Molecular precursor mediated synthesis of electrocatalytically active Bi 2 Se 3 nanostructures has been demonstrated with facile morphological tuning.

Chemically flexible A2B2O7 oxides are attractive candidates for designing structure-specific functional materials by judicious substitution. However, modulating functionality by substitution is governed by the solubility limits of the substituent. Present work reports an a typical 10 mol % solubility of Y3+ in La2Ti2O7(LTO:10Y), substantially lower than 60 mol %, anticipated by cationic radius ratio guidelines (rA/rB) for A2B2O7. Systematic experimental and theoretical investigations have been performed to justify this limited solubility. The solubility of Y3+ in La2Ti2O7 was verified by XRD at the bulk scale and via an Eu probe at the polyhedral level. Whereas XRD shows phase segregation beyond 10 mol % Y3+, the 0.5 mol % Eu3+-codoped LTO:10Y sample showed typical Eu3+ emissions, advocating structural homogeneity. However, the corresponding excitation spectrum revealed that insertion of Y3+ in LTO enhanced the energy transfer by the titanium-oxygen polyhedral network, [TiO6]8- → Eu3+. These observations were rationalized through density functional theory (DFT) calculations, which unveiled yttrium's preference for a low-coordination La site that substantially modifies adjacent TiO6 polyhedra and influences the energy transfer. Combined experimental and theoretical studies propose that yttrium's preference for a lower coordination number and a shorter/stronger metal-oxygen bond renders site selectivity and simultaneous regulation of the TiO6 network, limiting its solubility in La2Ti2O7. Thus, it provides supporting evidence for bonding-controlled substitution of yttrium in La2Ti2O7, rendering solubility lesser than that endorsed by radius ratio guidelines.

Owing to its interesting geometry and electronic structure, KMnF3 perovskite is positioned as a potential next-generation material and has garnered remarkable attention. In particular, its potential towards multimodal imaging (magnetic centre and exclusive red band emission centre) has made KMnF3-up-converted nanomaterials captivating. The present work reports a cationic commingling at the B-site of KMnF3 for exploring the possibility of multimodal imaging. A finely controlled synthesis of KMnF3:Er/Yb nanocubes is achieved using a microwave (MW)-assisted method in an ionic liquid (IL), followed by detailed characterization (XRD, FE-SEM, TEM, up-conversion measurements, and magnetic properties). By varying the Yb-Er concentrations, the optimum content of Yb/Er is established, which achieves intense and exclusive red emissions. These KMnF3:Er/Yb nanocubes not only exhibit single-band red emission but also simultaneously display room-temperature paramagnetic behaviour. As a next-stage improvisation, the use of Co2+ as a paramagnetic impurity at the B-site in KMnF3:Er/Yb nanocubes is explored, and the result reveals that the red emission decreases along with the appearance of room-temperature weak ferromagnetism. In summary, cationic commingling performed in KMnF3 will assist in the development of future multimodal imaging materials.

Water splitting for hydrogen production and reducing water pollution using solar light are part of the Sustainable Development Goals, which require highly active photocatalytic materials. The heterostructures have demonstrated remarkable photocatalytic advantages in visible light. Herein, we report microwave-assisted green synthesis of CuO/Cu2O nanoparticles using Tridax plant leaf extract. The synthesized nanoparticles were characterized by using PXRD, UV-DRS, Raman spectroscopy, XPS, PL, TRPL, FE-SEM, HR-TEM, BET, and photocurrent. The photocatalytic water splitting performance of CuO/Cu2O and CuO was measured under visible light (λ ≥ 420 nm) irradiation using methanol as a sacrificial reagent in DI water and natural seawater. The H2 evolution rates in DI water for CuO/Cu2O and CuO are 2043.21 and 970.09 μmol g-1 h-1 with apparent quantum efficiency (AQE) values of 5.60 and 2.66 %, respectively. In natural seawater, the H2 evolution rates are 2599.29 and 1370.54 μmol g-1 h-1 with AQE values of 7.12 and 3.75 %, respectively. The rate of H2 evolution slightly increased in natural seawater. Also, the degradation of the methylene blue dye was examined here, and the efficiency of CuO/Cu2O was determined to be 97 % under natural sunlight. Electrocatalytic H2 evolution was also studied here by using linear sweep voltammetry. Tafel slope values for CuO/Cu2O and CuO are 153 and 250 mV dec-1, respectively. The lowest Tafel value of CuO/Cu2O indicates a faster rate of reaction, thereby producing easier charge separation and lowering the electron-hole recombination due to the presence of surface defects, smaller particle size, enhanced crystallinity, and the synergistic effect between Cu2O and CuO.

Our combined high-pressure XRD, Raman spectroscopy and DFT calculations based studies on Y2Ge2O7 suggest a tendency of structural transformation from ambient tetragonal structure to a phase with higher coordination around Ge and Y cations. However, due to geometrical constraints and insufficient energy at ambient temperatures, the structure eventually ends up in a disordered form. In our XRD measurements, we observed diffraction peaks corresponding to pyrochlore phase at 13.6 GPa alongside ambient phase peaks which eventually broaden and show overall disordered phase like character at similar to 16 GPa. Raman spectroscopy suggest that the order-disorder transformation at similar to 16 GPa includes both ambient structure as well as pyrochlore like coordination around cations, though, there is no signature of breaking-up of long chains of the edge-shared polyhedron group proposed earlier for isomorphic compound Ho2Ge2O7. Based on our DFT calculations, we propose that both the crystalline pyrochlore and the disordered phase at high-pressures have fundamentally similar transformation mechanism. The tetragonal structure to disordered phase transformation is driven by the geometric constraints when Ge-O-Ge bridging angle attains critical value of similar to 127 degrees and non-bonded O-O distance approaches to similar to 3.05 & Aring;. The pressure-induced disordering of Y2Ge2O7 is partially reversible as all the peaks of ambient tetragonal phase reappear upon release of the pressure from similar to 24 GPa, the highest pressure achieved in our experiments. The Raman spectra of the released sample also confirm recovery of the ambient-phase coordination.

Designing molecular precursors for the controlled synthesis of functional nanomaterials holds immense promise for advancing sustainable energy technologies. Herein, we report the synthesis and structural characterization of an air-stable bismuth(III) complex, [(L)2BiCl2(μ-Cl)]2 (1), derived from 3-benzyl-1-methyl-(1H)-imidazole-2(3H)-selone (L). This complex serves as an efficient single-source molecular precursor (SSP) for the facile preparation of rhombohedral Bi2Se3 nanostructures under mild conditions. A plausible mechanism behind the facile decomposition of the molecular complex into Bi2Se3 materials has been discussed. Powder X-ray diffraction (PXRD), electron microscopy, and diffuse reflectance spectroscopy (DRS) confirm the phase purity, crystal structure, and optical properties of the nanomaterials. Notably, reaction conditions significantly influenced the morphology, yielding nanoplates under solventless decomposition and nanosheets under solvent-assisted thermolysis. These Bi2Se3 nanostructures exhibit optical bandgaps of ∼1.56 eV (nanoplates) and ∼1.60 eV (nanosheets), highlighting their potential in optoelectronic and catalytic applications. Notably, the Bi2Se3 nanoplates demonstrate excellent HER performance, achieving an overpotential of 372 mV at -10 mA cm-2, a Tafel slope of ∼62 mV dec-1, and robust stability over 2000 cycles and 18 hours of continuous operation. Density functional theory (DFT) calculations reveal surface charge heterogeneity at the exposed Bi2Se3 layers, which is expected to enhance the adsorption of polar species. This study highlights the significance of the molecular precursor strategy for controlled synthesis of efficient Bi2Se3-based electrocatalysts for sustainable hydrogen production in neutral aqueous environments.

Cisplatin analogue consisting of platinum(II) complexed with a cyclic selenide, trans 3,4-dihydroxy selenolane (DHSred) was synthesized. It was characterized by microanalyses, NMR (1H, 13C{1H}, 77Se{1H} and 195Pt{1H}), FT-IR, Raman and UV-Vis spectroscopy and its molecular structure was obtained by a single crystal X-ray diffraction analysis as cis-[PtCl2(DHSred)2].H2O. It was evaluated for existance of polymorphism by DSC analysis which revealed the absence of any polymorphism but it exists as a single isoform in a temperature range-25 to 80 degrees C. The cis-[PtCl2(DHSred)2].H2O was evaluated for its cytotoxicity against human cancer cell lines from skin (A431), breast (SKBR3), lung (A549) and brain (LN229) origin. It exhibited a significantly low cytotoxicity as compared with a standard aquated cisplatin as well as DHSred itself was found to be non-cytotoxic. This observation directed us to design a strategy of DHSred treatment after cisplatin chemotherapy to remove the excess of cisplatin accumulated in cells especially in renal system in order to ameliorate the severe side effects of cisplatin. To evaluate this, we have synthesized the cis-[Pt(NH3)2(DHSred)2]Cl2 complex in-situ by reacting aquated cisplatin with DHSred and this complex also exhibited very poor cytotoxicity as compared to cisplatin. It revealed, that the excess of highly toxic aquated cisplatin could be converted to a nontoxic cisplatin analogue i.e., cis-[Pt(NH3)2(DHSred)2]Cl2 which is anticipated to overcome the severe side effects, because of cisplatin accumulation. Additionally, the DFT calculations were performed to study geometrical and electronic structures to correlate these with the observed highly decreased cytotoxicity of cis-[PtCl2(DHSred)2].H2O and cis-[Pt (NH3)2(DHSred)2]Cl2 complexes in comparison with cisplatin.

Optoelectronics lies at the core of numerous technological devices. The growth of the optoelectronics field largely relies on functional phosphors in which multipolar interactions between the phosphor center and the activator/sensitizer play a profound role in determining the device efficiency. Though the robustness, tunable lattice, and dielectric nature of germanates render them as frontrunner host materials for optoelectronics, yet their potential as the host of an optically active center has been largely underexplored. The present work reports first-time exploration of a yttrium pyrogermanate system to host an efficient upconverting Yb3+-Er3+ couple with Bi3+, introduced as a supplementary codopant to tailor system polarity and performance. Meticulous analysis by different techniques established the formation of the tetragonal Y2Ge2O7 phase with a homogeneous distribution of the luminescent center (Er3+) and sensitizer (Yb3+, Bi3+). DFT calculations in conjunction with experimental optical parameters reveal that while inclusion of Bi3+ preserves the geometrical symmetry of the host lattice, concurrently it enhances polarity in the neighbourhood of Er3+ ions and overall ionicity of host. This facilitates stronger multipolar interactions between the luminescent center and sensitizers along with enhancment in the probability of different electronic transitions of Er3+. Detailed analysis of relative intensity ratios of the green emission of Er3+ ions indicated that Y2Ge2O7:Yb/Er and Bi3+ codoped Y2Ge2O7:Yb/Er are suitable for temperature sensing in the 300-400 K range. Notably, inclusion of Bi3+ in Y2Ge2O7:Yb/Er not only enhances near-infrared-induced visible upconversion of Er3+ but simultaneously it also opens up the window of UV-to-visible downconversion by additional sensitization. In summary, the polar nature and dual mode luminescence of the "Bi3+ incorporated Y2Ge2O7:Yb/Er phosphor" make it a promising candidate for phosphor converted light-emitting diode application and spectral conversion application for boosting solar cell efficiency.

Chemically flexible A2B2O7 oxides are attractive candidates for designing structure-specific functional materials by judicious substitution. However, modulating functionality by substitution is governed by the solubility limits of the substituent. Present work reports an a typical 10 mol % solubility of Y3+ in La2Ti2O7(LTO:10Y), substantially lower than 60 mol %, anticipated by cationic radius ratio guidelines (r A/r B) for A2B2O7. Systematic experimental and theoretical investigations have been performed to justify this limited solubility. The solubility of Y3+ in La2Ti2O7 was verified by XRD at the bulk scale and via an Eu probe at the polyhedral level. Whereas XRD shows phase segregation beyond 10 mol % Y3+, the 0.5 mol % Eu3+-codoped LTO:10Y sample showed typical Eu3+ emissions, advocating structural homogeneity. However, the corresponding excitation spectrum revealed that insertion of Y3+ in LTO enhanced the energy transfer by the titanium-oxygen polyhedral network, [TiO6]8- -> Eu3+. These observations were rationalized through density functional theory (DFT) calculations, which unveiled yttrium's preference for a low-coordination La site that substantially modifies adjacent TiO6 polyhedra and influences the energy transfer. Combined experimental and theoretical studies propose that yttrium's preference for a lower coordination number and a shorter/stronger metal-oxygen bond renders site selectivity and simultaneous regulation of the TiO6 network, limiting its solubility in La2Ti2O7. Thus, it provides supporting evidence for bonding-controlled substitution of yttrium in La2Ti2O7, rendering solubility lesser than that endorsed by radius ratio guidelines.

The correlation between local structure & stereochemical activity of Bi 3+ ions lone pairs has been observed. This correlation governs attrition of lanthanide ions from penta-coordinated Bi sites in bismuth gallate during conversion from nano to bulk.

Nickel selenides (NixSey) have become attractive electrode materials in the field of energy applications because of their distinct chemical and physical properties. Among them, Ni3Se4 has been scarcely explored as an electrode material for battery applications, despite having a channeled structure and excellent redox properties, probably due to its synthetic limitations. Thus, accessing this material in phase-pure form is highly desirable to fully uncover its potential as an electrode material. This report describes a straightforward and readily scalable soft chemical method using a single-source precursor to obtain monoclinic Ni3Se4 spherical nanoparticles and its composite with rGO: Ni3Se4@rGO (rGO: reduced graphene oxide). When employed as anodes for Li-ion batteries, both the cells deliver reasonably high initial discharge capacities. An enhancement in performance for Ni3Se4@rGO has been observed with a cyclability of 250 cycles and 311 mAh/g capacity retention with similar to 100% Coulombic efficiency. The superior performance of Ni3Se4@rGO has been attributed to its structural flexibility during lithiation/delithiation and rGO-induced regulation of leakage of ions into the electrolyte.

CsPbBr 3 perovskite nanocrystals have emerged as a promising material in the fields of photovoltaics, optics, electronics, sensing, catalysis, and so on. But the coexistence of a new layered material CsPb 2 Br 5 with CsPbBr 3 , specially during synthesis draws a significant attention in crystal phase engineering which eventually tunes the other important properties. Here, we demonstrated an ionic liquid (IL) assisted solvothermal synthesis to prepare phase tuned, luminescent, and photocatalytic CsPbBr 3 and CsPb 2 Br 5 nanocrystals. Selective tuning of size, morphology, band gap and most importantly crystal phase of perovskite is achieved by changing the alkyl side chain length, the H‐bonding, aromatic π‐stacking ability and concentration of the 1‐alkyl‐3‐methylimidazolium bromide ILs, [C n mim]Br ( n = 2, 4, 6, and 8), and so on. Along with band gap engineering; emission peaks are crystal phase dependent and can also be tuned from blue (470 nm) to green region (543 nm) for CsPbBr 3 nanocrystals. It is found that pure monoclinic shows the photoluminescence quantum yield (PLQY) of 36%. However, for pure tetragonal and mixed phases, PLQY are only 4.5% and 11% respectively. Last but not the least, photocatalytic activity of nanosized CsPbBr 3 is confirmed by studying the degradation of crystal violet (CV) dye even in the presence of visible light.

Halide double perovskites have been considered as the most competitive alternative of lead-based perovskite for various optoelectronic applications. With the aim of understanding the intricacies of electronic diversity in halide double perovskites, this work reports a comparative theoretical investigation of Cs2NaEuCl6 and Cs2NaBiCl6 using Density Functional Theory with the PBE and HSE06 functionals. In electronic structure, the distribution of states on the energy scale is found to vary with the functional, and the extent of variance is greater for Cs2NaEuCl6. In the case of Cs2NaEuCl6, Eu-4f states emerge as isolated states within the mid gap region, and the extent of isolation was found to be greater for the HSE06 functional. In contrast, Bi-6p states in Cs2NaBiCl6 have been found to significantly mingle with anion states. The isolation and mingling of Eu's and Bi's valence electrons, respectively, in the two HDPs, have been confirmed by B3LYP calculation on the corresponding molecular analogue under the LCAO-MO approach. Since the facets of perovskite are important for its chemical reactivity, the electron localization function has been plotted along the [010], [110] and [111] directions and a greater extent of localization of electrons around the anion is observed for Cs2NaEuCl6 in contrast to Cs2NaBiCl6.

Bimetallic clusters, as the name suggests, are known to act as bifunctional catalyst. Therefore, it is possible to tune the composition of the catalyst to achieve the best performance for a specific reaction. In the first part of this work, we explore the geometric and electronic structures of various Ag-Pt bimetallic clusters and find the right composition for ORR, one of the most sought-after reactions in the field of energy materials. We have considered Ag-Pt bimetallic clusters in both free and on Al2O3(0001) support. The results reveal that the equilibrium structures of the bimetallic AgnPtm (n+m <= 12 atoms) clusters are governed by a balance of competing interactions (Pt-Pt vs Ag-Pt vs cluster-support interactions). Whilst the isolated decamer cluster with 5:5 or 6:4 composition (Ag6Pt4 and Ag5Pt5) shows atomically segregated structures, Ag rich clusters (Ag9Pt1-3) prefer to form core-shell pattern where Pt forms the core surrounded by Ag atoms. In general, these clusters adopt pseudo-planar structure on alumina support following the surface template. Analysis of the electronic structure shows that Al2O3 surface induces significant broadening in the energy states of the bimetallic cluster, which in turn facilitates higher mixing between d-states of the Ag and Pt in the complex. Finally, the d-band centre descriptor model has been utilized to underscore the chemical reactivity of these bimetallic clusters. Remarkably, the Ag6Pt4@Al2O3 cluster with d-band centre at -2.68 eV is found to be in "just right" zone for ORR. This is further corroborated by the reduction (similar to 25 %) in oxidation reaction enthalpy of the Ag6Pt4@Al2O3 than standard Pt(111) catalytic surface.

CsPbBr3 nanomaterials have wide application in photovoltaic areas. Judicious doping of Ln(3+) ions in CsPbBr3 can enhance its capabilities as a spectral converter. In the present article, we hypothesized that the dopant has a pivotal role and can enhance the potential of CsPbBr3 beyond photovoltaic areas. Here, we have synthesized upconverting CsPbBr3:Er/Yb nanomaterials using an ionic liquid (IL)-assisted microwave (MW)-based method where 1-butyl 3-methyl imidazolium bromide ([C(4)mim]Br) IL was not only used as a templating agent but also a reaction partner. Green emission was observed from pure CsPbBr3 nanomaterials along with 78% photoluminescence quantum yield; however, when excited by 980 nm laser, green (545 nm) and intense red (654 nm) emissions were observed for CsPbBr3: Er3+/Yb3+ due to transitions of H-2(11/2) + S-4(3/2)-> I-4(15/2) and F-4(9/2)-> I-4(15/2), respectively; however, no up-conversion emission is noticed from the tetragonal CsPb2Br5:Er3+/Yb3+ analog. Up-conversion emission intensity increases with Yb3+ ion concentration and reaches a maximum for CsPbBr3: Er3+ (1%)/Yb3+ (20%). Furthermore, we have demonstrated the chemodynamic potential of CsPbBr3 against Pseudomonas bacteria using hydrogen peroxide. We found significant bacterial cell death as a function of dopants. The mechanistic insight suggests the role of Fenton-like reactions in generating singlet oxygen, causing bacterial cell death.

Functionalizing graphene and its derivative, or doping them with heteroatoms can significantly enhance their optoelectronic, photonic and bio-photonic properties; but controlled and tuneable functionalization of GO is still in their infancy. Herein, a series of functionalized graphene oxide (FGO) are synthesized solvothermally by using task specific ionic liquids (ILs) of varying alkyl chain length; 1-alkyl-3-methylimidazolium tetra fluoroborate, [Cnmim]BF4 (n = 2, 4 etc.). ILs are not only used as a solvent but also as source of fluoride ion for functionalization of GO. A drastic decrease in the oxygen containing functional groups of GO upon fluorination is evidenced by FTIR, Raman, XPS, EDX analysis and electrochemical study. Solid state 19F NMR spectroscopy indicates that, fluorination happens exclusively in edge positions, not on basal planes. Band gap of FGOs decreases along with increasing the chain length of ILs. Further, intense blue emission and high photocatalytic efficiency, using crystal violet as model dye are observed for all the FGOs under visible light. The tailored functionalization by varying alkyl chain length of IL has been rationalized by DFT calculations. It has been realized that owing to the ease of dissociation for [Cnmim]BF4 complexes with n >= 10; greater extent of fluorination/functionalization of GO has been observed. Elimination of a non-covalent interaction on increasing the alkyl chain length has been attributed for lower stability of higher chain length IL which in turn renders ease of dissociation. Easy yet controlled functionalization of GO using tuneable ILs can open a new direction in the environment friendly synthesis and applications.

Even though technological relevance for nuclear and oxide fuel cell application has persuaded a large number of investigations on the Y2Zr2O7 system, its local structure still remains ambiguous and debatable. While diffraction-based investigations claim a lack of local ordering, the MAS NMR and Raman spectroscopic investigations speculate the presence of local ordering. Besides, a correlation between the local and global structures of Y2Zr2O7 is also missing to date. Present work attempts to get deeper insights into the local structure of Y2Zr2O7 and correlate the local structure with global disordering. Complementary investigation using multiple strategies (XRD, RAMAN, electron microscopy, DFT calculations) revealed the presence of pyrochlore-like features in globally disordered Y2Zr2O7. Globally distributed "local probe ions" (Sn4+ by MAS NMR and Eu3+ by photoluminescence (PL)) were utilized for establishing the correlation between local and global structures. The 119Sn MAS NMR spectra possess the shoulder peak bearing chemical shift values, which are improbable under complete cationic randomization. The emission and decay profiles of the Eu3+ ion recommend positioning of few probe ions at the centrosymmetric site, which was further reinforced by crystal field splitting and lifetime values. Thus, both NMR and PL results reaffirm the existence of a pyrochlore-like atomic arrangement in predominantly defective fluorite Y2Zr2O7 phase. These discernible pyrochlore-like features have been envisaged to be emanating from unevenness in bond strength and ionicity/covalency of Y-O and Zr-O bonds. Cationic and anionic randomization energetically endorses global disordering, but the bonding disparity induces short-range ordering. It is believed that the presented findings will guide future research in regulating the physicochemical properties of Y2Zr2O7 for the target applications.

One of the most fundamental aspects of cluster science is to understand the structural evolution at the atomic scale. In this connection, here we report a comprehensive study of the atomic and electronic structures of (CuO)n clusters for n = 1 to 12 using DFT-based formalisms. Both the plane wave-based pseudo-potential approach and LCAO-MO-based method have been employed to obtain the ground state geometries of neutral, cation and anion copper oxide clusters. The results reveal that neutral copper oxide clusters favor a planar ring structure up to heptamer and from octamer onwards they adopt a three-dimensional motif with (CuO)9 and (CuO)12 forming a barrel-shaped layered structure. Detailed electronic structure analysis reveals that the transition of the atomic structure from 2D to 3D is guided by the energy balance of the Cu-O (d-p) and Cu-Cu (d-d) bonds. The removal of one electron from the cluster (cation) results in slightly stretched bonds while the addition of one electron (anion) showed compression in the overall geometries. The thermodynamic and electronic stability of these clusters has been analyzed by estimating their binding energy, ionization energy and electron affinity as a function of size. Remarkably, among these clusters, the octamer (CuO)8 and dodecamer (CuO)12 show higher binding energy and electron affinity (similar to 6.5 eV) with lower ionization energy (5.5-6.0 eV). This unique feature of the octamer and dodecamer indicates that they are very promising candidates for both oxidizing and reducing agents in different important chemical reactions. Ground state of CuO clusters (n = 1-7) are planar nano-ring structure while octamer onwards non-planar stacked structures are observed. Nonamer and dodecamer assumes nano-barrel structure upon stacking nano-ring in staggered fashion.

Based on chemical intuition, linear trends are anticipated in Eu3+ photoluminescence performance inside a pyrochlore matrix of the chemical twins, Hf and Zr, owing to probable geometrical and chemical similarity around the luminescent center. The present work reports the drastically fluctuating result of doping Eu3+ in nanocrystalline pyrochlore, La2Hf2-xZrxO7 (LHZO), matrix on composition variation; the variation is counter to the anticipation-based chemical brotherhood of Hf and Zr. Zirconium-enriched samples of LHZO improve asymmetry around Eu3+ ion leading to enhanced photoluminescence quantum yield (PLQY). The samples with compositions 0.7Hf and 1.3Zr depict the lowest non-radiative channels with the highest theoretically calculated PLQY of ∼71% and excellent thermal stability (∼91%). Synergistic experimental and theoretical analysis reveals that Eu does not unbiasedly occupy La-sites in the pyrochlore LHZO matrix towards chemical twins of Hf and Zr; rather, it energetically prefers to occupy Zr-rich vicinal sites. When the composition with Zr is in the low-medium range, Eu has a higher probability of occupying Zr-rich vicinal sites depicting higher lifetime and PLQY. When Zr-content goes beyond 70-80%, the other site occupancies start contributing leading to a reduction in both lifetime and quantum yield. This work paves a great strategy and provides a futuristic potential to utilize europium luminescence in separating chemically close Hf-Zr for various technological applications.