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Abstract It was reported that the UC emission intensity can be improved by introducing a thermal field and this phenomenon is highly related to the Yb3+ ions. Herein, we verify the thermal-induced UC enhancement degree can be further increased by separating the Yb3+ ions in the core and shell to promote the population of the defect energy level and inhibit the back energy transfer from Ho3+ to Yb3+ ions. Graphical abstract Image 1 Highlights • Thermal-induced enhancement degree of Ho3+ decreases with increasing Ho3+ doping content. • High Yb3+ content benefit the population of the defect energy level. • High Yb3+ content also induce back energy transfer from Ho3+ to Yb3+ions. • The enhancement degree is further increased by constructing core-shell structure. [ABSTRACT FROM AUTHOR]

Non-contact optical thermometry based on fluorescence intensity ratio (FIR) exhibits potential application in strong electromagnetic and corrosive environment. However, most of the reported systems exhibit high temperature sensitivity only at a narrow temperature range, which limit their practical application. In this work, a novel Ce 3+ /Mn 2+ /Eu 3+ tri-doped GdF 3 nano-thermometry based on different thermal behaviours between Eu 3+ and Mn 2+ ions is constructed. The calculated relative sensitivity in the whole measured temperature range are beyond 1.08% K −1 and the maximum S a is about 0.078 K −1 for the 50Ce/8Mn/2Eu: GdF 3 NCs, which are superior to several other inorganic nano-thermometry at the same temperature. In addition, these colorimetric temperature sensing materials exhibit potential application in anti-counterfeiting field as well. [ABSTRACT FROM AUTHOR]

In this work, Yb 3+ /Tm 3+ co-doped scheelite phosphors (NaGd(MoO 4 ) 2 ) are fabricated and explored as a potential temperature sensing material. The blue ( 1 G 4 → 3 H 6 ) and deep red ( 3 F 2, 3  →  3 H 6 ) emission bands of Tm 3+ ions exhibit opposite thermal dependent property, and therefore provide a self-referenced temperature sensing signals. Herein, we investigate the crucial factors for actualizing high temperature sensitivity in this system, and find that the temperature sensitivity can be well modified by manipulating the cross-relaxation between Tm 3+ ions. Finally, an optimized thermometric performance with the maxium relative sensitivity (S r ) of 1.86% K −1 at about 445 K–467 K is achieved, which is superior to previous upconverting thermometry. [ABSTRACT FROM AUTHOR]

Metal halide perovskites nanoparticles (PNPs) show promising application in X-ray detection and imaging. However, they exhibit poor stability, especially, the emission peak might be evidently shifted with increasing the PNPs concentration. In this work, the composites of CsPbBr 3 PNPs and BaLuF 5 : 15Gd/15Tb NPs are used to prepare scintillation film for the first time. When fixing the PNPs content in the film, its emission center is not changed after the addition of fluoride NPs. The uniform film containing both BaLuF 5 : 15Gd/15Tb to CsPbBr 3 is prepared. The scintillation intensity of the CsPbBr 3 PNPs is enhanced owing to the radiative energy transfer process from BaLuF 5 : 15Gd/15Tb to CsPbBr 3. Our results provide a novel route to improve the scintillation intensity, which might promote the exploration of new scintillators with high performance. • The composite of CsPbBr 3 and BaLuF 5 : Gd/Tb is used to prepare scintillation film. • The PL profile of CsPbBr 3 is not changed after the addition of fluoride NPs. • The RL intensity of CsPbBr 3 is enhanced owing to the radiative energy transfer. • The RL intensity of mixture is increased by ∼ 2.3 times compared to CsPbBr 3. [ABSTRACT FROM AUTHOR]

Highlights: [•] The Ln3+: NaGdF4 nanocrystals were synthesized based on the Ln3+: CaF2 precursors. [•] The microstructures of nanocrystals were characterized. [•] The multi-color upconversion emissions were easily realized. [ABSTRACT FROM AUTHOR]

Abstract: Single phase cubic BaLnF5 (Ln=La–Lu, Y) nanocrystals are successfully synthesized via a common facile solvothermal route using oleic acid as surfactant. It is found that the smaller the Ln3+ radius, the easier to precipitate the undesired BaLn2F8 phase in the reaction system along with the formation of BaLnF5. In this case, the appropriate reaction temperature is required to obtain single BaLnF5 nanophase. Measurements on the up-conversion emission behaviors of the Yb3+/Er3+ (Tm3+): BaLaF5 and Yb3+/Er3+ (Tm3+): BaLuF5 nanocrystals demonstrate that BaLnF5 are desirable up-conversion hosts. In addition, the Ce3+/Ln3+ (Ln=Tb, Eu, Dy, Sm): BaGdF5 nanocrystals are found exhibiting multicolor down-conversion emissions. [Copyright &y& Elsevier]

Abstract: The behavior of GaSb melt with tellurium addition was investigated using viscometer and differential scanning calorimetry (DSC). Normally, the viscosity of all melts measured decreased with the increasing temperature. However, anomalous transition points were observed in the temperature dependence of viscosity for Ga–Sb–Te system. Corresponded with the abnormal points on the viscosity–temperature curves, there were thermal effect peaks on the DSC curves. Furthermore, viscous activation energy and flow units of these melts and their structural features were discussed in this paper. [Copyright &y& Elsevier]

Toxic divalent lead ions are broadly chosen for famous perovskite systems with great optoelectronic performances, which motivates us to explore a novel strategy for its determination with high sensitivity. In this work, lanthanide doped inorganic oxysulfide nanocrystals (NCs) are verified to be excellent candidates for ratiometric Pb2+ ions sensing. Specifically, the photoluminescence (PL) intensity of Eu3+ ions in Y 0.4 Gd 1.6 O 2 S NCs decreases gradually with the increase of Pb2+ ions concentration under the excitation of 254 nm, while its intensity keep unchanged under 311 nm excitation. In this occasion, a ratiometric PL sensing route for Pb2+ ions is obtained through using I 311 as intrinsic reference. The detection limit for Pb2+ ions is 7.1 nM. This work provides a new ratiometric PL sensing route for Pb2+ ions via selectively non-radiative relaxation. • The PL intensity of Eu:Y 0.4 Gd 1.6 O 2 S NCs decreases with the addition of Pb2+ under 254 nm exicitation. • The PL intensity of Eu:Y 0.4 Gd 1.6 O 2 S NCs keep unchanged with the addition of Pb2+ under 311 nm exicitation. • A ratiometric PL sensing route for Pb2+ ions is obtained through using I 311 as intrinsic reference. • The detection limit for Pb2+ ions is 7.1 nM. [ABSTRACT FROM AUTHOR]

An pH-sensitive citric acid coated Ce/Tb:KGd 2 F 7 nanocrystals with a broad detection range from 3 to 10 is established. Under the 254 nm excitation, the Tb3+ emission intensity originated from Ce3+ → Gd3+ →Tb3+ decreases gradually with the increase of pH, while its intensity almost keeps unchanged in pH 3 to 6 and increases in pH 6 to 10 under the 311 nm excitation, which activates the ratiometric pH sensing with high sensitivity. An pH-sensitive citric acid coated Ce/Tb:KGd 2 F 7 NCs with a broad detection range from 3 to 10 is established. Under 254 nm excitation, the Tb3+ emission intensity decreases gradually with the increase of pH, while its intensity almost keeps unchanged below 6 and increased in pH 6 to 10 under 311 nm excitation. Image 1 • Citric acid coated Ce/Tb:KGd 2 F 7 NCs were prepared via a one-pot hydrothermal strategy. • Under the 254 nm excitation, the PL intensity decreases gradually with the increase of pH. • The intensity almost kept unchanged in pH 3 to 6 and increased in pH 6 to 10 under the 311 nm excitation. • A ratiometric pH sensing route with high sensitivity was obtained. [ABSTRACT FROM AUTHOR]

Biosensors working in the second near-infrared (NIR-II) spectral region have recently gained great attention owning to their deep tissue bioimaging and high spatiotemporal resolution. However, there is still a challenge to develop efficient nanothermometers based on NIR-II luminescence. Herein, we present a pioneering advancement in the field of nanothermometry by synthesizing a novel nanothermometer, a composite of fluoride nanocrystals and quantum dots. This NaYF 4 :1Nd-Ag 2 S QDs@SiO 2 nanocomposite demonstrates exceptional functionality, being excited by a single light irradiation at 808 nm for NIR-II luminescence imaging. Notably, the composite emits at two distinct wavelengths-1064 nm and 1125 nm, attributable to Nd3+ and Ag 2 S QDs, respectively. This unique emission profile enables deeper tissue penetration, mitigating overheating risks compared to conventional excitation sources at 980 nm. Furthermore, the nanomaterials exhibit remarkable temperature-sensing capabilities, with maximum sensitivities of 0.81%K−1 (S R) at 333 K. These superior sensitivities outperform many existing temperature sensors relying on thermally coupled Stark sublevels. The SiO 2 matrix not only encapsulates and protects the fluoride nanocrystals and quantum dots but also shields them from aqueous environments, ensuring outstanding luminescence stability. Our findings highlight the potential of this nanothermometer as a highly efficient temperature sensor with promising applications in cutting-edge bioapplications. This development introduces a new frontier in temperature sensing and bioimaging, showcasing its potential for transformative contributions to the field. [Display omitted] • Successful synthesis of a novel nanothermometer based on a composite comprising fluoride nanocrystals and quantum dots. • The emission intensity of Nd3+ and Ag 2 S QDs serves as a temperature sensing mechanism (0.81%K−1 (S R) at 333 K). • A versatile platform allows the integration of two different luminescent nanomaterials to meet customized requirements. • The SiO 2 matrix shields NCs and Ag 2 S QDs from water environments, ensuring excellent luminescence stability. [ABSTRACT FROM AUTHOR]

X-ray excited optical luminescence (XEOL) imaging shows great potential applications in security inspection and computed tomography. Lanthanide doped fluoride nanoscintillators (NSs) do not only exhibit advantages of simple synthetic procedures, tunable emissions and high environmental stability, but also show many new properties through constructing core/shell architectures. However, the strong hysteresis scintillation luminescence greatly restrict their practical applications. Herein, we verify that this hysteresis can be fully restricted by employing core/shell structure to inhibit the generation of Frenkel defects and incorporating Gd3+ ions to introduce extra energy migration process. As a result, upon continuous X-ray irradiation, the XEOL intensity of the LiYF 4 : 15Tb/25Gd@LiYF 4 core/shell NSs almost keeps unchanged. Our results provide important information for designing new NSs with greatly reduced hysteresis scintillation luminescence, which show promising applications in the field of stable X-ray imaging. [Display omitted] • Hysteresis scintillation is greatly restricted in the LiYF 4 : 15Tb/25Gd@LiYF 4 NSs. • Upon continuous X-ray irradiation, its XEOL intensity is only increased ∼1.6%. • The core/shell structure can inhibit the generation of Frenkel defects. • Incorporating Gd3+ ions can introduce extra energy migration process. [ABSTRACT FROM AUTHOR]

To achieve comfortable and healthy full-spectrum lighting, the development of efficient and stable violet-light-excitable phosphors is urgently required. Herein, we report a new type of green-emitting phosphor, Ba 1- x K x La 2 Y 2 (SiO 4) 2 O 1- α : Eu2+ (x =0–1). Interestingly, K+-alloying leads to continuous redshift of green emission from 500 nm to 517 nm accompanied with reduced full width at half maximum (FWHM) from 72 nm to 63 nm and enhanced excitation intensity in the violet spectral region. Rietveld refinements and spectral analysis evidence that K+-addition enhances the distortion of [M(Ⅰ)O 9 ] and [M(Ⅱ)O 7 ] (M(Ⅰ/Ⅱ) = Ba, La, Y, K) polyhedron and strengthens crystal field around Eu2+, which is responsible for the observed photoluminescence (PL) phenomenon. Finally, we design a full-spectrum white light emitting diode (WLED) with an ultra-high color rendering index (CRI, R a) of 97.4 by coupling the as-prepared green-emitting phosphor (Ba 0.7 K 0.3 La 2 Y 2 (SiO 4) 2 O 1- α : Eu2+) and commercial blue/red phosphors with a violet LED chip, which demonstrates significant potential for application in healthy solid-state lighting. [Display omitted] • A K+ alloyed Ba 1- x K x La 2 Y 2 (SiO 4) 2 O 1- α : Eu2+ phosphor has been developed. • The sample meets the requirements of commercial violet chip excitation LED. • The introduction of K+ ions improves the luminescence performance and thermal stability. • The full spectrum LED shows excellent performance. [ABSTRACT FROM AUTHOR]

• Co-based diamond composites were separately fabricated via the FDMS and the powder hot-pressed sintering technology. • There is a certain difference in the overall performance of the two kinds of specimens. • The Co-based samples fabricated by FDMS form a special coating state for diamond particles. • The Co-based samples fabricated by FDMS have defects of high porosity inside the matrix. • The reduction of knife-cut features can represent the improvement of density and holding ability of the FDMS sample. Fused deposition molding and sintering (FDMS) technology has the characteristics of low cost and low damage to diamonds. In order to explore more possibilities of additive manufacturing diamond tools, FDMS technology was considered to manufacture Co-based diamond composites at different temperatures in this paper. Also, specimens of Co-based diamond composites were manufactured under the same sintering process by using the powder hot-pressed sintering technology. And the matrix microstructure and properties of the specimens made by those two different technologies were analyzed and compared. The results show that a lot of porosity defects were developed inside the specimens manufactured by FDMS. This is because of the specific process characteristics of FDMS. Also, the matrix forms a special coating state for diamond particles due to the binder system used in this study, which causes some diamond particles to suffer slight thermal damage. These all will reduce the density and holding ability of the FDMS specimens. However, when the sintering temperature increases from 800 °C to 880 °C, the performance loss of FDMS samples caused by the porosity defects gradually decreases, thereby reducing the performance difference when comparing with the powder hot-pressed sintering specimens. In addition, the matrix structural uniformity of the FDMS specimens is significantly improved during this process, and the fracture feature changes from intergranular fracture to transgranular fracture. But there is still a certain difference in the overall performance of the two kinds of specimens at the optimal sintering temperature. Therefore, the further optimization of FDMS process parameters and binder system is of great significance for the application of FDMS in diamond tools. [ABSTRACT FROM AUTHOR]

In this work, a new dual-phase Ti-6Al-2Zr-2Mo-2 Nb-2Sn-1 V alloy was designed based on the classical Al-equivalent and Mo-equivalent design criteria, combined with the role of alloying elements in titanium alloys. The microstructure, microtexture and dynamic compressive properties of the alloy were studied systematically. A bimodal microstructure with 85 vol% α and 15 vol% β phase was obtained after annealing treatment. The equiaxed α phase (α p) and β phase conforms to Burgers orientation relationship (BOR), and part of lamellar α (α s) had similar orientations to the surrounding α p grains, resulting in the overlap of α p and α s texture components. The newly developed titanium alloy exhibited excellent dynamic compressive strength-plasticity-impact absorption energy matching, attributed to the coordinated deformation between α and β phases as well as α p and transformed β microstructure. The flow stress, plastic strain and impact energy at the critical failure strain rate of 4000 s−1 were 1586 MPa, 0.31 and 490 J/cm3, respectively. The dynamic mechanical properties of the new alloy are superior to those of typical titanium alloys and have the potential to be applied in high-strain rate environments. • New dual-phase Ti-6Al-2Zr-2Mo-2 Nb-2Sn-1 V alloy with excellent dynamic mechanical properties was designed. • α p and β phase conform to BOR, some α s and α p have similar orientations, causing the overlap of their textural compositions. • The dynamic mechanical properties of the designed alloy were superior to the existing typical titanium alloys. • Excellent dynamic mechanical properties was attributed to coordinated deformation between α and β phases and α p and β t. [ABSTRACT FROM AUTHOR]

A series of Er 3+ doped and Er 3+ /Yb 3+ codoped SrTiO 3 nanocubes with varying dopant concentrations have been successfully synthesized by a facile hydrothermal method. The doping effects on phase purity, morphology and microstructure of samples were identified by power X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results showed that SrTiO 3 nanocubes have a typical perovskite structure with the edge length ranging 20–50 nm. The Er 3+ and Yb 3+ ions were successfully doped into the crystal lattice of SrTiO 3 , but did not alter crystal structure of SrTiO 3 . The photon up-conversion (UC) photoluminescence (PL) measurements indicated that the intense green light emission of Er 3+ ions around 525 nm, 550 nm and red light emission centered at 670 nm in UC processes populated by 980 nm laser excitation have been achieved in SrTiO 3 nanocubes. Moreover, the PL intensity of Er 3+ -doped SrTiO 3 nanocubes was greatly enhanced while introducing the Yb 3+ to the crystal structure, especially the red emission. The mechanisms for these emissions probably due to the excited state absorption (ESA) and energy transfer (ET) process. Er 3+ /Yb 3+ -codoped single-crystal perovskite SrTiO 3 nanocubes could be interesting objects for applications in mechanical−electrical luminescence such as electric field modulation luminescence and mechanoluminescence. [ABSTRACT FROM AUTHOR]

As an additive manufacturing technology, Fused Deposition Modeling and Sintering (FDMS) technology can give diamond tools some creative structures to be applied in more fields. To explore the influence of diamond parameters on diamond tools manufactured by FDMS, copper-tin-diamond composite samples with different diamond concentrations and particle size were prepared by FDMS technology in this paper. During the study, the morphological characteristics of diamond particles inside the samples during the debinding and sintering process are summarized and the influence of diamond parameters on the mechanical properties and structure of the samples was further explored. These influence laws were also verified by cutting experiments. The results show that most diamond particles are in an incomplete coating state because of the volatilization of the binder. Meanwhile, a higher concentration of diamond will lead to more pores and cavities in the samples; and the cavities can be connected to form a large area of cavity zone by the print layer, thereby resulting in a serious loss in the performance of the samples. On the other hand, a small diamond particle size can lead to agglomeration of particles. Subsequently, this will result in void generation and regional weakening of the holding ability. However, agglomeration and some pores or cavities will increase the wear of the matrix, expose more diamond particles, and finally improve the cutting efficiency of the dicing blades when cutting sapphire crystal. Excessive wear may reduce the life of the diamond tool, but improved of sharpness can be better applied in the field of precision machining. • Higher concentration of diamond will lead to more pores and cavities. • The cavities will be connected and form a cavity zone due to FDMS process. • Agglomerates can lead to void generation and weakening of the holding ability. • Increased diamond concentration amplifies the effect of particle size on agglomeration. • Appropriate diamond parameters can prevent crack propagation. • Characteristic endowed by FDMS will improve the cutting efficiency of tools. [ABSTRACT FROM AUTHOR]

Aluminum alloys were used in various fields due to their high specific strength and low density. However, the disadvantage of low strength limits its wider application. In this work, the effect of ultrasonic surface rolling process (USRP) and artificial aging on microstructure and mechanical properties of 7075 aluminum alloy were investigated in detail. The results indicated that a multi-gradient nanostructure (MGNS) layer, i.e., grain gradient and precipitation gradient, was generated on the surface of the alloy. The tensile strength of the aged-USRP sample (692 MPa) was about 63 % higher than that of the coarse-grained sample (425 MPa), and the plasticity was comparable to that of the coarse-grained specimen. The underlying mechanisms of grain refinements, precipitation behavior and their effects on tensile properties were quantitatively analyzed. The high strength of the aged-USRP sample originated from grain boundary strengthening, precipitation strengthening, dislocation strengthening and synergistic strengthening. The activation of geometrically necessary dislocations (GNDs) during tensile deformation improved the plastic coordination ability of different microstructures. Thus, excellent strength-ductility synergy of 7075 aluminum alloy was obtained. • Multi-gradient nanostructure was formed on the surface of 7075 Aluminum Alloy. • Gradient nanostructure of type and number density of precipitates formed. • The multi-gradient nanostructure enhanced strength-ductility synergy of the alloy. [ABSTRACT FROM AUTHOR]

The corrosion resistance of 7075 aluminum (Al) alloy treated by ultrasonic surface rolling process (USRP) in a chloride environment was studied in this work. The effects of different USRP passes on the surface state (surface roughness and residual stress), surface microstructure, and corrosion resistance of this alloy were investigated through microstructural characterization, stress relaxation, immersion testing and electrochemical measurement. The results revealed that all USRP-treated samples demonstrated significantly improved corrosion resistance. However, the main factors that led to this performance enhancement were not the same. After 3 USRP treatment passes, the reduction in surface roughness and the increase in surface compressive residual stress improved the corrosion resistance of the 7075 Al alloy. After 7 USRP passes, the larger number of grain boundaries caused by surface grain nanocrystallization led to the rapid enrichment of passive elements, which formed a dense passive film on the alloy surface. At the same time, the dissolution of precipitates and the disappearance of precipitation-free zones (PFZ) reduced the corrosion caused by anodic dissolution. Meanwhile, the primary mechanism that controlled the corrosion rate was transformed from the surface state to the surface microstructure, which further improved the corrosion resistance of the 7075 Al alloy. • In our work, the surface state and surface microstructure of 7075 aluminum alloy are tailored by changing the ultrasonic rolling passes. • The corrosion resistance of 7075 Al alloy is significantly improved by ultrasonic surface rolling process (USRP) in this study. • The effects of surface roughness, residual stress, surface nanocrystalline and precipitates on the corrosion resistance of 7075 Al alloy after USRP are studied by stress relaxation and surface roughness analysis. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR) phosphors converted to light-emitting diodes (pc-LED) sources have extensive application prospects in medical imaging, foodstuff analysis and plant growth fields. However, there are some shortcomings in NIR phosphors, such as narrow emission band and poor thermal stability. Here a new wide band NIR luminescent phosphor Cr3+-doped Sr 3 Sc 4 O 9 (SSO) is introduced. The emission spectrum ranges from 600 nm to 1000 nm, with a peak value of 761 nm and the value of full width at half maximum (FWHM) is 120 nm. The internal quantum efficiency (IQE) of sample is about 87% according to the fitting result. The most appropriate doping concentration is x = 0.02 and the best excitation wavelength is 468 nm, which matches the commercial blue chip. At the same time, the phosphor shows good thermal stability in variable temperature spectrum test, and can maintain 70.4% emission intensity at 373 K relative to room temperature. To better understand its practical applications, packaged pc-LED is designed to show good NIR light penetration in spectral penetration tests. This study provides an excellent choice of NIR phosphors. • Sr 3 Sc 4 O 9 :Cr3+ phosphors are promising near-infrared (NIR) emission materials. • The phosphors retain 70.4% of initial emission intensity at 373 K. • The IQE of sample is about 87%. • The pc-LED device can be applied in NIR penetration analysis. [ABSTRACT FROM AUTHOR]

Abstract: The novel Eu3+:CeO2 hollow microspheres are successfully fabricated by a facile and green route, employing the colloidal carbon spheres as sacrificial templates. In the coating process, the large amount of hydrophilic functional groups are beneficial to the adsorption of Ce3+, Eu3+ and OH− to form the initial amorphous precursors on the surfaces of the carbon spheres. When heat-treated at appropriate temperature, the carbon spheres in the cores are burned away, while the precursors in the shell crystallize to the Eu3+:CeO2, forming a hollow structure. The Eu3+ ions occupy the Ce sites in the CeO2 lattice, and yield intense red emissions under 340nm excitation. This material of hollow microspheres may find potential applications in the field of color display. [Copyright &y& Elsevier]

In order to study the optical temperature sensing characteristics of phosphors with dual emission centers, a series of La 2 MgGeO 6 : Bi3+, Mn4+ phosphors were prepared by solid phase method at high temperature. Due to the different thermal responses of Bi3+ and Mn4+ ions, the fluorescence intensity ratio between the double emission centers is expected to be an effective method for temperature sensing. The structural phase and luminescence properties of the samples were characterized by X-ray powder diffraction, field emission scanning electron microscopy, ultraviolet spectrophotometer and fluorescence spectrometer. According to the structure of La 2 MgGeO 6 host, it can be seen that Bi3+ ion can replace La3+ ion and Mn4+ ion can replace Ge4+ ion because the valence state of ions are the same and the ion radius is close. Through the excitation of ultraviolet light, La 2 MgGeO 6 : Bi3+, Mn4+ present two emission bands, which correspond to the Bi3+ ions 3P 1 → 1S 0 transition (emitting blue light) and Mn4+ ions 2E g → 4A 2g transition (emitting red light) respectively. Moreover, there is energy transfer from Bi3+ ions to Mn4+ ions. Based on the different temperature responses of Bi3+ blue emission and Mn4+ red emission, their fluorescence intensity ratio was used to discuss the temperature measurement characteristics. The absolute sensitivity and relative sensitivity of La 2 MgGeO 6 : Bi3+, Mn4+ phosphors reached the maximum value of 1.419% K−1 at 473 K and 3.027% K−1 at 383 K in the temperature range of 293–473 K. Therefore, La 2 MgGeO 6 : Bi3+, Mn4+ phosphors are excellent materials for optical temperature measurement. • The novel LMGO: Bi3+, Mn4+ phosphors with dual-emitting centers were prepared by high-temperature solid-phase method in air. • The LMGO: Bi3+, Mn4+ shows high signal discriminability in the blue and red regions. • The LMGO: Bi3+, Mn4+ phosphors can circumvent the drawbacks of TCL-based phosphors. • The maximum S r of the LMGO: Bi3+, Mn4+ phosphors can reach 3.027% K−1 at 383 K. • The thermal-quenching mechanism of Bi3+ and Mn4+ were discussed. [ABSTRACT FROM AUTHOR]

Hydrothermal reaction of Zn(NO 3) 2 ·6H 2 O with a flexible bipyridyl ligand, (pyridin-4-yl)methyl 3-(2-(4-((pyridin-4-yl)methoxy)phenyl)diazenyl)benzoate (L) and 1,3-benzenedicarboxylic acid (1,3-H 2 BDC) gave rise to a novel metal-organic framework (MOF), {[Zn (1,3-BDC)L]∙H 2 O} n. The as-synthesized MOF has been characterized by Fourier transformed infrared (FT-IR), powder X-ray diffraction, single-crystal X-ray diffraction and scanning electron microscopy (SEM). By introduction of the ligand L containing ester, diazene and ether groups, a large number of oxygen and nitrogen sites that can be readily protonated in acidic conditions were successfully decorated on the surfaces of the predesigned MOF. The as-prepared protonated Zn-MOF with abundant positive charges (−N NH+−, –OH+−, –COOH+−) was applied as an adsorbent to remove anionic dyes from aqueous solutions. Such an adsorbent exhibited ultrahigh uptake capacities for different sized anionic dyes of Amido Black 10 B (AB, 2402.82 mg g−1), Methyl Orange (MO, 744.02 mg g−1), Orange ΙΙ (OII, 522.83 mg g−1) and Direct Red 80 (DR, 1496.34 mg g−1). The anionic dyes uptakes of the adsorbent are obviously higher than that of most reported adsorbents. Moreover, the adsorbent showed excellent selectivity in the adsorption of anionic dyes. The adsorption process followed the pseudo-second-order kinetics. The equilibrium adsorption isotherm data were well fitted by Langmuir and Sips models. FT-IR, zeta potential analysis and SEM investigation revealed that the interactions between the protonated Zn-MOF and the anionic dyes are mainly dominated by electrostatic interaction and surface adsorption. This work may provide a new perspective for the development of functional materials on the removal of contaminants from water environment. Image 1 • Ester, diazene and ether decorated metal-organic framework (MOF) was constructed. • The functionalized MOF can be readily protonated in acidic condition. • The grinded samples can be broken into nanoparticles and well disperse in water. • It showed excellent adsorption performance for different sized anionic dyes. [ABSTRACT FROM AUTHOR]