Luminescent Lanthanide Research Articles

Halogen-Bonds-Based Strategy for the Design of Highly Luminescent Lanthanide Coordination Polymers as Taggants for Plastic Waste Sorting.

Reactions in water between a lanthanide ion and 3,4,5,6-tetrachloro-phthalate lead to a new series of iso-structural coordination polymers with general chemical formula [Ln2(tcpa)3(H2O)6]∞ with Ln = Eu-Yb plus Y. The crystal structure has been solved on the Y-derivative. This compound crystallizes in the monoclinic system, space group P21/n (no. 14) with the following cell parameters: a = 6.2155(2) Å, b = 19.6652(7) Å, c = 30.3720(9) Å, β = 94.631(1)°, V = 3700.22(37) Å3, and Z = 4. Luminescence properties of homo- and heterolanthanide coordination polymers that belong to this structural family have been studied in detail. This study shows that, in this system, intermetallic energy transfers are very efficient and that dilution by an optically non active Gd3+ ion leads to quite efficient luminescent heterolanthanide coordination polymers. The luminescence of these compounds, dispersed at a low doping rate in a poly(methyl methacrylate) (PMMA) matrix, can be observed even with the naked eye. This study opens the way to the use of such compounds as taggants for optical sorting of plastic waste and consecutive recycling.

Efficiency enhancement of photovoltaic cells under infrared light irradiation by synergistic upconversion luminescence of NaYF4:Yb3+/Er3+/Tm3+@TiO2-CQDs

Rare-earth doped upconversion luminescence (UCL) is of great significance in improving the utilization of infrared (IR) light from solar radiation, especially in the efficiency enhancement of photovoltaic (PV) cells. However, the low level of luminescence efficiency remains a great challenge. Here, we designed NaYF4:Yb3+/Er3+/Tm3+@TiO2-CQDs upconversion luminescent materials. The construction of the core–shell structure and the loading of carbon quantum dots (CQDs) resulted in a 9-fold enhancement of upconversion luminescence and a 3.02% enhancement of the efficiency of the photovoltaic cell. These data indicate that the construction of the core–shell structure can effectively inhibit the surface quenching of the luminescent particles, and that the energy transfer between the carbon quantum dots and the rare earth ions has a synergistic effect on the efficiency enhancement of the photovoltaic cell. Meanwhile, the TiO2 shell layer also enables the prepared materials to have better properties of self-cleaning and degradation of organic pollutants, which will further improve the visible light utilization of PV cells. NaYF4:Yb3+/Er3+/Tm3+@TiO2-CQDs provides new ideas for the practical application of PV cell efficiency enhancement and the design of new materials.

Mechanical Alloying and Concentration Quenching of the Luminescence of Pr3+ Ions in Chalcogenide Glass

The disadvantage of chalcogenide glasses containing rare earth ions as luminescent materials for the IR optical range is the strong concentration quenching of luminescence due to the non-uniform distribution of rare earth ions in the glass matrix. This study investigates the effect of grinding chalcogenide glass containing Pr3+ ions in a planetary ball mill on its luminescent properties in the near-IR range, as well as its optical properties and structure. The results indicate that milling, under certain conditions, leads to a decrease in the concentration quenching of the luminescence of Pr3+ ions. This finding suggests that milling can be used in the development of glassy materials with the increased efficiency of luminescence of rare earth ions. However, it is essential to consider that high-energy milling may result in the formation of areas with increased pressure in the obtained material, leading to structural changes in the glass.

Luminescent lanthanide hydrogen-bonded organic frameworks for rapid detection of benzophenone-3

2-hydroxy-4-methoxybenzophenone (BP-3) is a common ingredient in sunscreens that can protect human hair and skin from ultraviolet rays. However, it is poisonous to a number of marine organisms, such as algae and corals. Herein, we constructed a new hydrogen-bonded organic framework (HOF) by assembling melamine with pyridine 2,6-dicarboxylic acid (MA-DPA). Subsequently, lanthanide HOF (Ln@MA-DPA) was obtained by anchoring lanthanide ions to the HOF via the coordination of surface carboxylic acid and nitrogen atom. Significantly, Tb@MA-DPA exhibits exceptional luminescent sensing behavior towards BP-3 in aqueous condition, with a limit of detection (LOD) as low as 0.72 μM, and possesses the advantages of high selectivity, fast response and recyclability. We believe that the reported sensor will undoubtedly expand the application scope of HOFs and offers a novel avenue for utilizing HOFs in marine pollution monitoring.

Pt(II)‐Phenanthroline‐Ln(III)‐DOTA d–f Hybrids as Small‐Molecule Theranostics

Abstract1,10‐Phenanthroline d‐ or f‐metal complexes can be utilised in biomedical applications such as imaging or therapeutics. Herein, we designed bimetallic d‐block metal‐phenanthroline f‐block metal‐1,4,7,10‐tetraazacyclododecane‐1,4,7,1,0‐tetraacetic acid (DOTA) conjugates as theranostic agents to simultaneously achieve both of these applications. Luminescence studies show the 1,10‐phenanthroline‐Eu(III)‐DOTA complexes displayed an off/on/off pH‐dependent switch, demonstrating their potential as pH‐responsive lanthanide luminescence probes. Relaxometry studies showed that the 1,10‐phenanthroline‐Gd(III)‐DOTA complexes present a r1 of 5.15±0.05 mM−1 s−1 and could thus be used as magnetic resonance (MR) contrast agents. Complexation of Pt(II) by the 1,10‐phenanthroline moiety resulted in quenching of the Eu(III) luminescence, but an enhancement of the Gd(III) relaxivity (r1=7.53±0.69 mM−1 s−1). Cell viability studies of the d–f hybrids in a cancer cell line showed the potential of these complexes as anticancer agents, as the IC50 for the Pt(II)/Gd(III) complex (IC50=24.9 μM) was lower than that of cisplatin (IC50=31.6 μM). As such, Pt(II)‐1,10‐phenanthroline‐Gd(III)‐DOTA complexes are promising theranostic agents for cancer therapy.

Terbium Phenanthroline Complex as a Luminescent Probe for the Detection of Anthrax Biomarker: Dipicolinic acid.

Dipicolinic acid (DPA) is a prominent biomarker for Anthrax disease. Bacillus anthracis bacterial endospores is composed of DPA as the significant component, which on over inhalation can cause severe health issues. Such contagious and life-threatening pathogens can be employed as bioweapons or biothreat agents for spreading bioterrorism which is a major risk for national security and public health concerns. Hence, effective detection or a surveillance system is essential for preventing the growth of bioterrorism events. Herein, we have developed a Terbium - 1,10 Phenanthroline (Tb-Phen) based lanthanide luminescence complex with bright green fluorescence. On addition of DPA, the green fluorescence is turn-off at a linear range from 0.6 to 4.762 mM. In this effect, 5D4- 7F5 transition caused by 1,10-phenanthroline to Tb3+ at 544nm is restricted due to energy transfer quenching and Inner Filter Effect (IFE). The developed probe shows good sensitivity towards the detection of DPA with other coexisting biomolecules and ions with a low Limit of Detection (LOD) of 5.029 µM. The practical feasibility was evaluated in paper strip assay and extended in real samples such as human serum and tap water with satisfactory recovery percentage. Thereby, probe finds promising application in sensing of anthrax spore biomarker (DPA) and biothreat agents.

Highly Efficient and Thermally Durable Luminescence of 1D Eu3+ Coordination Polymers with Arsenic Bridging Ligands.

In this work, bisarsine oxides were evaluated as novel bridging ligands, aiming to develop practical and efficient luminescent lanthanide coordination polymers. We have synthesized one-dimensional (1D) Eu3+ coordination polymers that incorporate bisarsine oxide bridging ligands and hexafluoroacetylacetonate anions. These polymers exhibited a denser packing of chains compared to analogous polymers bridged with bisphosphine oxides. The coordination polymers demonstrated exceptional thermal stability and substantial emission quantum yields. Additionally, the bisarsine oxides induced a pronounced polarization effect, facilitating a sensitive electric dipole transition that yields considerably narrow band red emission. Remarkably, the Eu3+ coordination polymers with bisarsine oxides maintained intense emission even at 550 K. A distinctive feature of these polymers is their heating-induced emission enhancement observed when the temperature was increased from 300 K to 400 K.

Novel CeF3:Tm3+, Er3+ nanoparticles: NIR up-down conversion luminescence properties based on energy transfer of Tm3+ and Ce3+

A novel CeF3:Tm3+, Er3+ NIR up-down conversion luminescent nanoparticles with highly efficient visible and near-infrared second window (NIR-II) emission were synthesized by direct precipitation and hydrothermal methods. The two different emission modes of visible-NIR II light of Er3+were realized through the energy transfer of Tm3+ and Ce3+at the excitation wavelength of 808 nm. Which successfully combined the narrow emission peaks of visible light and the deep tissue penetration advantage of NIR-II. First, the effects of preparation conditions on the structure, morphology, stability and luminescence properties of CeF3:Tm3+, Er3+ nanoparticles were analyzed by XRD, SEM, TEM and PL. The results showed that the crystallinity, morphology and luminescence intensity of CeF3:Tm3+,Er3+ nanoparticles produced by hydrothermal method (reaction time of 10 h) were optimal compared with that of direct precipitation method. CeF3: Tm3+,Er3+ nanoparticles has better thermal stability, and fluorescence lifetime of 5D0→7F2 (525 nm), 4I15/2→4I11/2 (1066 nm) and 4I15/2→4I13/2 (1386 nm) for Er3+ are 15.51 ns, 48.78 us and 57.06 us, separately. At the same time, the surface of CeF3:Tm3+, Er3+ nanoparticles was modified by PEG and Lys. And then the effects of the surface modification on the hydration size, zeta potential and up-down conversion luminescent properties (visible and NIR-II light emission) were investigated. The results show that the modification of PEG effectively slows down the agglomeration of CeF3:Tm3+, Er3+ nanoparticles and improves their stability and dispersion under the same conditions. More importantly, the modification of PEG effectively increases the up-conversion luminescence intensity of CeF3:Tm3+, Er3+ nanoparticles under 808 nm excitation. Moreover, the CeF3:Tm3+, Er3+-PEG nanoparticles with 20–40 nm showed stronger NIR up-down conversion emission intensity in aqueous solutions (pH = 5,6,7) and better thermal stability. Furthermore, the CeF3:Tm3+, Er3+-PEG nanoparticles has low cytotoxicity and good biocompatibility. This study provides a theoretical basis for the development of high-performance rare-earth NIR up-down conversion luminescence materials.

Functional Construction of a Novel Lanthanide MOF for Efficient Ratio Luminescence Detection of Ethanol Vapor

AbstractIt is necessary to develop excellent sensors for volatile organic compounds (VOCs) detection from the perspective of environmental protection and human health. Luminescent lanthanide metal‐organic frameworks (MOFs) have many advantages such as porosity, luminescence, and structural controllability, making them very suitable as luminescent sensing materials. Based on a functional oriented strategy, novel Ln‐MOFs are successfully constructed and their structure and properties are characterized in detail. A series of vapor luminescence sensing tests have shown that Eu/Tb doped L1‐Eu0.1/Tb0.9 not only exhibits high selectivity for alcohols, especially ethanol vapor, but also has high sensitivity and extremely low detection limit (9.76 mg L−1). To the knowledge, there are no reports on ratio luminescence sensors based on Ln‐MOFs for ethanol vapor, especially those with such excellent performance. Crystal structure determination demonstrates that ethanol binds to the framework through multiple hydrogen bonding interactions, altering the energy transfer efficiency between Tb3+ and Eu3+ to achieve ratio luminescence detection. In addition, L1‐Eu0.1/Tb0.9 has good repeatability, the prepared thin film sensing material also demonstrates the advantages of portability and processability. This work can provide some experience for the development of VOCs sensing materials with better performance.

Tuning lanthanide luminescence from bipyridine-bis(oxazoline/thiazoline) tetradentate ligands

Organic ligands play a pivotal role in lanthanide luminescence by acting as sensitizers for energy absorption and transfer, a phenomenon known as the fluorescence antenna effect. Herein, we introduce two tetradentate nitrogen ligands renowned for their efficient sensitization of lanthanide luminescence, with their luminous efficacy finely adjustable through subtle modifications to their structure. Through the synthesis of four Eu(III)/Tb(III) mononuclear complexes via the complexation of ligands 6,6′-bis(4,5-dihydrooxazol-2-yl)-2,2′-bipyridine (bpybox, L1) and 6,6′-bis(4,5-dihydrothiazol-2-yl)-2,2′-bipyridine (thio-bpybox, L2) with europium/terbium trifluorosulfonate, structural analysis reveals that the lanthanide ion coordinates with eight nitrogen atoms from two ligands and one oxygen atom from trifluorosulfonate. Among them, two Eu(III) complexes ([Eu(L1)2(SO3CF3)](SO3CF3)2EuL1 and [Eu(L2)2(SO3CF3)](SO3CF3)2EuL2) and one Tb(III) complex ([Tb(L1)2(SO3CF3)](SO3CF3)2 TbL1) exhibit luminosity, displaying characteristic lanthanide metal ion luminescence characterized by high fluorescence quantum yields and prolonged excited state lifetimes. In contrast, TbL2 ([Tb(L2)2(SO3CF3)](SO3CF3)2) is non-luminous, with the sole structural distinction being the substitution of oxygen atoms with sulfur atoms within the ligand. This minor alteration significantly impacts the triplet (3T) state energy level of the ligands, thereby influencing their sensitizing effect on Tb(III) luminescence. These findings underscore the remarkable efficiency of bpybox-type ligands as sensitizers for Ln(III) luminescence, with their structural versatility enabling effective modulation of luminous capacities and efficiency.

Thermally stable Tb3+/Sm3+-doped Lu2O2S phosphors with tunable multicolor luminescence under light and X-ray excitation

Lu2O2S has high density, high melting temperature, and favorable thermal stability, making it an excellent matrix material for rare earth luminescence and X-ray sensitization screens. However, achieving high quality fluorescent powders with high crystal quality on a large scale is still challenging. By employing an optimized solid phase approach, Lu2O2S:Tb3+/Sm3+phosphors with a hexagonal shape and uniform particle size and showing high crystallization have been successfully synthesized. Spectral analysis reveals energy interaction between Sm3+ and Tb3+ in the Lu2O2S system (multistage interaction), indicated by spectral overlap, relative changes in luminescence intensity, and lifetime decay. By changing the excitation wavelength and dopant concentration, multicolor phosphors such as yellow-–green, orange–red, and orange–yellow could be created. Temperature-dependent emission spectroscopy shows that the system shows good luminescence performance even at high temperatures. X-ray excitation spectroscopy further confirm that the phosphors emit different colors (yellow, green and red) depending on the doping concentrations of Tb3+ and Sm3+ ion, indicating that the system has wide application potential in color displays and other relevant fields.

A fluorescent terbium-metal-organic framework material for high-sensitivity detection of vomitoxin and oxytetracycline hydrochloride in water.

A unique luminescent lanthanide metal-organic framework (LnMOF)-based fluorescence detection platform was utilized to achieve sensitive detection of vomitoxin (VT) and oxytetracycline hydrochloride (OTC-HCL) without the use of antibodies or biomolecular modifications. The sensor had a fluorescence quenching constant of 9.74 × 106 M-1 and a low detection limit of 0.68 nM for vomitoxin. Notably, this is the first example of a Tb-MOF sensor for fluorescence detection of vomitoxin. We further investigated its response to two mycotoxins, aflatoxin B1 and ochratoxin A, and found that their Stern-Volmer fluorescence quenching constants were lower than those of VT. In addition, the fluorescence sensor realized sensitive detection of OTC-HCL with a detection limit of 0.039 μM. In conclusion, the method has great potential as a sensitive and simple technique to detect VT and OTC-HCL in water.

Luminescence of Lanthanide Complexes in Mesoporous Silica Matrices: A Textbook Example of Tris‐Dipicolinate Europium Complex Adsorbed in SBA‐15

AbstractThe incorporation of luminescent lanthanide complexes in inorganic matrices opens appealing possibilities in the rational upstream conception of new luminescent materials with easier recyclability. In this regard, the influence of SBA‐15 mesoporous silica, as a host matrix, on the photophysical properties of europium‐trisdipicolinate cesium salt is investigated. The lanthanide complex can be completely and reversibly adsorbed on the silica, using incipient wetness impregnation (IWI) in WATER, without the need of anchoring groups or covalent bonding on the silica surface. This specific procedure allows the homogeneous dispersion of the lanthanide complex into the host silica matrix. Appropriately assessing the photophysical properties of the targeted luminescent material proved remarkably challenging, demanding utmost caution, particularly due to the strong scattering of the mesoporous matrices. Additionally, while the observations confirm an important increase of luminescence lifetimes of lanthanide complexes upon integration into these mediums, this variation is attributed to the differing refractive indexes and not to specific surface interactions or confinement effect. Indeed, it appeared that previous literature precedents depicted erroneous exhalations of the complexes intrinsic quantum yield due to the repeated use of erroneous refractive index values. In the meantime, the luminance of these materials under UV irradiation improves drastically in comparison to what is obtained with the physical dispersion of micro‐crystals of the lanthanide complex onto silica. It is demonstrated that this improvement is due to a reduced inner filter effect in the adsorbed samples. In this regard, IWI of lanthanide complexes in the mesoporous matrices method could be of interest in the development of recyclable emitting layers, less demanding in terms of emitter quantity.

Ultra-Broadband Plasmon Resonance in Gold Nanoparticles Precipitated in ZnO-Al2O3-SiO2 Glass

Optical materials with a tunable localized surface plasmon resonance (LSPR) are of great interest for applications in photonics and optoelectronics. In the present study, we explored the potential of generating an LSPR band with an ultra-broad range of over 1000 nm in gold nanoparticles (NPs), precipitated through a thermal treatment in ZnO-Al2O3-SiO2 glass. Using optical absorption spectroscopy, we demonstrated that the LSPR band’s position and shape can be finely controlled by varying the thermal treatment route. Comprehensive methods including Raman spectroscopy, X-ray diffraction, and high-resolution transmission electron microscopy were used to study the glass structure, while computational approaches were used for the theoretical description of the absorption spectra. The obtained results allowed us to suggest a scenario responsible for an abnormal LSPR band broadening that includes a possible interparticle plasmonic coupling effect taking place during the liquid–liquid phase separation of the heat-treated glass. The formation of gold NPs with an ultra-broad LSPR band in glasses holds promise for sensitizing rare earth ion luminescence for new photonics devices.

Synthesis of near-infrared-activated YF3:Yb3+, Tm3+/Bi2MoO6 upconversion photocatalytic materials for the photocatalytic degradation of antibiotics based on fluorescence resonance energy transfer

Photocatalytic degradation of pollutants, an ecofriendly technology, is widely used for environmental remediation. However, the design and synthesis of photocatalytic materials for near-infrared light photocatalysis are challenging. In this study, an upconversion photocatalyst with fluorescence resonance energy transfer (FRET), YF3:Yb3+, Tm3+/Bi2MoO6 (YFYT/BMO), was developed and synthesised based on rare-earth upconversion luminescence. YFYT converted near-infrared (NIR) light into blue–violet light via upconversion. The rapid decay of the fluorescence lifetime of YFYT/BMO at 478 nm (Tm3+:1G4-3H6) verified that FRET efficiently occurred between YFYT and BMO. The degradation rate of tetracycline by YFYT/BMO was 2.6 times higher than that by BMO under NIR light. A great enhancement of 42.1 % on the tetracycline degradation efficiency was achieved in YFYT/BMO compared with pure BMO within 90 min of visible-NIR irradiation. This study provides a basis for developing and designing rare-earth upconversion photocatalytic materials that can achieve excellent photocatalytic degradation of antibiotics using NIR light for environmental remediation.

A 20-Metal Zn(II)-Cd(II)-Eu(III) Nanocluster with Qualitative and Quantitative Luminescence Detection of Meloxicam (an Anti-Inflammatory Drug).

Meloxicam (MLX) is a novel nonsteroidal anti-inflammatory drug, but on the other hand, it has become one of the common microcontaminants in surface waters and sewage. Herein, we report the preparation of a ternary-metal Zn(II)-Cd(II)-Eu(III) nanocluster 1 for the response of MLX through the enhancement of lanthanide luminescence. The luminescence sensing behavior of 1 is expressed by the equation I615nm = 3060 × [MLX] + 46,604, which can be used in the quantitative analysis of MLX concentrations in meloxicam dispersible tablets. Filter paper strips bearing 1 can be used to qualitatively detect MLX by a color change to red under a UV lamp. The luminescence response time is no more than five s, and the detection limit is as low as 2.31 × 10-2 nM.

Frequency converting and digital modulation of light derived from lanthanide for signal encoding and logic computing

AbstractModulation of light underpins a central part of modern optoelectronics. Conventional optical modulators based on refractive‐index and absorption variation in the presence of an electric field serve as the workhorse for diverse photonic technologies. However, these approaches based on electro‐refraction or electro‐absorption effect impose limitations on frequency converting and signal amplification. Lanthanide‐activated phosphors offer a promising platform for nonlinear frequency conversion with an abundant spectrum. Here, we propose a novel approach to achieve frequency conversion and digital modulation of light signal by coupling lanthanide luminescence with an electrically responsive ferroelectric host. The technological benefits of such paradigm‐shifting solution are highlighted by demonstrating a quasi‐continuous and enhancement of the lanthanide luminescence. The ability to locally manipulate light emission can convert digital information signals into visible waveforms, and visualize electrical logic and arithmetic operations. The proof‐of‐concept device exhibits perspectives for developing light‐compatible logic functions. These results pave the way to design more controllable lanthanide photonics with desired opto‐electronic coupling.image

Comparing thermoluminescence data on lanthanides in 36 compounds with predictions from vacuum referred binding energy diagrams

Thermoluminescence (TL) often involves the liberation of a charge carrier (an electron or a hole) from a charge carrier trapping centre into the conduction band (CB) or the valence band (VB) with subsequent recombination with a counter charge carrier at a luminescence centre. TL glow peak analysis can provide the energy ΔEt needed to liberate such charge carrier which then defines the location of the charge transition levels (CTL) of the carrier trapping centres below the CB-bottom or above the VB-top. The temperature at the maximum of the TL glow peak changes 3–4 K per 0.01 eV change in ΔEt thus providing an extremely sensitive probe of energy changes in CTLs. This work collects and reviews data on glow peaks due to electron or hole release from lanthanide dopants in 36 different inorganic compounds. To compare results from different literature sources, data were always re-analysed using the same method that is solely based on the temperature at the maximum of the glow peak. The changes in ΔEt along the lanthanides series provides insight at the sub 0.1 eV level on the changes in CTL energies. We will use a compound-dependent parameter to account for the nephelauxetic effect and a compound dependent parameter to account for lattice relaxation around the lanthanide. Together with information from lanthanide luminescence spectroscopy, the vacuum referred binding energy (VRBE) diagram will be constructed for each compound. The lanthanide electron or hole trap depth read from the VRBE scheme will be compared with that derived from the TL glow peak. Surprisingly good agreement will be demonstrated.

Preparation of chalcogenide perovskite SrHfS3 and luminescent SrHfS3:Eu2+ thin films

As an emerging family of perovskites with S or Se anions, chalcogenide perovskites possess excellent optoelectronic properties that are comparable with halide perovskites, e.g., efficient carrier transport abilities and defect tolerance. Moreover, they are thermodynamically stable and constituted by eco-friendly elements. Among them, chalcogenide perovskite SrHfS3 is found to be a promising light emitting material and is experimentally demonstrated to be a suitable host for the luminescent lanthanide ions like Eu2+. In order to be applied in practical light emitting devices, preparation of the thin film is a critical step. Unfortunately, there are few reports on the growth of SrHfS3 thin films, hindering the knowledge of their thin film properties and applications. In this work, SrHfS3 thin films are prepared by magnetron sputtering from a commercial SrHfO3 target and subsequent sulfurization. Then, Eu2+ doping in SrHfS3 thin films is achieved by co-sputtering from a home-made EuS target. The SrHfS3 thin films exhibit high-quality crystallinity, smooth morphology, and high p-type mobility. With efficient Eu2+ doping strategy, SrHfS3:Eu2+ thin films show intensive red light, which sets foundations for their further application in practical light emitting devices.

Dual Optical Response Strategy for the Detection of Cytochrome c Using Highly Luminescent Lanthanide-Based Nanotubular Sensor Arrays.

Here, we demonstrate a label-free dual optical response strategy for the detection of cytochrome c (Cyt c) with ultrahigh sensitivity using highly luminescent lanthanides containing inorganic-organic hybrid nanotubular sensor arrays. These sensor arrays are formed by the sequential incorporation of the photosensitizers 2,3-dihydroxynaphthalene (DHN) or 1,10-phenanthroline (Phen), and trivalent lanthanide terbium ions (Tb3+) into sodium lithocholate (NaLC) nanotube templates. Our sensing platform relies on the detection and quantification of Cyt c in solution by providing dual photoluminescence quenching responses from the nanotubular hybrid arrays in the presence of Cyt c. The large quenching of the sensitized Tb3+ emission within the DHN/Phen-Tb3+-NaLC nanotubular sensor arrays caused by the strong binding of the photosensitizers to Cyt c provides an important signal response for the selective detection of Cyt c. This long-lived lanthanide emission response-based sensing strategy can be highly advantageous for the detection of Cyt c in a cellular environment eliminating background fluorescence and scattering signals through time-gated measurements. The DHN containing nanotubular sensor arrays (DHN-NaLC and DHN-Tb3+-NaLC) provide an additional quenching response characterized by a unique spectral valley splitting with quantized quenching dip on the DHN fluorescence emission. This spectral quenching dip resulting from efficient FRET between the protein bound DHN photosensitizer and the heme group of Cyt c serves as an important means for specific detection and quantification of Cyt c in the concentration range of 0-30 μM with a low detection limit of around 20 nM.