Trioctylphosphine Oxide Research Articles

An Innovative Anode Interface Combination for Perovskite Solar Cells with Improved Efficiency, Stability, and Reproducibility

Rational design and engineering of top interface layers with combined properties of effective passivation, high thermal‐ and photo‐stability are effective methods to advance the commercialization of perovskite photovoltaics. Here, an innovative anode interface combination is developed based on alcohol‐dispersed poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) nanoparticles as the hole transport material and chlorobenzene‐dissolved trioctylphosphine oxide (TOPO) as the passivation agent. It is shown that instead of the commonly used 2D passivation ligands, TOPO‐passivated perovskite films exhibit greatly improved thermal stability. Furthermore, the passivation contributes to an enhanced carrier lifetime and reduced surface trap density, yielding an improvement in the quasi‐fermi‐level splitting of 57 meV. To maintain surface passivation during solution processing of further layers, it is necessary to develop a hole transport layer that can be processed from orthogonal solvents. P3HT nanoparticles formulated in alcoholic media fully meet this requirement, clearly benefitting from their high vertical conductivity and extremely low contact resistance with carbon electrodes. Based on this configuration, device efficiency of up to 18.4% is demonstrated for perovskite solar cells with fully solution‐processed carbon electrodes, along with significantly improved device stability and reproducibility.

Perspectives of Using DES-Based Systems for Solid–Liquid and Liquid–Liquid Extraction of Metals from E-Waste

In recent years, the linear economic model and global warming have shown that it is necessary to move toward a circular economic model. In this scenario, the recycling of waste electrical and electronic equipment (WEEE) with green processes is one of the pending tasks; thus, in the present review, advances in the solid–liquid and liquid–liquid extraction processes, processes among the most important for the recovery of metals from ores or WEEE, with green solvents such as deep eutectic solvents (DES) are presented and analyzed, identifying the present and future challenges. To date, most articles focused on one of the processes, be it solid–liquid or liquid–liquid extraction, while few reports included the entire hydrometallurgical process, which could be due to heterogeneity of the WEEE, a characteristic that influences determining the leaching kinetic and the leaching mechanisms. A deeper understanding of the phenomenon would help improve this process and the next stage of liquid–liquid extraction. This also leads to the fact that, at the liquid–liquid extraction stage, most articles considered synthetic pregnant leach solutions to evaluate each of the variables, whereas the stripping of the ions and the recycling of the DESs in continuous processes is a challenge that should be addressed in future work. From the analysis, for WEEE leaching, it was identified that acid DESs are those achieving the best extraction percentages in the leaching of copper, lithium, and cobalt, among others, where the most studied hydrogen bond acceptor (HBA) is choline chloride with an acid (e.g., citric or lactic acid) as the hydrogen bond donor (HBD). For the liquid–liquid extraction of ions is a greater variety of HBAs (e.g., lidocaine, trioctylphosphine oxide and triphenyl phosphate) and HBDs (e.g., decanoic acid, thenoyltrifluoroacetone, and benzoyltrifluoroacetone) used; however, studies on the extraction of cobalt, lithium, copper, and nickel stand out, where the pH and temperature parameters have great influence.

A New Extraction System Based on Isopropyl Salicylate and Trioctylphosphine Oxide for Separating Alkali Metals.

It was established that isopropyl salicylate can be used similarly to 1,3-diketones as a key component for a new efficient extraction system for selective separation of alkali metal cations. According to DFT modeling of complexes of isopropyl salicylate and 1,3-diketone with alkali metal cations (Li+, Na+, K+), six-membered metallacycles are formed whose stability decreases along the series Li > Na > K, which results in the observed enhanced affinity to lithium. The extraction ability of isopropyl salicylate is manifested in the presence of trioctylphosphine oxide (TOPO). The newly obtained complexes of isopropyl salicylate with alkali metal cations as well as their extracts in a mixture with TOPO are characterized by means of FT-IR, Raman, and NMR spectroscopy. The probable structure of the extracted lithium complex is presumed and the role of TOPO in the extraction process is investigated in detail. Extraction experiments showed extremely high separation coefficients for Li/Na and Li/K pairs in the extraction from a model multi-component solution.

Synthesis of a New Chelating Iminophosphorane Derivative (Phosphazene) for U(VI) Recovery.

A new synthetic chelating N–hydroxy–N–trioctyl iminophosphorane (HTIP) was prepared through the reaction of trioctylphosphine oxide (TOPO) with N–hydroxylamine hydrochloride in the presence of a Lewis acid (AlCl3). Specifications for the HTIP chelating ligand were successfully determined using many analytical techniques, 13C–NMR, 1H–NMR, FTIR, EDX, and GC–MS analyses, which assured a reasonable synthesis of the HTIP ligand. The ability of HTIP to retain U(VI) ions was investigated. The optimum experimental factors, pH value, experimental time, initial U(VI) ion concentration, HTIP dosage, ambient temperature, and eluents, were attained with solvent extraction techniques. The utmost retention capacity of HTIP/CHCl3 was 247.5 mg/g; it was achieved at pH = 3.0, 25 °C, with 30 min of shaking and 0.99 × 10−3 mol/L. From the stoichiometric calculations, approximately 1.5 hydrogen atoms are released during the extraction at pH 3.0, and 4.0 moles of HTIP ligand were responsible for chelation of one mole of uranyl ions. According to kinetic studies, the pseudo–first order model accurately predicted the kinetics of U(VI) extraction by HTIP ligand with a retention power of 245.47 mg/g. The thermodynamic parameters ΔS°, ΔH°, and ΔG° were also calculated; the extraction process was predicted as an exothermic, spontaneous, and advantageous extraction at low temperatures. As the temperature increased, the value of ∆G° increased. The elution of uranium ions from the loaded HTIP/CHCl3 was achieved using 2.0 mol of H2SO4 with a 99.0% efficiency rate. Finally, the extended variables were used to obtain a uranium concentrate (Na2U2O7, Y.C) with a uranium grade of 69.93% and purity of 93.24%.

Removal of of toxic metal ions (Ni2+ and Cd2+) from wastewater by using TOPO decorated iron oxide nanoparticles

In real engineering applications, nanoparticles can face hurdles of complex behavior of pollutants, for which electrostatic forces and background electrolyte can prove to be one of the robust mechanisms to remove pollutants from wastewater. In the present work, magnetite (Fe3O4) nanoparticles (NPs) and trioctyl phosphine oxide (TOPO) coated Fe3O4 NPs were synthesized and characterized for removing divalent Ni2+ and Cd2+ ions. Morphological and chemical analysis of both NPs was performed, and batch adsorption experiments were performed to study the influence of different pH ranges, concentrations of adsorbents and different contact timings. TOPO functionalized magnetite nanoparticles were found to have better adsorption capacities as compared to Fe3O4 at higher pH values. Isotherm models were run to identify the adsorption process. Langmuir isotherm model data fitted best for both metal ions adsorption, while Freundlich data suited best only for Ni2+ ions. The regression values for kinetic models confirmed that pseudo-second-order fitted best to the adsorption of both Ni2+ and Cd2+. Higher adsorption values were noticed for Ni2+ at higher dosages of both bare and TOPO-coated iron oxide NPs. Cadmium was found to have no influence of adsorbent dosage. Contact time was found to impact sorption values, i.e., adsorption was greater initially and then decreased with the passage of time. The study concludes that TOPO decorated Fe3O4 NPs can be more efficiently used for wastewater treatment. Furthermore, the presence of alkyl chains in TOPO can be immobilized at surface of metals to undergo adsorption more efficiently.

Mextral® 6103H/naphthenic acid/TOPO synergistic extraction system for recovery of nickel and cobalt from nickel laterite

Combination of the α-hydroxyoxime and the carboxylic acids results in synergistic extraction of nickel and cobalt and exhibits excellent performance of separating nickel and cobalt from manganese, magnesium and calcium, but they have the drawbacks of slow nickel stripping kinetics. In this study, trioctylphosphine oxide (TOPO), as an accelerator, was used to improve the nickel stripping kinetics of the Mextral 6103H/naphthenic acid system. The results showed that the addition of 0.35 M TOPO to 0.35 M Mextral 6103H/0.5 M naphthenic acid system significantly improved the nickel stripping kinetics. After mixing for 3 min, 96% stripping efficiency was obtained with 15 g/L H2SO4 at an O/A ratio of 1:1 and 25 ℃. The extraction pH isotherms revealed that more than 99.0% copper, 99% cobalt, 97% nickel and 86% zinc were extracted at pH 5.5, and only 6% manganese, 0.08% magnesium and 0.24% calcium were co-extracted. At pH 5.0, 87% calcium, 96% manganese and 97% magnesium can be scrubbed, resulting in 5.3 mg/L manganese and less than 0.5 mg/L magnesium and calcium remained in the scrubbed organic solution. Full stripping of nickel and cobalt could be achieved in two stages with 50 g/L nickel and 150 g/L H2SO4 at an O/A ratio of 10:1 and 25 ℃. Thus, compared with TBP, TOPO was more efficient for improving the nickel stripping kinetics at room temperature, which can reduce the power consumption and lead to clear production.

Extraction of Th(IV) metal ions with trioctylphosphine oxide dissolved in kerosene using multi-dropped liquid membrane technique

In the present work, the experimental investigation and modeling of Th(IV) metal ions recovery have been carried out by using the recycling mode of the multi-dropped liquid membrane (MDLM) technique. Experiments were done at operational conditions: studies of the MDLM system with single and double reactor column (continuous system). The optimum condition for the extraction of Th(IV) was a 0.50 M HNO3 solution as donor phase, 0.10 molL-1 TOPO as a carrier, and 0.10 M H2SO4 as acceptor phase. The transport percentage of Th(IV) was increased up to >98% and the calculated activation energy which is 6.52 kcalmol-1 indicated that the process was diffusion controlled by Th(IV) ions. The reuptake efficiencies of the extraction of Th(IV) ions in the presence of Cd(II), Cu(II), Ni(II), and Pb(II) separately under optimized experimental conditions were investigated. Therefore, the MDLM system might be useful for the design and the optimization of the recovery of Th(IV) in the recycling mode.

Evaluation of Zeolite Acidity by 31P MAS NMR Spectroscopy of Adsorbed Phosphine Oxides: Quantitative or Not?

31P magic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy of adsorbed alkyl-substituted phosphine oxides has witnessed tremendous progress during the last years and has become one of the most informative and sensitive methods of zeolite acidity investigation. However, quantitative evaluation of the number of sites is still a challenge. This study clarifies the main origin of errors occurring during NMR experiments, introduces the appropriate standards (both internal and external), and determines the relaxation parameters and the conditions for the acquisition and integration of spectra. As a result, a methodology for the quantitative measurement of the content of Brønsted and Lewis sites and the amount of internal and external silanol groups is established. The application of probe molecules of different sizes (namely, trimethylphosphine oxide (TMPO), tri-n-butylphosphine oxide (TBPO), and tri-n-octylphosphine oxide (TOPO)) is shown to be a good tool for distinguishing between the active sites inside the zeolite pores, mesopores, and on the outer crystal surface. The methodology proposed is verified on BEA zeolites different in composition, texture, and morphology.

Light quenching of photoluminescence in hybrid films of InP/InAsP/InP nanowires and CdSe/ZnS colloidal quantum dots

We investigate the photoluminescence of a film obtained by the uniform deposition of a colloidal solution of CdSe/ZnS quantum dots capped by trioctylphosphine oxide on an array of isolated InP/InAsP/InP nanowires and subsequently removed from the substrate. The photoluminescence spectrum of the film shows emission bands corresponding to InAsP nano-insertions (1.25–1.5 μm) and quantum wells (1.0–1.2 μm). We find that the dependence of the photoluminescence intensity on the excitation intensity has a nonlinear character, which we interpret as a manifestation of the light quenching effect, and that the photodynamics of excitation of the nano-insertions and quantum wells differ from each other. We analyse the light quenching effect taking into account the significant increase in the luminescence intensity observed in such hybrid film as compared to an array of isolated InP/InAsP/InP nanowires. We hypothesize the possible suppression of Auger relaxation due to multistep nonradiative transfer of excitation.

Investigation of green solvents for the extraction of phenol and natural alkaloids: Solvent and extractant selection

Green solvents have been gaining momentum to replace traditional volatile organic compounds (VOCs) in solvent extraction processes due to environmental and health concerns. In this work, phenol was used as a model compound for natural alkaloid extraction to find an appropriate alternative among green bio-derived solvents, including d-limonene, α-pinene, p-cymene, 2,5-dimethylfuran (DMF) and CyreneTM. Moreover, extractants including Cyanex 923®, trioctylphosphine oxide (TOPO), tri-butyl-phosphate (TBP) and Alamine 336 were evaluated to investigate the improvement to phenol extraction performance. The selection of extractants and green solvents is based on an evaluation matrix composing several criteria including toxicity, biodegradability, feedstock, market price, physicochemical properties and extraction performance. Hansen solubility parameters (HSPs) and conductor-like screening model (COSMO-SAC) with direction character of hydrogen bonding parameters (DHB) were used to assist the selection process. The COSMO predictions are in good agreement with the experimental data and within 20% deviation in most cases. Finally, d-limonene and Cyanex 923® were selected as the solvent replacement and extractant, respectively. 0.2 M and 0.6 M Cyanex 923® in d-limonene and xylene were further investigated via phenol and morphine isotherms at optimised pH values. It was found that d-limonene exhibits acceptable extraction performance for phenol extraction but is less efficient for morphine extraction as compared to xylene possibly due to emulsion formation during alkaloid extraction.

Nonsolvent-induced phase separation preparation of porous TOPO-mixed polyethersulfone membranes for selective clearance of p-cresol from simulated serum

Uremic toxin p-cresol will accumulate in the blood when the kidney function declines, causing an increased risk of cardiovascular diseases and the mortality of the patient with end-stage rental disease. The incomplete removal of p-cresol even by a high-flux hemodialysis is mainly because most of p-cresol is bound to albumin. The efficient removal of such a toxin by a promising way is highly desired. In this study, porous polyethersulfone (PES) membranes were prepared by nonsolvent-induced phase separation, to which an additive polyvinylpyrrolidone (PVP) and a solvating extractant tri-n-octylphosphine oxide (TOPO) were added. These membranes were applied to selectively remove p-cresol from simulated serum containing comparatively large amounts of other small toxins like urea and creatinine. Morphological and physicochemical properties of the prepared TOPO-mixed membranes were examined. The adsorption isotherms of p-cresol measured at 37 °C and pH 7.4 on the prepared membranes were better described by the Langmuir equation, in contrast to the Freundlich equation. Under the ranges studied, a maximum adsorption capacity of 1.77 mmol/g for p-cresol was obtained. Cross-flow adsorption of a mixture of urea, creatinine, and p-cresol (initially, 2300, 150, and 50 mg/L, respectively) in a total reflux mode revealed that 46% of p-cresol, 1.0% of urea, and 1.1% of creatinine were removed after 4 h of operation (membrane area 42 cm2, flow rate 0.2 L/min, and volume 0.5 L). This highlighted the high selectivity of p-cresol clearance over two other toxins using the prepared TOPO-mixed membranes. The hemolysis tests and time-course measurements of the cellular viability of fibroblast NIH/3T3 and leukemic THP1 cells demonstrated that the prepared TOPO-mixed membranes were hemo- and bio-compatible; therefore, they were promising and potential for future applications.

Mechanistic Insight into the Precursor Chemistry of ZrO2 and HfO2 Nanocrystals; towards Size-Tunable Syntheses.

One can nowadays readily generate monodisperse colloidal nanocrystals, but a retrosynthetic analysis is still not possible since the underlying chemistry is often poorly understood. Here, we provide insight into the reaction mechanism of colloidal zirconia and hafnia nanocrystals synthesized from metal chloride and metal isopropoxide. We identify the active precursor species in the reaction mixture through a combination of nuclear magnetic resonance spectroscopy (NMR), density functional theory (DFT) calculations, and pair distribution function (PDF) analysis. We gain insight into the interaction of the surfactant, tri-n-octylphosphine oxide (TOPO), and the different precursors. Interestingly, we identify a peculiar X-type ligand redistribution mechanism that can be steered by the relative amount of Lewis base (L-type). We further monitor how the reaction mixture decomposes using solution NMR and gas chromatography, and we find that ZrCl4 is formed as a by-product of the reaction, limiting the reaction yield. The reaction proceeds via two competing mechanisms: E1 elimination (dominating) and SN1 substitution (minor). Using this new mechanistic insight, we adapted the synthesis to optimize the yield and gain control over nanocrystal size. These insights will allow the rational design and synthesis of complex oxide nanocrystals.

Solution route processed and organically-Capped Quinary CuIn1-xGax(SySe1-y)2 (CIGSSe) inks for use in low-cost photovoltaics

Multicomponent chalcogenides are a class of derived materials that present a compelling vision that allows for the realization of benefits that are limited in their pristine counterparts. CIGSSe is one such material that constitutes the dual role of prominent chalcogens, i.e., sulfur and selenium. The benefits possessed due to both sulfur and selenium's presence influence the improvement in properties compared to their other counterparts. The dual role offered by both the constituents is noteworthy as one of them, i.e., sulfur, aids in enhancing the material's bandgap. Simultaneously, the other, i.e., selenium, is responsible for eliminating the porosity in thin-films of these chalcogenides. Comparing the properties of individual CIGSe and CIGS with quinary CIGSSe can lead to the discernment of a material with properties particularly desirable for the potential photovoltaic absorber. To the best of the author's knowledge, the quinary CIGSSe nanocrystals' colloidal synthesis employs organic ligands-TOP(tri octyl phosphine)/TOPO (tri octyl phosphine oxide) has been reported for the first time. Technologically, this solution-based synthesis's main benefit is the ease of formation of the colloidal-ink for a scalable film formation on various compatible substrates (rigid/flexible) via the printing route for photovoltaics application.

Greener Surfactant-Assisted Microextraction Method for the Determination of Fluoroquinolones in Chicken Livers by High-Performance Liquid Chromatography

A simple and environmentally friendly surfactant-assisted microextraction method combined with high-performance liquid chromatography fluorescence detection was developed for the determination of six fluoroquinolones in chicken livers. In the method, the analytes were transported into the hydrophobic extraction by ionic and nonionic surfactants. Three different surfactants were studied for this purpose, cationic Methyltrioctyl ammonium chloride (Aliquat 336), anionic sodium dodecyl sulfate (SDS), and nonionic trioctyl phosphine oxide (TOPO). Under optimum conditions, the limits of detection (LODs) and limits of quantification (LOQs) obtained using anionic surfactant ranged from 5 to 23 µg kg-1 and 15 to 78 µg kg-1 respectively. The LODs obtained from using cationic surfactant ranged from 9 to 21 µg kg-1 while the LOQs ranged from 31 to 71 µg kg-1. The LODs obtained from the method using nonionic surfactant ranged from 9 to 20 µg kg-1 and the LOQs ranged from 29 to 67 µg kg-1. Surfactant assisted-dispersive liquid liquid microextraction using SDS and Aliquat 336 were statistically compared and no significant statistical difference was observed between the two methods. The results obtained in this study indicate that the proposed method is cost-effective and environmentally friendly for the extraction and determination of fluoroquinolones in solid biological samples.

Investigation of heated silver nanowires under surface modification

Silver nanowires (Ag NWs) have received much attention and applied in many fields due to their excellent conductivity. Hence, Ag NWs were usually integrated with low conductive materials to enhance the conductivity of the overall system. In some conditions, the surface of Ag NWs need to be modified before combining with other materials. There are many ways to change and prepare the surface of Ag NWs, for example, ligand exchange which is a simple process. TOPO (trioctylphosphine oxide) is a robust coordinating ligand and is classified as an essential component for low-dimensional nanomaterials. In comparison, ODE (1-octadecene) is a noncoordinating ligand that is often used in quantum nanomaterials preparation. In this experiment, we investigated the surface attachment for ligand exchange of TOPO and ODE on the surface of Ag NWs under variations of reaction times at 150°C. The scanning electron microscope showed the rough surface when TOPO was added, and there was no noticeable change of surface when ODE was added. These results are promising for the preparation of heterostructure in the future.

Trioctylphosphine Oxide (TOPO)-Assisted Facile Fabrication of Phosphorus-Incorporated Nanostructured Carbon Nitride Toward Photoelectrochemical Water Splitting with Enhanced Activity.

Designing nanostructured arrays of two-dimensional surfaces and interfaces is a versatile approach to increasing their photoelectrochemical activity. Here, phosphorus (P)-incorporated nanostructured carbon nitride (h-PCN) with an enlarged surface area is fabricated by employing trioctylphosphine oxide (TOPO) as a dopant precursor for visible-light-driven photoelectrochemical water splitting to produce hydrogen. The structural, morphological, and electronic properties of the photocatalyst have been characterized through various physicochemical techniques. We show that the incorporation of P into the g-C3N4 framework enhances light absorption over broad regimes, charge separation, and migration, as well as the specific surface area, showing excellent photocurrent enhancement (5.4 folds) in the cathodic direction as compared to bulk g-C3N4. Moreover, the photocathode shows 3.3-fold enhancement in current at zero biased potential. Without using any cocatalyst, the photoelectrodes produced 27 μmol h-1 of H2 and 13 μmol h-1of O2 with 95% faradic efficiency. The excellent photoelectrochemical behavior toward water-splitting reactions by the photoelectrode is attributed to the synergistic effect of P incorporation and active sites emerging from the nanostructured architecture of the material. This work demonstrates the facile fabrication of nanostructured P-incorporated g-C3N4 toward water-splitting reactions to produce hydrogen without using a cocatalyst in a simple and cost-effective way.

Extraction Behavior of Metal-Thiocyanato Complexes into Third Phase Formed in an Ionic Liquid Extraction System Using Trioctylphosphine Oxide

Extraction Behavior of Metal-Thiocyanato Complexes into Third Phase Formed in an Ionic Liquid Extraction System Using Trioctylphosphine Oxide

Mechanism study on the synergistic effect and emulsification formation of phosphine oxide with β-diketone for lithium extraction from alkaline systems

• More accurate synergistic mechanism of β-diketone and phosphine oxide for lithium extraction was confirmed. • The extraction species of Li(H 2 O)·TTA·TOPO was determined by the synergistic system. • The reasons for the ready emulsification formation was analysed. • Possible measure to solve the emulsification problem was proposed. The synergisms of β-diketone and phosphine oxide are very efficient for lithium selective extraction from alkaline systems, and have been obtained wide applications, especially for lithium recovery from salt lake brines. However, the systems are ready to form emulsification which seriously impacted their practical applications. In this study, the synergistic mechanism of β-diketone and phosphine oxide was intensively studied using a typical β-diketone of HTTA (2-Thenoyltrifluoroacetone) and TOPO (Trioctylphosphine oxide) through extraction parameter relationships, FT-IR measurements, structure computational simulations. It is found that one molar water readily presented in the extracted species forming Li·(H 2 O)·TTA·TOPO, while two molar water presented when HTTA alone was used which more readily forms emulsification or even solid. When TOPO was attended, one molar of water was replaced by it as there is an unconfirmed “boundary“ formed between them which will significantly mitigate the emulsification formation.

Bis(4-methylpiperidine-1-carbodithioato)-lead(II) and Bis(4-benzylpiperidine-1-carbodithioato)-lead(II) as Precursors for Lead Sulphide Nano Photocatalysts for the Degradation of Rhodamine B.

Bis(4-methylpiperidine-1-carbodithioato)-lead(II) and bis(4-benzylpiperidine-1-carbodithioato)-lead(II) were prepared and their molecular structures elucidated using single crystal X-ray crystallography and spectroscopic techniques. The compounds were used as precursors for the preparation of lead sulphide nano photocatalysts for the degradation of rhodamine B. The single crystal structures of the lead(II) dithiocarbamate complexes show mononuclear lead(II) compounds in which each lead(II) ion coordinates two dithiocarbamato anions in a distorted tetrahedral geometry. The compounds were thermolyzed at 180 ℃ in hexadecylamine (HDA), octadecylamine (ODA), and trioctylphosphine oxide (TOPO) to prepare HDA, ODA, and TOPO capped lead sulphide (PbS) nanoparticles. Powder X-ray diffraction (pXRD) patterns of the lead sulphide nanoparticles were indexed to the rock cubic salt crystalline phase of lead sulphide. The lead sulphide nanoparticles were used as photocatalysts for the degradation of rhodamine B with ODA-PbS1 achieving photodegradation efficiency of 45.28% after 360 min. The photostability and reusability studies of the as-prepared PbS nanoparticles were studied in four consecutive cycles, showing that the percentage degradation efficiency decreased slightly by about 0.51–1.93%. The results show that the as-prepared PbS nanoparticles are relatively photostable with a slight loss of photodegradation activities as the reusability cycles progress.

Triplet Exciton Enhanced Radioluminescence of Ga3+/Tb3+ Metallacrown Scintillators for X‐Ray Detection

AbstractThe increasing demand for radiation detection in many applications has led to demanding requirements for scintillators. Realizing low‐dose, pollution‐free, and reliable X‐ray detection has become a key technical challenge. Here, a triplet‐enhanced lanthanide radioluminescence (RL) material Ga3+/Tb3+ metallacrowns (Tb‐1) is reported. This Tb‐1 crystal emits bright green luminescence under ultraviolet light or X‐ray excitation, and the emission intensity is 286 and 242 times that of Tb3+ in inorganic salt, respectively. Tb‐1 crystal is further passivated by trioctylphosphine oxide (TOPO), and the enhanced RL intensity is equivalent to that of commercial Tl‐doped cesium iodide scintillator. In addition, RL of Tb‐1–TOPO has an extremely narrow full width at half maximum and an excellent linear response to the X‐ray dose rate. The detection limit is calculated to be 0.146 μGy s−1, which is 38 times lower than typical medical imaging doses. Triplet‐enhanced lanthanide RL provides new ideas for replacing scintillators that require high temperature synthesis processes such as inorganic phosphors and ceramics, and provides a new alternative scintillator material for flexible X‐ray monitoring, bioimaging, radiotherapy, and other applications.