The influence of NH₄⁺ ions on the corrosion behavior of AZ31 magnesium alloy was investigated by immersion test, hydrogen evolution, electrochemical methods and morphology observation. The results demonstrate the acceleration effect of NH₄⁺ on corrosion of AZ31 magnesium alloy due to the disruption of protective MgO film in NH₄⁺-containing solution. The loose and cracked corrosion products of AZ31 magnesium alloy in NH₄⁺-containing solutions are mainly composed of (Mg_0.833Al_0.167)(OH)₂(CO₃)_0.083·0.75H₂O and Mg₅(CO₃)₄(OH)₂·5H₂O. When the NH₄⁺ concentration is lower than 0.01 M, knife-cut like corrosion occurs in some active area of the surface due to the partial dissolution of MgO layer. As the NH₄⁺ concentration is increased to 0.1 M, the MgO layer is completely disrupted, resulting in the occurrence of uniform corrosion. Both cathodic and anodic reactions are accelerated by NH₄⁺ ions, while the effect of original pH values on the reaction kinetics can be neglected in NH₄⁺-containing solutions.

High-entropy amorphous alloys present high hardness, but low tensile ductility. Here, deformation behavior of the amorphous/crystalline FeCoCrNi high-entropy alloy (HEA) composite prepared by the previous experiment is investigated using atomic simulations. The result shows the partial dislocations in the crystal HEA layer, and the formation of shear bands in the amorphous HEA layer occurs after yielding. The strength of the amorphous/crystalline HEA composite reduces with increasing the thickness of the amorphous layer, agreeing with the previous experiments. The coupled interaction between the crystal plasticity and amorphous plasticity in amorphous/crystalline HEA composites results in a more homogeneous redistribution of plastic deformation to cause interface hardening, due to the complex stress field in the amorphous layer. The current findings provide the insight into the deformation behavior of the amorphous/crystalline HEA composite at the nanoscale, which are useful for optimizing the structure of the HEA composite with high strength and good plasticity.

For the first time in this work, we manage to synthesize single-crystalline NaNb_0.875Ta_0.125O₃ wires by combining the advantages of one-dimensional (1D) nanostructure and heteroatom doping strategy. Careful Ta doping was performed to figure out the correlation between morphological and structural evolution as well as the photocatalytic performance towards H₂ generation. It was found that, the as-prepared NaNb_0.875Ta_0.125O₃ wires presented a highest and stable photocatalytic performance, which was appropriately 41 and 2 folds higher than that of bare NaTaO₃ and NaNbO₃. The optical activity was mainly ascribed to the synergistic effect between appropriate Ta doping and perfect 1D wire-like morphology, which resulted in fewer defects, improved charge transfer efficiency and higher reduction capability of electrons. On the other hand, a possible photocatalytic mechanism of photocatalytic H₂ production was proposed in detail. This work creates a new perspective into designing multi-component materials and understanding the mechanism of H₂ evolution, which offers new opportunities for solar-energy conversion.

Ti-23Nb-0.7Ta-2Zr-O gum metal (GM) is an attractive candidate material for applications that require superior mechanical properties. In our earlier investigation of the GM [1], geometrical softening and the generation of adiabatic shear bands (ASBs) were proposed as primary reasons for the documented anisotropic impact response. In the present study, electron backscattered diffraction (EBSD) analysis reveals two different deformed microstructures, i.e., deformed ultrafine grains (UFGs) and dynamically recrystallized UFGs, formed in the ASBs of GM samples processed by extrusion equal channel angular pressing (ECAP), respectively. Additional calculation of temperature rise during dynamic compression suggests that the above microstructure differences in the ASBs was originated from their different maximum ASB temperatures (608?K for extruded GM and 1159?K for ECAP-processed GM). Moreover, our calculation on the temperature at the onset of ASBs indicates that microstructural softening is the primary cause for the development of ASBs in both extruded GM (321?K) and ECAP-processed GM (331?K).

The interplay and intergrowth characteristic of faceted intermetallic compounds (IMCs) during solidification was originally investigated through the rod-like Al₃Ni crystals in the liquid Al/solid Ni interconnection by using synchrotron radiography, and the diversified 3-D morphologies were reconstructed by synchrotron tomography. A spatial geometric model was established to effectively predict the diversified growth patterns of two spatial crystals. For the two overlapping Al₃Ni crystals, the impeded crystal growth was divided into three different stages, decided by the hindrance form the other crystal. Further, the groove formed on the crystal surface is directly related to the solute redistribution under the critical condition of boundary layer thickness larger than two crystals distance. The closer distance and smaller crystal size indicate the deeper and larger groove, and the morphology changes from hemispheroid to hemi-ellipsoid with the increased opposite and interacted faces.

A full-duplex radiant energy converter based on both betavoltaic and photovoltaic effects in an easy-to-implement way is an attractive alternative for the autonomous wireless sensor microsystem. Here, we report a novel beta/photovoltaic cell based on free-standing ZnO nanorod arrays (ZNRAs) modified with metallic single-walled carbon nanotubes (m-SWCNTs), using radioisotope⁶³Ni as beta-emitting source. The ZNRAs were grown on Al-doped ZnO (AZO) conductive glass using hydrothermal method. The optimum length and diameter of ZnO nanorods were determined by Monte Carlo simulation for beta energy deposition in ZNRAs. The m-SWCNTs were anchored into the ZNRAs to form a three-dimensional (3-D) Schottky junction structure for effectively separating the beta/photo-excited electron-hole pairs. Experimentally, the betavoltaic and photovoltaic effects were confirmed through the I-V measurements of beta/photovoltaic cells under beta/UV/Vis irradiations, respectively. It is suggested that the m-SWCNTs play key role for the enhancement of beta/photovoltaic performance through the formation of extensive 3-D Schottky junction, the conductive network for hole transport, and the surface plasmon resonance exciton absorption for visible light.

One of the most desired strengthening mechanisms in the carbon nanotube reinforced aluminum matrix composites (CNT/Al) composites is the load transfer strengthening mechanism (LTSM). However, a fundamental issue concerning the LTSM is that quantitative measurements of load partitioning in these composites during loading are very limited. In this study, in-situ neutron diffraction study on the tensile deformation of the 3 vol.% CNT/2009Al composite and the unreinforced 2009Al alloy was conducted. The {311} and {220} diffraction elastic constants (DECs) of the 2009Al alloy were determined. Using those DECs the average stress in the 2009Al matrix of the composite was calculated. Then the average stress in the CNTs was separated by using the stress equilibrium condition. Computational homogenization models were also applied to explain the stress evolution in each phase. Predicted results agree with experimental data. In the present case, the average stress in the CNTs reaches 1630 MPa at the yield strength of the composite based on linear regression of the measured data, which leads to an increment of yield strength by about 37 MPa. As the result of this work, an approach to quantify load partitioning in the CNTs is developed for the CNT/Al composites, which can be applied to optimize the mechanical properties of the composites.

Rational design has been widely used to develop high-performance metal selenides-based electrode materials for supercapacitors. In this study, we develop a facile one-step solvothermal approach to synthesize binder-free Ni₃Se₂ nanodendrite arrays grown on nickel foam as advanced positive electrodes for supercapacitors. Our Ni₃Se₂ nanodendrite arrays on nickel foam exhibit a specific capacitance of 1234 F g^-1 (3.70 F cm^-2) at a current density of 1 A g^-1 and a great rate capability, which is benefited from the excellent electrical conductivity and unique hierarchical nano-dendritic structure. Furthermore, an asymmetric supercapacitor device was assembled using activated carbon as the negative electrode and the Ni₃Se₂ nanodendrite arrays on nickel foam as the positive electrode, obtaining a high energy density of 22.3 W h kg^-1 at a power density of 160.4 W kg^-1.

The Ni-rich layered LiNi_0.6Mn_0.2Co_0.2O₂ (NMC622) is one promising cathode for lithium-ion batteries (LIBs), but suffers from poor cycling stability under high cutoff potentials. The performance degradation was reflected as capacity fading and voltage drop, having their roots in instable interface of NMC622. Aimed at improving interfacial stability, in this study, we deposited nanoscale ZrO₂ coatings conformally over NMC622 cathodes using atomic layer deposition (ALD). We found that, under a high cutoff voltage (4.5 V), the ALD ZrO₂ coatings evidently improved the performance of NMC622 cathode, showing better cyclability and higher sustainable capacity. In addition, the ALD coatings dramatically boosted the rate capability of NMC622. All these compelling performance results are ascribed to the atomic-scale tunable ZrO₂ coatings via ALD, which create stable interface and thereby inhibit unfavorable evolutions. In the study, we utilize a suite of characterization tools and various analyses to clarify the effects of ALD ZrO₂ coatings. This study will be helpful for improving the performance of nickel-rich cathodes via interfacial engineering using ALD.

Failure strain determination of polymer-supported thin films is a key for the design of the flexible devices. A theoretical model R/R₀=(L/L₀) ² (R, L are the electrical resistance and the length of the stretched film, respectively. R₀, L₀ are the corresponding initial values.) has been widely used to determine the fracture strain of thin films on flexible substrates. However, this equation loses its function in some special cases. Here, a simple and universal theoretical model was proposed to determine the fracture strain of metal thin films on flexible substrates in more generally situations. With this model, we investigated the thickness-dependent failure strains of Cu-5 at.% Al films with thickness of 10 nm, 200 nm, 1000 nm, and Ti films with thickness of 50 nm, 100 nm, 300 nm. This model was also employed to study the published data available. The results showed that the new model provided a fairly good prediction of the failure strains of different films.

The effect of in-situ local damage of uniform porous corrosion products on the localised corrosion of carbon steel is investigated using the wire beam electrode technique (WBE) combined with morphology characterisation and electrochemical tests. The WBE measurements demonstrate that the localised corrosion is enhanced by the in-situ local removal of porous corrosion products, supported by the morphology characterisation and electrochemical tests. The enhanced localised corrosion does not originate from the damaged wire in WBE where the corrosion products are removed but from the other undamaged wires, which is reported for the first time. A mechanism is proposed that the intensive anodic polarisation effect of the damaged wire on the undamaged wires could account for the enhanced localised corrosion, which is due to the protective corrosion products newly formed on the damaged surface and the increase in the potential of damaged wire.

H₂ is considered an indispensable component of the atmosphere for the growth of high-quality single-wall carbon nanotubes (SWCNTs) by chemical vapor deposition. However, details of the roles H₂ playing are still unclear due to the complex conditions of SWCNT growth. In this study, we elucidate the functions of H₂ in the selective growth of semiconducting SWCNTs (s-SWCNTs) by using monodispersed uniform Fe nanoparticles as a catalyst. High-quality s-SWCNTs were synthesized by finely tuning the concentration of H₂ and the other growth parameters. Experimental data combined with atomistic simulations indicate that H₂ not only adjusts the concentration of the carbon source, but also serves as a mild etchant that selectively removes small carbon caps grown by a perpendicular mode from the Fe nanoparticles. These results provide useful hints for the controlled growth of SWCNTs with a semiconducting or metallic conductivity, and even a specific chirality.

La- and Nb-doped BaTi₂O₅ (BT₂) spherical glasses were prepared by a containerless aerodynamic levitation method and their glass-forming regions were established. It is found that La-doping on the Ba-site (network-modifier) and Nb-doping on the Ti-site (network-former) show distinct difference in the glass-forming region: less than 10 % La can replace Ba whereas 40 % Nb can incorporate into BT₂ glass. The distinction in glass-forming ability induced by La- and Nb-doping is discussed mainly from the structural arrangement of the glass. Raman spectroscopy analysis shows that La-doping elongates the short Ti-O bonds in the distorted [TiO₅] polyhedra and thus relaxes the network. Nb-doping introduces [NbO₆] polyhedra into BT₂ and there exists a critical doping level (20 %), below which incorporation of Nb into BT₂ relaxes the [TiO_n] polyhedra by shortening the long Ti-O bond and above which [NbO₆] starts to participate in the network skeleton construction resulting in a dramatic change in the glass structure, which is supported by the dramatic change in the exothermic peak on the DTA curves. This work triggers the speculation that the network-modifiers in BT₂ glass possess a very important role in the structure of network-former skeleton than those in glasses based on traditional network-former oxides such as SiO₂, GeO₂ and B₂O₃, which may provide a useful strategy for modifying the properties of these novel glasses by chemical doping.

The environment at crack tip and its effect on the crack growth behaviour of low alloy steel- E690 steel were studied at cathodic potentials in artificial seawater. The results showed that the micro environment at crack tip and crack growth behaviour were related to the electrochemical reactions at crack tip, which were affected by the stress state and applied potentials. The crack tip environment was acidified under cyclic loading, resulting from the crack tip anodic dissolution reaction and corresponding hydrolysis reaction. Because of the hydrogen evolution and the inhibited anodic dissolution inside the crack, the crack tip pH increases as the cathodic potential decreases. The effect of cathodic potentials on the electrochemical reactions caused the variation of the hydrogen content, which influenced the crack growth rate because the crack growth behaviour was controlled by hydrogen embrittlement mechanism. This resulted in a fact that with the negative decrease of potential, the crack growth rate first decreased and then increased, with the minimum rate at -0.75 V. And the crack growth path exhibited transgranular fracture.

A low-diffusion NiRePtAl coating ((Ni,Pt)Al outer layer in addition to a Re-rich diffusion barrier layer) was prepared on a Ni₃Al-base single crystal (SC) superalloy via electroplating and gaseous aluminizing treatments, wherein the electroplating procedures consisted of the composite deposition of Ni-Re followed by electroplating of Pt. In order to perform a comparison with conventional NiAl and (Ni,Pt)Al coatings, the cyclic oxidation performance of the NiRePtAl coating was evaluated at 1100 and 1150 °C. We observed that the oxidation resistance of the NiRePtAl coating was significantly improved by the greater presence of the residual β-NiAl phase in the outer layer and the lesser outward-diffusion of Mo from the substrate. In addition, the coating with the Re-rich diffusion barrier demonstrated a lower extent of interdiffusion into the substrate, where the thickness of the second reaction zone (SRZ) in the substrate alloy decreased by 25 %. The mechanisms responsible for improving the oxidation resistance and decreasing the extent of SRZ formation are discussed, in which a particular attention is paid to the inhibition of the outward diffusion of Mo by the Re-based diffusion barrier.

Two-dimensional Ti₃C₂T_x flakes have great application potential in various areas due to their optical, electronic, electrochemical and mechanical properties, but their anti-corrosion and wear-resistance performance were not well understood. The difficulties in achieving good dispersity and interface interaction of inorganic additives in organic coatings hinder the incorporation of Ti₃C₂T_x into the epoxy coating. Here, few-layered Ti₃C₂T_x sheets with amino-functionalization were prepared, and as reinforced-additives were added into the waterborne epoxy coating. Anti-corrosion and tribological properties of as-prepared composite coatings were investigated in detail. The results reveal that the composite coating with 0.5 wt.% amino-functionalized Ti₃C₂T_x sheets shows excellent corrosion protection (the lowest frequency impedance was 3.12 × 10⁹ Ω cm ²) and wear resistance (wear rate was reduced by 72.74%). The greatly improving performance of composite coatings mainly depends on: (a) good dispersity and compatibility of amino-functionalized Ti₃C₂T_x in organic matrix, (b) high adhesion strength between coating and metal substrate and (c) the intrinsic properties of Ti₃C₂T_x sheets. The work provides a good path for applications of MXene as multifunctional additives.

Mg-13.1Gd-1.6Ag-0.4 Zr (wt%) alloy was either iso-thermally extruded at 350 °C or differential-thermally extruded with respectively pre-heated billet at 500 °C and die at 350 °C. The iso-thermal extrusion leads to a near fully recrystallized structure and a [0001]//ED (extrusion direction) texture. In contrast, the differential-thermally extruded alloy develops a bimodal-grained structure composed of fine equiaxed recrystallized grains and coarse elongated unrecrystallized grains with a 011ˉ0//ED texture. The differential-thermally extruded alloy has a higher number density of precipitates after post-extrusion ageing than that of the iso-thermally extruded counterpart. Moreover, precipitation in the differential-thermally extruded alloy is further enhanced with cold rolling before ageing. Finally, the alloy obtains room temperature tensile yield strength of 421 MPa and ultimate tensile strength of 515 MPa via differential-thermal extrusion, cold rolling and ageing, mainly ascribed to the coupled strengthening from the bimodal-grained structure and enhanced precipitation. Strength of the alloy is noticeably higher than those of Mg-Gd(-Y)-Ag extruded alloys with similar compositions reported previously and is comparable to those of other high-strength Mg wrought alloys. The findings suggest that differential-thermal extrusion plus strain ageing is a suitable approach for achieving high strength in age-hardenable Mg alloys.

The 93W and Mo1 refractory metals were bonded with different Cu_1-xNi_x coating interlayers of various Ni content using plasma-activated sintering at 700?°C. The effects of the Ni content in the Cu_1-xNi_x coating interlayer on the interfacial microstructure evolution and mechanical properties of the W/Mo joints were studied. The maximum average shear strength of the W/Mo joint was 316.5?MPa when the Ni content of the Cu_1-xNi_x coating interlayer was 25 %. When the Ni content of the Cu_1-xNi_x coating interlayer was below 50 %, the atomic diffusion at the W/Mo joint interface was adequate without the formation of intermetallic compounds, as demonstrated by the High Resolution Transmission Electron Microscope analyses of the joints. The presence of Ni in Cu_1-xNi_x promoted diffusion bonding at the interface, which contributed to the high mechanical properties of the W/Mo joint. With an increase in the Ni content of the Cu_1-xNi_x coating interlayer, the MoNi intermetallic compound (IMC) nucleated and grew at the Cu_1-xNi_x coating/Mo1 interface. When the Ni content of the Cu_1-xNi_x coating interlayer was above 50 %, the generation of a brittle MoNi IMC weakened the shear strength of the W/Mo joint dramatically.

TiO₂-B/anatase nanotubes doped by vanadium have been synthesized through a facile one-step hydrothermal reaction. The material shows a mesoporous structure with a specific surface area of 179.1 m² g^-1. XPS data presume the presence of V³⁺, V⁴⁺, V⁵⁺, and Ti³⁺ in doped TiO₂-B/anatase. As found by XRD and EIS investigations, the vanadium expands bronze titania crystal structure and enhances the conductivity of material by three orders of magnitude. When tested for lithium storage, the V-modified titania nanotubes show a specific capacity of 133 mA h g^-1 after 100 charge/discharge cycles at the current density of 3000 mA g^-1 with a Coulombic efficiency of around 98.9%, resulting in its good cycleability. The material still possesses a reversible capacity of 114 mA h g^-1 at a very high current load of 6000 mA g^-1, demonstrating superior rate characteristics for secondary lithium batteries. Furthermore, V-doped TiO₂-B/anatase mesoporous nanotubes show promise performance as anode material for sodium-ion batteries, delivering about 119 mA h g^-1 and 101 mA h g^-1 at the current loads of 10 and 1500 mA g^-1, respectively.

Large size polysynthetically twinned crystals of Ti-46Al-8Nb alloy with a parallel lamellar microstructure were successfully prepared using a Ti-43Al-3Si seed by our new operation. A large amount of columnar B2 phase paralleling to the growth direction was found in the final lamellar microstructure. Higher growth rate (>30?mm/h) led to the failure of seeding process. Based on these results, a new mechanism is proposed to describe the seeding process of the hypo-peritectic TiAl alloys. The peritectic α phase is suggested to directly nucleate from the melt, and then act as nucleus for transformed α phase in the subsequent β to α transformation. At the higher growth rate, the appearance of β phase secondary dendrites and homogeneous nucleation lead to the failure of seeding process. High Nb addition leads to a large amount of residual β phase, and these β dendrites finally evolve into B2 phase. The room temperature tensile elongation was measured to be 11.9-18.5% for Ti-46Al-8Nb PST crystals, which is the highest ever reported value for TiAl based alloys.

In the present study, we selected solutes to be added to the CrCoNi medium-entropy alloy (MEA) based on the mismatch of self-diffusion activation energy (SDQ) between the alloying elements and constituent elements of the matrix, and then investigated their grain growth behavior and mechanical properties. Mo and Al were selected as the solutes for investigation primarily because they have higher and lower SDQ, respectively, than those of the matrix elements; a secondary factor was their higher and lower shear modulus. Their concentrations were fixed at 3 at.% each because previous work had shown these compositions to be single-phase solid solutions with the face-centered cubic structure. Three alloys were produced by arc melting, casting, homogenizing, cold rolling and annealing at various temperatures and times to produce samples with different grain sizes. They were (a) the base alloy CrCoNi, (b) the base alloy plus 3 at.% Mo, and (c) the base alloy plus 3 at.% Al. The activation energies for grain growth of the CrCoNi, CrCoNi-3Mo and CrCoNi-3Al MEAs were found to be ～251, ～368 and ～219?kJ/mol, respectively, consistent with the notion that elements with higher SDQ (in this study Mo) retard grain growth (likely by a solute-drag effect), whereas those with lower values (Al) accelerate grain growth. The room-temperature tensile properties show that Mo increases the yield strength by ～40 % but Al addition has a smaller strengthening effect consistent with their relative shear moduli. The yield strength as a function of grain size for the three single-phase MEAs follows the classical Hall-Petch relationship with much higher slopes (＞600?MPa μm^?0.5) than traditional solid solutions. This work shows that the grain growth kinetics and solid solution strengthening of the CrCoNi MEA can be tuned by selecting solute elements that have appropriate diffusion and physical properties.

The spontaneous growth of metal whiskers has been investigated for more than 70 years. However, there is still no agreement on its growth mechanism, and moreover, new characteristics of this whiskering phenomenon continue to emerge. In this study, Ti₂SnC is found to be capable of extracting Sn out of its alloys (SnBi, SnAg) by selectively growing Sn whiskers, and the Sn whiskers share the features of the traditional whiskers on platings and solders. Replacing the Ti₂SnC substrate with TiC or SiC, under the same conditions, however, the selective growth of Sn whisker does not happen, which means Ti₂SnC plays a critical role in it. Based on the unique crystal structure of Ti₂SnC, active Sn atoms diffusing through the basal planes of Ti₂SnC is proposed to explain the selectivity. The driving force is suggested to be the high interfacial energy between Ti₂SnC and tin. This study is of importance to further understand the growth mechanism of metallic whiskers, and it may be also possible to be harnessed to develop paradigm-shifting technologies of metal purification and metallic whisker/nanowire preparation.

The NiCrAlTi coatings free of N and with N incorporations were deposited on austenitic stainless steel 304L by magnetron sputtering in Ar and in gas mixture of Ar and N₂, respectively. The N incorporated in the coatings existed as nitride precipitates (from ～3 vol.% to ～17 vol.%) after vacuum annealing. All the NiCrAlTi coatings, whatever free of N or with N incorporations, exhibited better resistance against cavitation erosion than ion plating TiN coating and the substrate 304 L in ultrasonic cavitation tests. The NiCrAlTi coating free of N incorporation presents superior cavitation erosion resistance. However, the nitrogen incorporation within the NiCrAlTi coatings showed negative effects on the resistance against cavitation erosion.

Porous SiOC ceramic was successfully prepared by pyrolysis of dimethylsilicone oil, silane coupling agent and melamine foam. The microwave absorbing properties of porous SiOC were studied for the first time. At the matching layer thickness of 3.0 mm, the paraffin-based composite with porous SiOC displays a minimum reflection coefficient (RC) of -39.13 dB (11.76 GHz) and an effective absorption bandwidth (EAB) of 4.64 GHz which are much larger than that of paraffin-based composite with ordinary SiOC. It is found that the porous structure of SiOC is crucial to achieve its high microwave absorption performance by improving both the polarization loss and conduction loss. The enhanced polarization loss is originated from the dipole polarization and interfacial polarization, while the improvement of conduction loss is attributed to the carbon skeleton of porous SiOC. These results indicate that porous SiOC ceramic is a promising candidate for high-performance ceramic-based microwave absorbing materials.

The novel single Dy³⁺-activated and Dy³⁺/Eu³⁺ co-activated LaSr₂F₇ NPs-based phosphors were successfully synthesized via a simple precipitation reaction method at room temperature. The phase formations and cell parameters of single Dy³⁺-activated and Dy³⁺/Eu³⁺ co-activated LaSr₂F₇ NPs were verified in detail by the Rietveld refinement technique based on the recorded X-ray diffraction patterns. The doping concentration of single Dy³⁺-activated LaSr₂F₇ NPs was optimized to be 0.1 mol with the concentration quenching dominated by the electric dipole-dipole interaction. Meanwhile, a variety of Eu³⁺-activated La_0.9Sr₂F₇:0.1Dy³⁺ NPs exhibited tunable luminescent properties and emitted warm white light in close to standard warm white light under 363 nm excitation. The valid energy transfer (ET) efficiency from Dy³⁺ to Eu³⁺ ions was estimated to be about 86.02% based on the emission intensity while the electric dipole-quadrupole interaction dominated the concentration quenching mechanism in ET process. Eventually, the thermal quenching of the obtained samples was studied, showing the excellent thermal stability. All the results manifest that Eu³⁺-activated LaSr₂F₇:Dy³⁺ NPs could emit warm white light with excellent thermal stability for indoor illumination.