Aluminium and cerium co-doped ZnO nanoparticles:Facile and inexpensive synthesis and visible light photocatalytic performances

Facile combustion route synthesized Al and Ce co-doped ZnO nanoparticles photocatalysts were characterized using XRD,SEM,BET,EDS,UV-visible DRS,PL,photocurrent and EIS techniques.XRD and SEM analyses identify that crystallite and particle size is reduced from 13.26 to 11.88 nm with introduction of Al and Ce into ZnO which assists inhibiting the recombination of photo generated charge carriers.UVvisible DRS spectra indicate that optical assimilation of ZnO is significantly increased to visible region(-406 nm)and band gap reduces from 3.18 to 3.06 eV with introduction of Al and Ce co-dopants.Electrochemical impedance spectroscopy analysis under visible light illumination confirms the enhancement in visible light activity of Al and Ce co-doped ZnO nanoparticles as photocatalysts.The enhanced activity of Al and Ce co-doped ZnO photocatalyst can be ascribed to enhanced light assimilation,high surface area and efficient charge transfer process.Our results reveal that by incorporating precise amount of Al(~2%)and Ce(~2%)into ZnO,a highly efficient catalyst can be synthesized that have degraded almost 95%methyl orange(MO)dye in just 45 min.Further,the influence of various operational parameters such as solution pH,catalyst dose,dye concentration,airflow rate and light intensity on photodecomposition of MO was evaluated.Furthe rmore,a possible mechanism for Al and Ce modified ZnO was proposed and designed photocatalysts demonstrates good stability in aqueous medium.     

Preparation of cerium and yttrium doped ZnO nanoparticles and tracking their structural,optical, and photocatalytic performances

Yttrium(Y) and cerium(Ce) co-doped ZnO nanoparticles(NPs) were synthesized via the simple sol-gel auto-combustion route.The effect of Ce and Y doping on the structure,morphology,optical,Zeta potential,and photocatalytic activities of ZnO NPs was examined by Fourier transform infrared(FTIR)spectrometer,X-ray diffraction(XRD),transmission electron microscope(TEM),UV-vis spectrophotometer,and Zetasizer instrument.XRD data show that the fabricated samples crystallize into a hexagonal wurtzite struct...     

Preparation and application of ZnO doped Pt-CeO2 nanofibers as electrocatalyst for methanol electro-oxidation

ZnO doped Pt/CeO₂ nanocomposites were prepared by electrospinning and reduction impregnation. X-ray diffraction (XRD), transmission electron microscopy (TEM), energy disperse spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) were employed to characterize the nanocomposites. It is observed that ZnO and CeO₂ form the hexagonal wurtzite phase and cubic fluorite phase in the nanocomposite, respectively, whilst Pt nanoparticles (NPs) with the number-averaged size of ca. 3.1 nm are uniformly distributed on the surface of nanofibers. The mass fraction of Pt NPs in the nanocomposites is about 10 wt%. The doping of ZnO is effective to promote reactive oxygen species, surface reaction sites and the interaction between Pt and oxides. The catalytic performance of nanocomposites was evaluated by the methanol electro-oxidation, indexed with the catalytic activity, stability of catalyst. As a result, it is found that the nanocomposite exhibits much higher activity and stability for methanol oxidation than the undoped Pt/CeO₂ catalyst.     

Tm-doped ZnO nanorods as a TCO for PV applications

In photovoltaic(PV) devices, a transparent conducting oxide(TCO) film is used as a transparent electrode which permits sun rays to reach to the photoactive semiconducting layers and also to collect the photogenerated electrons. Due to their electrical and optical properties zinc oxide(ZnO) based thin films and nanostructures are considered as an abundant and safer option for TCOs. In this study, undoped and thulium(Tm)-doped ZnO nanorods(NRs) were produced on glass substrates via spin coating and hydrothermal methods. The ZnO samples were described by X-ray diffractometry(XRD). Morphological features of the ZnO samples were investigated with scanning electron microscopy(SEM). It is observed that the all ZnO samples have nanorod shape. The average rods diameter is between 75 and 100 nm. Also,the rods length is found to be between 0.96 and 1.62 μm. Electrical properties of the ZnO samples were performed via four probe method. The conductivity increases with measurement temperature and Tm doping. Optical spectra of the ZnO samples were measured in UV-Vis range and the band gap(E_g) is found to be 3.35 eV.     

Synthesis and enhanced photoluminescence properties of red emitting divalent ion (Ca2+) doped Eu:Y2O3 nanophosphors for optoelectronic applications

This work presents the synthesis of Y₂O₃:Eu³⁺,xCa²⁺ (x = 0 mol%, 1 mol%, 3 mol%, 5 mol%, 7 mol%, 9 mol%, 11 mol%) nanophosphors with enhanced photoluminescence properties through a facile solution combustion method for optoelectronic, display, and lighting applications. The X-ray diffraction (XRD) patterns of the proposed nanophosphor reveal its structural properties and crystalline nature. The transmission electron microscope (TEM) results confirm the change in the shape of the particle and aggregation of particles after co-doping with Ca²⁺. Fourier transform infrared spectroscopy (FTIR) and Raman vibrations also confirm the presence of Y–O vibration and subsequently explain the crystalline nature, structural properties, and purity of the samples. All the synthesized nanophosphors samples emit intense red emission at 613 nm (⁵D₀→⁷F₂) under excitation with 235, 394 and 466 nm wavelengths of Eu³⁺ ions. The photoluminescence (PL) emission spectra excited with 235 nm illustrate the highest emission peak with two other emission peaks excited with 466 and 394 nm that is 1.4 times higher than 466 nm and 1.9 times enhanced by 394 nm wavelength, respectively. The emission intensity of Y₂O₃:Eu³⁺,xCa²⁺ (5 mol%) is increased 8-fold as compared to Eu:Y₂O₃. Doping with Ca²⁺ ions enhances the emission intensity of Eu:Y₂O₃ nanophosphors due to an increase in energy transfer in Ca²⁺→Eu³⁺ through asymmetry in the crystal field and by introduction of radiative defect centers through oxygen vacancies in the yttria matrix. It is also observed that the optical band gap and the lifetime of the ⁵D₀ level of Eu³⁺ ions in Y₂O₃:Eu³⁺,xCa²⁺ nanophosphor sample gets changed with a doping concentration of Ca²⁺ ions. Nanophosphor also reveals high thermal stability and quantum yield as estimating activation energy of 0.25 eV and 81%, respectively. CIE, CCT, and color purity values (>98%) show an improved red-emitting nanophosphor in the warm region of light, which makes this material superior with a specific potential application for UV-based white LEDs with security ink, display devices, and various other optoelectronics devices.     

Synthesis and characterization of Gd-doped PbMoO_4 nanoparticles used for UV-light-driven photocatalysis

Gd-doped PbMoO_4 nanoparticles were prepared by a refluxing method at 80℃ for 2 h.Effect of molar content of Gd dopant on phase,morphology and optical properties was studied.The as-prepared Gddoped PbMoO_4 samples can be indexed to pure tetragonal PbMoO_4 phase.The particles size of PbMoO_4 is decreased with increasing in the molar content of Gd dopant from 15.20±3.04 nm for pure PbMoO_4 to 8.72±1.53 nm for 5 mol% Gd-doped PbMoO_4.The absorption of 5 mol% Gd-doped PbMoO_4 nanoparticles shows red-shift caused by lattice distortion of PbMoO_4.The photocatalytic performance of 5 mol% Gddoped PbMoO_4 nanoparticles shows the highest degradation of rhodamine B(RhB) of 97.92% under UV radiation and 67.65% under visible radiation because Gd~(3+) dopant as an electron acceptor plays the role in enhancing the separation of electron-hole pair.     

A stable and efficient La-doped MIL-53(Al)/ZnO photocatalyst for sulfamethazine degradation

Photocatalytic technology can solve various environmental pollution problems, especially antibiotic pollution. A novel La-doped MIL-53(Al)/ZnO composite material was successfully synthesized by a combination of hydrothermal method and calcination, showing high photocatalytic degradation percent of sulfamethazine (SMT). The 2 mol% La MIL-53(Al)/ZnO photocatalyst shows the highest degradation efficiency toward SMT (92%) within 120 min, which is 4.1 times higher than pure ZnO (increased from 18% to 92%). In addition, the degradation analysis of SMT by high performance liquid chromatography proves that the products are CO₂ and H₂O. The improved photocatalytic activity is mostly caused by the following factors. (1) Doping La ions can decrease the band gap of ZnO, enhance light response, and effectively enhance the separation rate of photo-generated holes and electrons. (2) MIL-53(Al) can adsorb SMT and promote the separation of electron. This work shows that the synthesized La-doped MIL-53(Al)/ZnO photocatalyst is expected to be used as a green and effective method for treatment of environment water pollution.     

Synthesis of ZnO：Dy Nanopowder and Photoluminescence of Dy^3＋ in ZnO

A type of dysprosium-doped ZnO （ZnO：Dy） nanopowder was synthesized by high temperature calcinations. XRD was used to analyze the structure. Photoluminescence spectra were used to study the optical characteristic. PL of ZnO：Dy shows two different spectra which are broad band resulted from the defect of Dy in ZnO and sharp lines from the 4f→4f transition of isolated Dy^3 ＋ luminescence center. The emission and excitation spectra depend on the excitation wavelength and the concentration of Dy^3＋ . The broad bands with peaks at 600 and 760 nm are attributed to the recombination from an electron of the defect Dy in ZnO to a hole in VB.     

Synthesis of NaYF4:Nd@NaLuF4@SiO2@PS colloids for fluorescence imaging in the second biological window

Nd doped nanoparticles is commonly used as bioimaging agents but presents poor stability. Here, a polymer coating is applied to NaYF4:Nd nanoparticles using a versatile step-by-step coating strategy. The as-synthesized NaYF_4:Nd@NaLuF_4@SiO_2@PS colloids show good stability in various polar solvent and are very stable in water at least for 6 months. These NaYF_4:Nd@NaLuF_4@SiO_2@PS colloids can exhibit strong down converting photoluminescence when excited by 808 nm lasers. Moreover, these NaYF_4:Nd@NaLuF_4@SiO_2@PS colloids accumulate in liver of mice when used as bio-imaging agents. which exhibit strong fluorescence luminescence in NIR Ⅱ window.     

A comparative study of hydrothermal aging effect on cerium and lanthanum doped Cu/SSZ-13 catalysts for NH_3-SCR

Ce-or La-doped Cu/SSZ-13 catalysts were prepared by a hydrothermal method and Cu,Ce or La ions were incorporated through stepwise ion exchange,The catalyst activity was measured for the ammonia selective catalytic reduction reaction.The structure and composition of catalyst were characterized by using X-ray diffraction,scanning electron microscopy,inductively coupled plasma mass spectrometry solid-state NMR,NH_3-TPD techniques,and the active components were examined by XPS and XANES.The results indicate that the Ce and La doping can both completely preserve the SCR activity of Cu/SSZ-13 above 300℃,but there is also a decrease of activity below 200℃.On the other hand,Ce doping is beneficial to the formation of framework aluminum,stabilizes molecular sieve framework and Cu active sites of Cu/SSZ-13,thereby improves the catalyst hydrothermal stability.But La doping will decrease the amount of framework aluminum and Cu active sites of Cu/SSZ-13 after hydrothermally aging,even destroy zeolite CHA structure.This is quite harmful to the catalyst hydrothermal stability.     

Tribological properties of nanometer cerium oxide as additives in lithium grease

This paper presents a comparative study of the influence of nanometer-CeO_2(nano-CeO_2) and temperature on tribological and lubricating properties of lithium grease. The morphology and structure of nanocrystals were characterized by means of transmission electron microscopy(TEM) and X-ray diffraction(XRD), respectively. Friction and wear tests were conducted on the friction and wear tester.Results show that the lithium grease with addition of nanometer-CeO_2 has much better friction-reducing and anti-wear performance than that of base grease. When the additive in grease is 0.6 wt%, the friction coefficient(COF) and wear scar diameter(WSD) decrease by 28% and 13% comparing with base grease,respectively. The base grease and grease with 0.6 wt% nanometer-CeO_2 both possess the lowest average COF and wear width at 50 ℃. The worn surface morphology after friction test was analyzed by scanning electron microscopy(SEM) and NANOVEA three-dimensional profilometer. Under the lubrication of the lithium grease containing 0.6 wt% nano-CeO_2. few shallow furrows can be observed on the quite smoothed surface and the WSD decreased. Moreover, It was found that the nano-CeO_2 has been incorporated into the surface protective and lubricious layer by energy dispersive spectrometer(EDS) analysis.     

High photocatalytic activity over starfish-like La-doped ZnO/SiO_2 photocatalyst for malachite green degradation under visible light

In this work,the unique starlike La-doped ZnO-SiO2 photocatalysts were constructed by an evaporation and calcination method and characterized in detail.UV-vis reflectance and DFT calculation confirm that the doping with La allows to obtain a decrease of band gap of ZnO/SiO_2,which enhances visible light absorbance and oxidizing ability.The photoluminescence intensity reduces greatly,indicating more effective separation of the photo generated carriers of La-doped ZnO-SiO2.Photocatalytic activities of Ladoped ZnO-SiO2 with different doping ratios under simulated visible light irradiation were evaluated with malachite green(MG) as a model pollutant.Under optimized conditions including solution pH of 8,15 mg/L of MG solution and 15 mg of catalyst dosage,0.2% La-ZnO-SiO2 exhibits the best catalytic activity in photodegradations of MG in water.The removal and mineralization efficiency of MG can reach 96.1%and 70.9% in 140 min,respectively.The as-prepared catalysts present superior stability and recyclability after four times reuse.Moreover,selective quenching experiments indicate that hydroxyl radical(·OH),hole(h~+) and superoxide radical(·O_2~-) are the main reactive species responsible for MG degradation.Possible mechanism for photocatalytic elimination of MG over La-doped ZnO/SiO_2 photocatalyst is finally proposed.     

Fabrication of wide temperature lanthanum and cerium doped Cu/TNU-9 catalyst with excellent NH3-SCR performance and outstanding SO2+H2O tolerance

The effects of La on the catalytic performance,SO₂ and H2O resistance of Cu-Ce/TNU-9 catalyst were studied in the selective catalytic reduction of NO_x via ammonia(NH₃-SCR).The results show that the La doped Ce-Cu/TNU-9(CCL/T9) catalyst exhibits better SCR performance than Ce-Cu/TNU-9(CC/T9) and Cu/TNU-9(C/T9) in the wide temperature window(200-450 ℃) due to La benefiting from enhancing Cu⁺+Ce⁴⁺?Cu²⁺-+Ce³⁺ to facilitate ...     

Synthesis and luminescent properties of BaGd2O4:Eu3+ phosphors with highly efficient red-emitting

The BaGd_(2-2 x)Eu_(2 x)O_4(BG, x = 0.01-0.09) phosphors were successfully synthesized via the sol-gel method,and BaY_(2-2 y)Eu_(2 y)O_4(BY, y = 0.005-0.07) phosphors were included for comparison. The pure phase BG phosphors with the ordered CaFe_2 O_4-type structure are obtained by annealing at 1300℃ for5 h. The phosphors with uniform particle size of 120 nm and good dispersion display typical Eu~(3+)emission with the strongest peak at 613 nm(~5 D_0→~7 F_2 transition of Eu3+) under optimal excitation band at 262 nm(CTB band). The presence of Gd~(3+) excitation bands on the PLE spectra monitoring the Eu3+emission directly proves an evidence of Gd~(3+)-Eu~(3+) energy transfer. Owing to the concentration quenching, the optimum content of Eu3+ addition is 5 at%(x = 0.05), and the quenching mechanism is determined to be the exchange reaction between Eu3+. All the BG samples have similar color coordinates and temperature of(0.64 ± 0.02, 0.36 ± 0.01) and 2000 ± 100 K,respectively. The lifetime value of BaGd_(1.9)Eu_(0.1)O_4 for 613 nm is fitted to be 2.19 ± 0.01 ms, and the Eu~(3+) concentration does not change the lifetime significantly. Owing to the Gd~(3+)-Eu~(3+) energy transfer, the luminescent intensity of the BaGd_(1.9)Eu_(0.1)O_4 phosphor is better than BY system. The BG system served as a new type of phosphor is expected to be widely used in lighting and display areas.     

Synthesis and photoluminescence properties of Er3+ and Dy3+ doped Na2NbAlO5 phosphors

A series of Ln³⁺ (Ln³⁺ = Er³⁺/Dy³⁺) ions doped Na₂NbAlO₅ (NNAO) phosphors were synthesized by solid-state method. The Er³⁺ and Dy³⁺ ions doped phosphors were characterized by XRD, photoluminescence (PL) and decay profiles. The Ln³⁺-doped samples are consistent with the pure NNAO phase which is analyzed by the X-ray diffraction result. The PL graphs show that the intensity of luminescence increases with the increasing doping concentrations up to their critical certain values and then decreases at higher concentrations due to the concentration quenching effect of Er³⁺/Dy³⁺ ions. The energy level diagrams containing the positions of 4f and 5d energy levels of Er³⁺ and Dy³⁺ ions have been established and studied. In addition, under the ultraviolet light, the prepared NNAO:xLn³⁺ (Ln³⁺ = Er³⁺/Dy³⁺) phosphors show the characteristic green (Er³⁺), cyan (Dy³⁺) emission, respectively. Under the excitation of 365 nm, the quantum efficiencies of NNAO:0.01Er³⁺ and NNAO:0.03Dy³⁺ phosphors are measured to be 61.7% and 72.2%, respectively. The obtained results indicate that the new NNAO:xLn³⁺ (Ln³⁺ = Er³⁺/Dy³⁺) phosphors are promising applications in white-light emitting diodes field.     

Effects of yttrium and phosphorus on growth and physiological characteristics of Microcystis aeruginosa

Yttrium is a main kind of rare earth elements (REEs) with wide applications in modern industry and farming. Phosphorus, an essential element of algae, is used as the nutrients and also one of the main factors of eutrophication. To investigate the effects of yttrium and phosphorus on Microcystis aeruginosa (M. aeruginosa), the growth and physiological changes were studied by lab cultured experiments. In the experiment, exogenous yttrium was tested by a concentration gradient (0.0, 0.1, 0.3, 0.5, 1.0 mg/L), meanwhile, phosphorus was tested by three concentrations (0.0, 0.02, 0.2 mg/L). The results show that the contents of chlorophyll a (chl-a) and soluble protein increase compared with the control and they have certain correlation with algal cells density. The growth status of algae is stimulated by initial yttrium concentration ≤0.3 and 0.2 mg/L phosphorus, while it is inhabited by 0.5 and 1.0 mg/L yttrium. Besides, the activity of superoxide dismutase (SOD) of algae increases with addition of yttrium dose (0–0.3 mg/L) when phosphorus dose is 0.2 mg/L. Furthermore, when yttrium dose is 0.5 and 1.0 mg/L, the vitality of SOD presents a sharp decline. The malondialdehyde (MDA) contents increase with time and addition of yttrium dose, 0.2 mg/L phosphorus weakens the accumulation of MDA.     

Role of cerium as a promoter and process optimization studies for dehydration of glycerol to acetol over copper chromite catalyst

Cerium-promoted silica supported copper chromite catalyst was synthesized from acid hydrolysis of sodium silicate by sol-gel method.The catalyst was characterized by Brunauer-Emmett-Teller(BET)method,field-emission scanning electron microscopy(FESEM),X-ray diffraction(XRD),H₂-temperature programmed reduction(H₂-TPR),NH3-temperature programmed desorption(NH3-TPD)and pyridine adsorbed Fourier transform infrared spectroscopy(Py-FTIR).Among cerium doped catalysts,5 wt%of Ce promoted copper chromite supported by 40 wt%of silica(SiCuCr40-Ce5)shows the largest BET surface area.XRD analysis of the reduced form of the catalyst shows both CeO₂/Ce₂O₃ redox system and CuO/Cu₂O/Cu redox system.Py-FTIR shows the maximum number of Lewis acid sites for SiCuCr40-Ce5 than others.The highest acetol selectivity with analytical reagent(AR)grade glycerol conversion is observed for SiCuCr40-Ce5 at 200℃for 3 h in a batch reactor at atmospheric pressure.Cerium promotion lowers the reaction te mperature with enhanced glycerol conve rsion and increased acetol selectivity.Though the above catalyst shows higher conversion for laboratory reagent(LR)grade glycerol but it reduces acetol selectivity.The addition of glucose into the LR grade glycerol further reduces glycerol conversion and decreases the acetol selectivity to zero.This may be due to the presence of iron as impurity in LR grade glycerol.XRD analysis of spent catalyst shows the absence of redox catalytic system and the pore volume reduces identified by BET analysis.Raman analysis of the spent catalyst shows graphite-like carbon deposition in the spent catalvst.     

Synthesis and characterization of Co_(1-2x)Ni_xMn_xCe_yFe_(2-y)O_4 nanoparticles

Spinel ferrite Co_(1-2 x)Ni_xMn_xFe_(2-y)Ce_yO_4(0.0≤x=y≤0.3) nanoparticles(NPs) were prepared by sol-gel auto-combustion method.The synthesized NPs were examined using several techniques such as X-ray diffraction(XRD),field emission scanning electron microscopy(FE-SEM) coupled with EDX and elemental mapping,transmission electron microscopy(TEM),Fourier-transform infrared spectroscopy(FT-IR),and a vibrating sample magnetometer(VSM).The analysis of the crystal structure and the phase identification of samples indicates the formation of spinel cubic phase with the occurrence of CeO_2 as secondary phase when the content of Ce substitution element increases.In addition,all produced samples exhibit cubic symmetry with space group Fd3m.TEM confirms the presence of two phases,i.e.,the cubic spinel ferrite and the cubic cerium oxide(CeO_2).The characteristics of hysteresis loops reveal the soft ferrimagnetic nature of the different synthesized samples.The saturation(M_s) and remanent(M_r) magnetizations fall on increasing the content of substituting elements.Compared with pure CoFe_2O_4 NPs,the value of coercive field(H_c) slightly increases for x=y=0.1 and x=y=0,2 NPs.Then,H_c reduces with further increasing the x and y contents.The squareness ratio is found to be in the 0.528-0.400 interval,indicating the single domain NPs with uniaxial anisotropy for the different produced NPs.The magneto crystalline anisotropy constant(K_(eff)),anisotropy field(H_a),magneton number(n_B) and the demagnetizing field(N) were also determined and discussed.     

Synthesis and photoluminescent properties of Sm~(3+)-activated La_3Si_6N_(11) as an orange-red emitting phosphor

A series of Sm³⁺-doped La₃Si₆N₁₁phosphor materials we re synthesized by a high temperature solid-state reaction method.The crystal structure,micro structure,photoluminescence properties,decay curves as well as thermal quenching properties of the as-prepared phosphors were investigated systematically.The excitation spectra contain a wide asymmetric band below 350 nm originating from the host absorption,several sharp excitation peaks in the range of 300-550 nm corresponding to f-f transition of Sm³⁺.Under the excitation of 369 and 414 nm light,the phosphors exhibit strong narrow-band orangered emission peaked at 605 nm.The average decay time of La_2.99Si₆N₁₁:0.01 Sm³⁺sample is fitted to be0.38 ms and the CIE coordinates were calculated to be(0.6105,0.3833).For water resistance,La₃Si₆N₁₁:Sm³⁺is better than K₂SiF₆:Mn⁴⁺phosphor.After soaking in deionized water for 300 min,the La₃Si₆N₁₁:Sm³⁺sample retains approximately 80%of its initial relative emission intensity.When the temperature rises to 423 K(150℃),the emission intensity of La_2.99Si₆N₁₁:0.01 Sm³⁺sample remains 85%in co mparison to that of room tempe rature.The activation energy was calculated to be 0.63253 eV,which is higher than those of Sm³⁺-activated oxide phosphors,indicating that the phosphor has relatively good thermal stability.     

Synthesis of Mg-based composite material with in-situ formed LaH3 and its hydrogen storage characteristics

In this work, a Mg-based composite material with in-situ formed LaH₃, Mg₂NiH₄-LiBH₄ + 20 wt% LaH₃, was prepared by ball milling LiBH₄ and hydrogenated LaMg₂Ni and Mg₂Ni powder mixture, followed by heat treatment at 573 K. The onset dehydrogenation temperature of the composite is reduced by 50 K compared with that of Mg₂NiH₄-LiBH₄. The LaH₃-doped composite shows faster kinetics, absorbing 1.43 wt% hydrogen within 100 s at 423 K, which is 6.5 times faster than Mg₂NiH₄-LiBH₄. Moreover, the composite releases 1.24 wt% hydrogen within 500 s at 573 K, 0.69 wt% higher than Mg₂NiH₄-LiBH₄. The activation energy of the composite is reduced by 8.2 and 80 kJ/mol compared with that of Mg₂NiH₄-LiBH₄ and commercial MgH₂, respectively. The improvement in hydrogen storage properties is attributed to the fact that LaH₃ promotes the generation of nano-sized spongy Mg structure, which has good catalytic activity during the subsequent hydrogenation/dehydrogenation process.