenuation absorption (μ) order is: W-0 < W-1.5 < W-3 < W-4.5 < W-6. The W-6 glass sample possessed the lowest half- (HVL), and tenth- (TVL) value layer, as well as the lowest mean free path (MFP). Therefore, the W-6 glass sample offers the best gamma radiation shielding capability among the prepared W-X glasses. Within the investigated energy range, the effective atomic number (Zef) varied from 30.773 to 13.234, 35.398–13.969, 39.089–14.670, 42.103–15.338, and 44.611–15.977 for the W-0, W-1.5, W-3, W-4.5, and W-6 glasses, respectively. At 0.080 MeV, the mass-attenuation absorption (μm) of the investigated W-X glasses was higher than for TBLMC-X (TeO2–B2O3–Li2O–MoO3–CuO) and TS-X (9SiO2–Al2O3–Na2O–B2O3–TeO2) glasses.

Sb2O2SeO3 and Sb2O(SeO3)2: Two-Layered Antimony(III) Selenites with Enhanced Birefringence.

Two antimony selenites, Sb2O2SeO3 and Sb2O(SeO3)2, were synthesized by simultaneously incorporating stereochemically active lone pair electrons containing SeO32- and Sb3+. These compounds are structured with [SbOx] polyhedra and [SeO3] units within a two-dimensional framework. Both of them exhibit cutoffs at 300 and 330 nm within the ultraviolet (UV) range and demonstrate significant birefringence, with indices of 0.069 and 0.126 at 546 nm, respectively. These properties highlight their potential as UV birefringent materials. Structural analyses and theoretical calculations reveal that their exceptional birefringence results from the synergistic interactions between SeO32- anions and Sb3+ cations.

Characterizations of two-photon absorption process induced by defects in aluminum nitride using Z-scan method

In this work, we reported two-photon absorption (TPA) measurements for aluminum vacancies in Aluminum nitride single crystals. We measured the linear transmission and identified the defect levels. Using the Z-scan method, we measured the TPA coefficients of the transitions between defect levels from 380 nm to 735 nm. The transition occurs between the aluminum vacancies defect levels. Furthermore, the power dependence shows good linear fitting, confirming the TPA mechanism. These results will be helpful for the design and fabrication of ultra-low loss waveguides and integrated photonics in the ultraviolet spectral range.

Dual-drive strategy-based modulation of the interfacial charge of S-scheme heterojunction and photoelectrochemical ultrasensitive detection of CD44

The efficacy of charge carrier separation plays a crucial role in influencing the practical application of photoelectrochemical (PEC) detection platforms, which can be meticulously engineered to realize highly sensitive detection at the sensing interface. Hence, a novel dual-drive strategy was proposed to integrate thermally-assisted external drive behavior with the internal drive behavior of sulfur vacancies (SVs), realizing the rapid separation of charge at the S-scheme heterojunction sensing interface. On the one hand, unabsorbed solar energy was utilized an external driving force to facilitate efficient photothermoelectric conversion within the In2S3/CdS heterojunction, achieving the photocurrent response intensity 1.5 times higher than conventional PEC detection methods. On the other hand, introducing sulfur vacancies (SVs) as internal driving forces induced ordered migration and directional flow of charge carriers. Moreover, density functional theory (DFT) calculations and experimental results demonstrated that photo-generated carriers achieved rapid separation along the S-scheme heterojunction. Under the optimal conditions, a biosensor constructed based on the dual-drive strategy exhibited high sensitivity for the CD44 (cluster of differentiation-44) cluster, with a low detection limit of 0.132 pg mL−1and a wide linear range of 0.001 ∼ 1000 ng mL−1. The proposed strategy offers new insights into how to effectively harness excess energy in the traditional ultraviolet spectral range for ultrasensitive biosensors.