Hybrid Lead Halide Perovskites Research Articles

Perovskitizer Tuning Pb2+ 6s2 Lone Pair Effects in Hybrid Perovskite Halide Enables Multiaxial Self‐Powered X‐Ray Detection

AbstractThe stereochemical expression of the ns2 lone pair significantly impacts symmetry breaking and corresponding photoelectric properties. However, hindered by the symmetric octahedral configuration, the Pb2+ 6s2 lone pair in the well‐conductive lead halide hybrid perovskites (LHHP) are normally stereo‐inactive, new approaches to activate the 6s2 lone pair are still greatly desired. Herein, by exploiting a perovskitizer tuning Pb2+ lone pair method, the study successfully obtains a stereo‐active 6s2 in the polar perovskite PA2MHy2Pb3Br10 (PMPB, PA = n‐propylamine, MHy = methylhydrazine), and unprecedentedly performs a multiaxial self‐powered X‐ray detection. In detail, the stereo‐active 6s2 lone pair is caused by the coordination bond between the perovskitizer MHy and Pb atom. Emphatically, the N‐Pb bond induces a large angular distortion parameter (≈45 times larger than other LHHP) and the lowest‐symmetric space group (P1) crystallization. Therefore, PMPB natively contains multiaxial polarization, which acts as the driving force to separate and transport the X‐ray‐generated carriers, thus enabling multiaxial self‐powered X‐ray detection with a low detection limit (129 nGy s−1). This work reveals the relationship between stereo‐active lone pair and polarization and sheds light on future X‐ray detection.

Broadband Emission Induced by Band-Edge Carrier Reconfiguration in 2D Hybrid Lead Halide Perovskites.

Broadband emission in hybrid lead halide perovskites (LHPs) has gained significant attention due to its potential applications in optoelectronic devices. The origin of this broadband emission is primarily attributed to the interactions between electrons and phonons. Most investigations have focused on the impact of structural characteristics of LHPs on broadband emission, while neglecting the role of electronic mobility. In this work, the study investigates the electronic origins of broadband emission in a family of 2D LHPs. Through spectroscopic experiments and density functional theory calculations, the study unveils that the electronic states of the organic ligands with conjugate effect in LHPs can extend to the band edges. These band-edge carriers are no longer localized only within the inorganic layers, leading to electronic coupling with molecular states in the barrier and giving rise to additional interactions with phonon modes, thereby resulting in broadband emission. The high-pressure photoluminescence measurements and theoretical calculations reveal that hydrostatic pressure can induce the reconfiguration of band-edge states of charge carriers, leading to different types of band alignment and achieving macroscopic control of carrier dynamics. The findings can provide valuable guidance for targeted synthesis of LHPs with broadband emission and corresponding design of state-of-the-art optoelectronic devices.

Solution Processed Hybrid Lead Perovskite Films for White Light Emission and Lasing Applications

Abstract2D organic–inorganic hybrid lead halide perovskite films are fascinating optoelectronic materials for white‐light emission and lasing applications. Here, it is demonstrated that nano‐meter‐thick films of perovskites can be formed at room temperature using Langmuir–Schaefer (LS) deposition technique. In situ X‐ray measurements reveal a self‐assembly process of the 2D perovskite formation at the air–water interface. This formation process requires the presence of stearic acid monolayer on the water subphase having a solution of lead‐perovskite in dimethylformamide. Microscopy and X‐ray measurements of these nanofilms transferred onto substrates show crystalline phase formation that deviates from the known orthorhombic structure of the bulk crystals. The nanofilms exhibit novel broad optical emission with sharp band‐edge transition in temperature‐dependent photoluminescence studies. Also, their band‐edge emission is distinctly blue‐shifted compared to that of thicker 2D perovskite flakes prepared by the slow‐cooling chemical synthesis process. 2D flakes exhibit lasing that cannot be obtained in the LS nanofilms as their thicknesses are lower than the lasing wavelength prohibiting wave‐guide formation. The results show that the 2D single‐crystalline nature of the LS films and flakes are suitable materials to develop broad‐band white light emission across the entire visible range and to obtain lasing without external cavities, respectively.

Empowering Indoor Photovoltaics: Stable Lead‐Free Perovskites and Beyond

Indoor photovoltaics (IPVs) have garnered significant attention in recent years due to their potential to empower small portable electronic devices and the Internet of Things. After silicon solar cells, it is now widely acknowledged that the dominant technology in the field of outdoor photovoltaics/IPVs is hybrid lead (Pb) halide perovskites. Despite the fascinating characteristics of hybrid Pb halide perovskites, the presence of toxic Pb is regarded as one of the major factors that prevent commercialization. Low‐toxic, Pb‐free, and stable perovskites are also being used in outdoor solar cells (ODSCs), but their efficiencies are low due to large bandgap (i.e., ≈2.0 eV). Recently, some of the stable, Pb‐free perovskite materials have drawn great interest due to their initial performance across various fields, including light‐emitting diodes, photodetectors, X‐rays, photocatalysis, ODSCs, and in IPVs. In this perspective, the current status and prospects for Pb‐free halide perovskites, chalcogen perovskites, silver bismuth halide (AaBbXa + 3b) family, and other chalcogen materials are summarized and being explored to speed up the progress of IPVs.

Effect of film morphology on circular dichroism of low-dimensional chiral hybrid perovskites.

Chiral hybrid lead halide perovskites show interesting chiral optoelectronic properties. The extent of chirality is often estimated by their circular dichroism (CD) response. Here, we show that the CD data depend strongly on film morphology. Four of the six chiral hybrid lead halide films prepared, 2D (R- and S-MBA)2PbI4 and 1D (R- and S-MBA)PbI3 (MBA: methylbenzylammonium), form homogenous non-textured films and show an isotropic CD signal. In contrast, the other two samples, 1D (R- and S-MBA)PbBr3, form textured films, showing uncorrelated CD signals from different parts of the film. Therefore, the role of film morphology needs to be verified before designing and comparing the chiroptic and chiral optoelectronic properties of hybrid perovskites.

Modulation of optoelectronic properties in Cl and Br doped GUASnI[formula omitted] based perovskite solar cells: A Density Functional Theory analysis

Partial substitution of I by Cl or Br improves the performance of hybrid lead halide perovskite materials. Here, a systematic density functional theory (DFT)-based investigation has been carried out in some mixed halide perovskites having the general formula GUASnX3−yXy′, where GUA = guanidinium cation, X = iodine (I), X′ = chlorine (Cl) or bromine (Br), and y = 0, 1, 1.5, and 2. Results obtained have been compared with the pure iodine-based compound to understand the impact of doping ratio on physical, optoelectronic, and photovoltaic properties of the hybrid halide perovskite materials. From the analysis, it has been observed that all the designed compounds form thermodynamically stable three-dimensional perovskite structures. In addition, the designed compounds possess band gap (Eg) values within the range of 0.91-2.33 eV. However, Eg decreases with an increase in iodine content. Complex dielectric function and absorption coefficient analysis led to the conclusion that all the investigated compounds exhibit absorption maxima in the visible range of the electromagnetic spectrum. Moreover, photovoltaic performance analysis reveals that GUASnI3 exhibits the highest theoretical power conversion efficiency (PCE) of 27.78% among the studied compounds. The study also shows that the pure iodine-based compound is superior to the corresponding mixed halide compounds in terms of their optoelectronic and photovoltaic properties. Hence, it is expected that the study will provide researchers a basis to further investigate mixed halide perovskite based materials in the future.

Threshold bandgap of lead halide hybrid perovskites for making stable single crystal by NIR laser trapping

The remarkable optoelectronic properties of hybrid halide perovskites position them as pivotal materials for the next generation of electronic devices, LEDs, lasers, and solar cells, potentially revolutionizing these technological domains. In this study, we harness the capabilities of contemporary laser trapping technology—a non-contact method for manipulating particles—to elucidate the conditions necessary for stable perovskite crystal formation. Using a 1064 nm near-infrared (NIR) continuous-wave (CW) laser, commonly selected for trapping experiments, we establish the threshold bandgap essential for the stable crystallization of MAPbX3 perovskite crystals. Our research reveals that MAPbI3, with a bandgap of 1.59 eV, undergoes rapid explosive crystallization when subjected to the 1064 nm laser, making it unsuitable for stable crystal growth. In contrast, MAPbBr3 with a bandgap of 2.26 eV forms stable single crystals within 6 min at the air-solution interface, when exposed to the same 1064 nm NIR laser at 1.0 W output power. Notably, a minor reduction in bandgap to 2.23 eV in the mixed halide MAPbBr2.75I0.25 results in an abrupt transition to explosive crystallization. These findings introduce a novel insight into the bandgap dependency for the crystallization process, delineating a threshold bandgap of 2.26 eV for MAPbBr3, below which the crystal growth becomes unstable under a 1064 nm laser. The study provides a significant advancement in the field by defining the precise bandgap necessary for the formation of robust, stable perovskite crystals using laser trapping techniques. This threshold bandgap knowledge is crucial for developing controlled synthesis protocols for perovskites, optimizing their optoelectronic properties for application in modern technologies. Moreover, the investigation suggests that to achieve stable crystallization of perovskites with a bandgap below 2.26 eV, laser trapping with wavelengths longer than 1064 nm may be required, opening new avenues for material processing and device fabrication.

Fabrication of ambient processed carbon-based inorganic silver bismuth iodide solar cells without any expensive hole transport materials

Recently, tremendous progress has been made in inorganic–organic hybrid lead halide perovskite solar cells (PSCs). Still, most of the reported high-efficiency PSCs were made with harmful lead (Pb), which is one of the major obstacles to large-scale adoption. Silver bismuth iodide (AgBiI4) light absorbers have been identified as promising lead-free and low-toxic metal-halide materials for solar cell applications. Here, we present hole transport material (HTM) and lead-free carbon-based inorganic Rudorffite (AgBiI4) solar cells, which can be prepared by simple spin-coating using silver iodide and bismuth iodide precursors under ambient conditions. Powder X-ray diffraction (XRD), UV–visible absorption, and field emission scanning electron microscopy (FESEM) studies were used to characterize the deposited films. The performance of the fabricated device was studied using incident photon-to-current conversion efficiency (IPCE) and current density–voltage (J-V) characteristics. Electrochemical impedance spectroscopy (EIS) was used to investigate the charge transfer process at the interface of the fabricated device. Under standard illumination test conditions, the fabricated device showed a photoelectric conversion efficiency (PCE) of 1.04%. The devices also have good stability and retained 96% of their initial PCE after 200 hrs of storage in ambient conditions. This work demonstrates the potential of HTM-free, ambient processable, and lead-free Rudorffite stable solar cells.

The Impact of Ligand Removal on the Optoelectronic Properties of Inorganic and Hybrid Lead Halide Perovskite Nanocrystal Films

AbstractLigand exchange performed during or after the colloidal synthesis of nanocrystals (NCs) provides an efficient way to produce conductive NC solids for optoelectronics. Herein, a post‐synthetic ligand washing process is developed and applied to two different combinations of ligands and perovskite NCs, namely robust green CsPbBr3 NCs capped by didodecyldimethylammonium bromide and near‐infrared FAPbI3 NCs decorated by weakly bound oleic acid ligands. The impact of such processes on the morphological and optoelectronic NC properties is examined while exploring parameters such as the reaction time and the influence of oxygen and humidity. For the FAPbI3 NCs, ligand washing results in extended NC aggregation and substantial photoluminescence loss, with the treatment becoming more aggressive for air‐exposed films. For the CsPbBr3 NCs, the process is insensitive to the environmental conditions and results in partial ligand shell loss and NC close packing rather than bulk‐like aggregation while affecting less the optical properties. Upon ligand removal, the photoconductance increases by up to ≈90% and ≈60% for FAPbI3 NCs and CsPbBr3 NCs, respectively. THz spectroscopy produces qualitatively similar trends of the conductivity with ligand removal time, with THz mobility values as high as 30 and 6 V−1s−1cm2 for glove box prepared FAPbI3 and CsPbBr3 NCs, respectively.

Role of Hydrogen Bonding on the Design of New Hybrid Perovskites Unraveled by Machine Learning.

Selecting a set of reactants to accurately design a new low dimensional hybrid perovskite could greatly accelerate the discovery of materials with great potential in photovoltaics, or solid-state lighting. However, this design is challenging as most hybrid metal halides are not perovskites and no feature is clearly associated to the structural characteristics of the inorganic metal halide network. This work first demonstrates that the organic molecules are key parameters to determine the structure type of the inorganic network (i.e., perovskite versus non-perovskite). Then, machine learning (ML) algorithms are used to identify the key features of the organic cations leading to the perovskite structure type. Using a large dataset of hybrid metal halides, this work extracts the organic molecules of all hybrid lead halide compounds, calculates 2756 molecular descriptors and fingerprints for each of these molecules, and are able to predict through ML techniques if a specific organic amine will lead to the perovskite type with an accuracy up to 88.65%. Descriptors related to hydrogen bonding are identified as important features. Thus, a simple but reliable design principle could be demonstrated: the presence of primary ammonium cation is the primary condition to prepare hybrid lead halide perovskites regardless of their dimensionalities.

Meltable Hybrid Antimony and Bismuth Iodide One-Dimensional Perovskites.

Hybrid lead-halide perovskites have been studied extensively for their promising optoelectronic properties and prospective applications, including photovoltaics, solid-state lighting, and radiation detection. Research into these materials has also been aided by the simple and low-temperature synthetic conditions involved in solution-state deposition/crystallization or melt-processing techniques. However, concern over lead toxicity has plagued the field since its infancy. One of the most promising routes to mitigating toxicity in hybrid perovskite materials is substituting isoelectronic Bi(III) for Pb(II). Various methods have been developed to allow pnictide-based systems to capture properties of the Pb(II) analogues, but the ability to melt extended hybrid pnictide-halide materials has not been investigated. In this work, we prepare a series of one-dimensional antimony- and bismuth-iodide hybrid materials employing tetramethylpiperazinium (TMPZ)-related cations. We observe, for the first time, the ability to melt extended hybrid pnictide-halide materials for both the Sb(III) and Bi(III) systems. Additionally, we find that Sb(III) analogues melt at lower temperatures and attribute this observation to structural changes induced by the increased stereochemical activity of the Sb(III) lone pair coupled with the reduction in effective dimensionality due to steric interactions with the organic cations. Finally, we demonstrate the ability to melt process phase pure thin films of (S-MeTMPZ)SbI5.

Prominent reverse saturable absorption of lead-free two-dimensional organic-inorganic hybrid double perovskites promoted by defects

Two-dimensional (2D) organic-inorganic hybrid perovskites have exhibited prominent reverse saturable absorption (RSA), yet their practical application is hindered by the lack of a defect-tolerance performance-enhancing strategy and lead-related toxicity. This study demonstrates that the realization of RSA via excited-state absorption is an effective strategy to achieve defect-promoted RSA in a series of lead-free 2D hybrid double perovskites (A4AgBiBr8), where A represents propylammonium (PA), butylammonium (BA), and hexylammonium (HA). Among these, the (PA)4AgBiBr8 shows the best performance. The nonlinear absorption coefficient of the solution-phase deposited thin film is as high as (2.0 ± 0.3) × 104 cm GW−1, a value that is competitive with those of most mechanically-exfoliated 2D hybrid lead halide perovskites and inorganic monolayer/few-layer 2D materials. Spectral characterization and density functional theory calculation demonstrate that Br vacancies in A4AgBiBr8 introduce abundant defect states, which act as intermediate states and enable efficient excited-state absorption. Consequently, a larger number of defect states results in a stronger RSA response.

Bright circularly polarized photoluminescence in chiral layered hybrid lead-halide perovskites.

Hybrid perovskite semiconductor materials are predicted to lock chirality into place and encode asymmetry into their electronic states, while softness of their crystal lattice accommodates lattice strain to maintain high crystal quality with low defect densities, necessary for high luminescence yields. We report photoluminescence quantum efficiencies as high as 39% and degrees of circularly polarized photoluminescence of up to 52%, at room temperature, in the chiral layered hybrid lead-halide perovskites (R/S/Rac)-3BrMBA2PbI4 [3BrMBA = 1-(3-bromphenyl)-ethylamine]. Using transient chiroptical spectroscopy, we explain the excellent photoluminescence yields from suppression of nonradiative loss channels and high rates of radiative recombination. We further find that photoexcitations show polarization lifetimes that exceed the time scales of radiative decays, which rationalize the high degrees of polarized luminescence. Our findings pave the way toward high-performance solution-processed photonic systems for chiroptical applications and chiral-spintronic logic at room temperature.

Introducing Ferroelasticity into 1D Hybrid Lead Halide Semiconductor by Halogen Substitution Strategy.

Organic-inorganic hybrid lead halide perovskites (OLHPs), represented by (CH3 NH3 )PbI3 , are one of the research focus due to their exceptional performance in optoelectronic applications, and ferroelastic domain walls are benign to their charge carrier transport that is confirmed recently. Among them, the 1DOLHPs feature better stability against desorption and moisture, but related 1D ones possessing ferroelasticity are rarely investigated and reported so far. In this work, the 1D ferroelastic semiconductor (N-iodomethyl-N-methyl-morpholinium)PbI3 ((IDMML)PbI3 ) is prepared successfully by introducing successively halogenate atoms from Cl, Br to I into the organic cation of the prototype (N,N-dimethylmorpholinium)PbI3 ((DMML)PbI3 ). Notably, (IDMML)PbI3 shows the narrow bandgap energy (≈2.34eV) according to the ultraviolet-visible absorption spectrum and the theoretical calculation, and possesses the evident photoconductive characteristic with the on/off ratio of current of ≈50 under the 405nm light irradiation. This work provides a new case for the ferroelastic OLHPs and will inspire intriguing research in the field of optoelectronic.

Chemistry in the Molten State: Opportunities for Designing and Tuning the Emission Properties of Halide Perovskites.

A series of monolayered lead halide hybrid perovskites (HO2C(CH2)n-1NH3)2PbX4, named (Cn)2PbX4 (n = 4-6, X = Cl, Br), exhibiting a low congruent melting temperature (Tm) (Tm = 130 °C for (C4)2PbBr4), high stability in the molten state, and whitish type emission, are reported. From the synthesis in the molten state, rare solid solutions of mixed organic cations (Cn1-xCn'x)2PbX4 (n, n' = 4-6; X = Cl, Br; 0 ≤ x ≤1) as well as solid solutions of mixed halides (Cn)2Pb(X1-yX'y)4 (n = 4-6; X, X' = Cl, Br; 0 ≤ y ≤1) have been prepared and characterized (thermal behavior, powder X-ray diffraction (PXRD), photoluminescence properties). The impact of substitutions is significant on the thermal properties, lowering the Tm down to 100 °C for (C4)2Pb(Br0.25Cl0.75)4. The emission properties are slightly tuned in the case of mixed organic cation systems, whereas modifications are more dramatic in the case of mixed halide systems, leading to emission properties through the entire visible region. These results illustrate the great opportunities offered by the congruent melting properties of halide perovskites allowing syntheses in the molten state.

Simulation and analysis of high-performance hole transport material SrZrS3-based perovskite solar cells with a theoretical efficiency approaching 26%

To process the toxicity and stability issues of hybrid lead halide perovskites, we suggest chalcogenide perovskites as an actual alternative family of material-based solar cells. Zr-based chalcogenides AZrS3 (A = Ba, Ca, or Sr) are the most studied family of chalcogenide perovskites for optoelectronic applications, thanks to their low cost, strong absorbency, and high PCE. A device simulation of SrZrS3 as an absorbing material solar cell, as well as a proposal of low-cost Hole Transport Materials HTMs (Cu2O, CuSCN, and NiOx), were achieved by using the software SCAPS-1D. The key parameters (thickness, doping concentration (NA), and temperature) for each configuration are varied to inspect their impact on the device’s performance. In the interest of replacing the highly expensive gold (Au) electrode, the functionality of the metal work function was also investigated. As a result, we have found that for SrZrS3, the optimized configuration is: Ni (metal back contact)/NiOx (HTM)/SrZrS3 (Absorber)/ZnO (ETM)/FTO, which delivered at 400 K: a PCE of 25.97%, a VOC of 1.18 V, a JSC of 26.13 mA/cm2 and an FF of 84.29%.

Bond Polarizability as a Probe of Local Crystal Fields in Hybrid Lead-Halide Perovskites.

A rotating organic cation and a dynamically disordered soft inorganic cage are the hallmark features of organic-inorganic lead-halide perovskites. Understanding the interplay between these two subsystems is a challenging problem, but it is this coupling that is widely conjectured to be responsible for the unique behavior of photocarriers in these materials. In this work, we use the fact that the polarizability of the organic cation strongly depends on the ambient electrostatic environment to put the molecule forward as a sensitive probe of the local crystal fields inside the lattice cell. We measure the average polarizability of the C/N-H bond stretching mode by means of infrared spectroscopy, which allows us to deduce the character of the motion of the cation molecule, find the magnitude of the local crystal field, and place an estimate on the strength of the hydrogen bond between the hydrogen and halide atoms. Our results pave the way for understanding electric fields in lead-halide perovskites using infrared bond spectroscopy.

High‐Performance and Stability of CsPbBr3/WSe2 Hybrid Photodetectors Functionalized Using Quaternary Ammonium Ligands

AbstractThe 2D–0D hybrid photodetector, with its special structure, high sensitivity, and wavelength tunability, is reported as a promising candidate system for optoelectronic devices. As research on hybrid lead halide perovskite quantum dots (PQDs) has progressed, PQDs with high photoluminescence (PL) quantum yield and excellent absorption properties are increasingly applied in optoelectronic devices; however, PQD stability remains one of the biggest limitations on device performance. Here, it is reported that the properties and stability of the hybrid photodetectors are improved by surface passivation using the quaternary ammonium ligand (didodecyldimethylammonium bromide, DDAB). The average carrier lifetime of DDAB treated CsPbBr3 PQDs (DDAB‐capped PQDs) is longer than that of pristine CsPbBr3 PQDs by 6.68–14.88 ns. It is confirmed that the durability against water is reduced by only 25.8% at PL intensity and is preserved for more than 16 h. A 2D–0D hybrid photodetector is then fabricated by deposition of DDAB‐capped PQDs on the WSe2 field‐effect transistor device for a high‐performance photodetector. The WSe2/DDAB‐capped PQD hybrid photodetector exhibits an enhanced responsivity of 1.4 × 103 A W−1 and an improved detectivity of 3.1 × 1013 Jones under 40.0 µW cm−2 of a 405 nm laser.

High-performance photodetectors based on two-dimensional perovskite crystals with alternating interlayer cations

Organic-inorganic halide perovskite, as a low-cost, solution-processable material with remarkable optoelectronic properties, is ideal candidate to fabricate high-performance photodetectors and is expected to significantly reduce device costs. Compared to the common Dion-Jacobson and Ruddlesden-Popper two-dimensional (2D) layered hybrid perovskite compounds, the perovskites with alternating cations in the interlayer (ACI) phase show higher crystal symmetry and narrower optical bandgaps, which exhibit great potential for excellent photodetection performance. Herein, we report a high-performance photodetector based on the 2D bilayered hybrid lead halide perovskite single crystal with the ACI phase (GAMA2Pb2I7; GA = C(NH2)3 and MA = CH3NH3). The single-crystal photodetector exhibits high photoresponsivity of 1.56, 2.54, and 2.60 A/W for incident light wavelengths of 405, 532, and 635 nm under 9.82 nW, respectively, together with the correspondingly high detectivity values of 1.86 × 1012, 3.04 × 1012, and 3.11 × 1012 Jones under the same operating conditions. Meanwhile, a high-resolution imaging sensor is built based on the GAMA2Pb2I7 single-crystal photodetector, confirming the high stability and photosensitivity of the imaging system. These results show that the 2D hybrid lead halide perovskites with alternating interlayer cations are promising for high-performance visible light photodetectors and imaging systems.

Mn Doping in Low-Dimensional Perovskites: A Switch for Controlling Dopant and Host Emission

The growth of solid-state photonics relies on the design of highly efficient devices with tunable photoluminescence (PL) based on thermally stable phosphors. In this study, a room-temperature, all-ambient synthesis of Mn-doped hybrid lead halide perovskite phosphors is presented. By applying temperature-dependent (4.2–300 K) steady-state and transient PL measurements, the photophysical pathways of the hybrid system were identified and the carrier recombination processes at play were defined. At higher Mn-doping concentrations (>4%), the excitonic white light host emission nearly disappears, and a bright Mn transition appears at ∼650 nm with a record PL quantum yield of ∼87.4%. The intense sensitized Mn luminescence results from rapid and efficient exciton-to-dopant energy transfer, as evidenced by time-gated and femtosecond fluorescence upconversion measurements. A millisecond PL decay time attributed to the Mn dopant and a microsecond PL decay time associated with the excitonic emission of the host were found, indicating energy and reverse energy transfer in the system. These findings provide unique insights into the chemical tailoring of the Mn-dopant emission by investigating the coupling between the host semiconductor and the dopant ion, a stepping stone toward the development of high-performance solid-state light-emitting diodes and scintillators.