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At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Electroluminescence and Plasmon-Assisted Directional Photoluminescence from 2D HgTe Nanoplatelets

In the visible range, 2D nanoplatelets (NPLs) have brought significant benefits compared to their 0D counterpart with an inherently anisotropic emission, a narrower photoluminescence (PL) signal, and new degrees of freedom to design heterostructures. Compared to the properties of cadmium chalcogenide NPLs in the visible, similar research is still mostly lacking in the infrared, in spite of existing synthetic paths to obtain narrow band gap semiconductors in 2D colloidal form. Here, in this paper, we focus on 2D HgTe NPLs and show how their PL can be stabilized through the proper choice of surface chemistry. We then demonstrate two important steps toward bright infrared light emitting diodes (LEDs) which are (i) the coupling to a plasmonic grating to control the magnitude and spatial direction of the PL signal and (ii) the observation of electroluminescence at 1300 nm, which is near telecom wavelength.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Photoluminescence Switching in Quantum Dots Connected with Carboxylic Acid and Thiocarboxylic Acid End-Group Diarylethene Molecules

We contrast the switching of photoluminescence (PL) of PbS quantum dots (QDs) cross-linked with photochromic diarylethene molecules with different end groups, 4,4′-(1-cyclopentene-1,2-diyl)bis[5-methyl-2-thiophenecarboxylic acid] ( 1C ) and 4,4′-(1-cyclopentene-1,2-diyl)bis[5-methyl-2-thiophenethiocarboxylic acid] ( 2T ). Our results show that the QDs cross-linked with the carboxylic acid end group molecules ( 1C ) exhibit a greater amount of switching in photoluminescence intensity compared to QDs cross-linked with the thiocarboxylic acid end group ( 2T ). We also demonstrate that regardless of the molecule used, greater switching amounts are observed for smaller quantum dots. Varying these parameters allows for the fabrication of photoswitches with tunable PL change. We relate these observations to the differences in the HOMO energy levels between the QDs and the photochromic molecules. Our findings demonstrate how the size of the QDs and the energy levels of the linker ligands influences the charge tunneling rate and thus the PL switching performance in tunneling-based photoswitches.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Strain-Modulated Exciton Localization and Enhanced Emission in Multilayer GaSe

Strain engineering is one of the most effective routes for tuning the electrical and optical properties of two-dimensional layered materials. Besides reproducing the results of other groups on the tunability and photoluminescence (PL) enhancement of free and bound excitons under mechanical deformation or thermal effects, we systematically studied the mechanical strain (wrinkle) and local thermal strain (laser heating) effects on the PL lifetime and polarization in GaSe multilayers and their interplay, revealing their coupled impact on excitonic dynamics. Here, the PL intensity of localized excitons in the wrinkle region of GaSe increases superlinearly with the excitation laser power. The polarization effect has been observed for the bound exciton in GaSe under mechanical strain, but not in GaSe under thermal strain. Fluorescence lifetime imaging (FLIM) measurements reveal strain-tunable lifetimes for both free and bound excitons, and the lifetime of the bound exciton is longer than the free exciton in the mechanical strain region, correlating with the enhanced emission of the bound exciton. These results highlight previously uncharacterized optoelectronic tunability in GaSe and broaden the design space for strain (or thermally)-controlled 2D layered devices.

, GaSe, Exciton localization↗
DOE OSTI2020

Strongly Coupled Exciton–Surface Lattice Resonances Engineer Long-Range Energy Propagation

Achieving propagation lengths in hybrid plasmonic systems beyond typical values of tens of micrometers is important for quantum plasmonics applications. Iin this paper, we report long-range optical energy propagation due to excitons in semiconductor quantum dots (SQDs) being strongly coupled to surface lattice resonance (SLRs) in silver nanoparticle arrays. Photoluminescence (PL) measurements provide evidence of an exciton-SLR (ESLR) mode extending at least 600 mu m from the excitation region. We also observe additional energy propagation with range well beyond the ESLR mode and with dependency on the coupling strength, g, between SQDs and SLR. Cavity quantum electrodynamics calculations capture the nature of the PL spectra for consistent g values, while coupled dipole calculations show a SQD number-dependent electric field decay profile consistent with the experimental spatial PL profile. Our results suggest an exciting direction wherein SLRs mediate long-range interactions between SQDs, having possible applications in optoelectronics, sensing, and quantum information science.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2024

Exploitation of Pore Structure for Increased CO 2 Selectivity in Type 3 Porous Liquids

CO 2 capture requires materials with high adsorption selectivity and an industrial ease of implementation. To address these needs, a new class of porous materials was recently developed that combines the fluidity of solvents with the porosity of solids. Type 3 porous liquids (PLs) composed of solvents and metal–organic frameworks (MOFs) offer a promising alternative to current liquid carbon capture methods due to the inherent tunability of the nanoporous MOFs. However, the effects of MOF structural features and solvent properties on CO 2 –MOF interactions within PLs are not well understood. Herein experimental and computational data of CO 2 gas adsorption isotherms were used to elucidate both solvent and pore structure influences on ZIF-based PLs. The roles of the pore structure including solvent size exclusion, structural environment, and MOF porosity on PL CO 2 uptake were examined. A comparison of the pore structure and pore aperture was performed using ZIF-8, ZIF-L, and amorphous-ZIF-8. Adsorption experiments here have verified our previously proposed solvent size design principle for ZIF-based PLs (1.8× ZIF pore aperture). Furthermore, the CO 2 adsorption isotherms of the ZIF-based PLs indicated that judicious selection of the pore environment allows for an increase in CO 2 selectivity greater than expected from the individual PL components or their combination. This nonlinear increase in the CO 2 selectivity is an emergent behavior resulting from the complex mixture of components specific to the ZIF-L + 2'-hydroxyacetophenone-based PL.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

Gold-Induced Chemical Perturbations in CdTe-Based Photovoltaic Cells

Back-contacting p-type CdTe has been identified as one of the major areas of loss in CdTe photovoltaic (PV) power conversion efficiency (PCE). In research settings, Au is a common contact material due to its ease of use and decent performance. This work provides a detailed investigation into using gold for back contacting As-doped, CdCl 2 -treated, polycrystalline CdTe that has been exposed to air after absorber processing, another routine practice. First, X-ray photoemission spectroscopy (XPS) is used to determine the native oxide to be 1.6 nm of CdTeO 3 by using a combination of angle-resolved XPS and the cadmium-modified Auger parameter. During gold metallization of CdTe, oxygen and oxidized tellurium are eliminated from the thin CdTeO 3 native oxide. The fates of the released oxygen and possibly cadmium and tellurium are not known, but these reaction byproducts can enter the absorber bulk or grain boundaries, stay at the interface, or dissolve in the Au. Interfacial hole barriers between CdTe and Au are measured for samples with and without the native oxide present prior to metallization. Results show that the thin CdTeO 3 alleviates the downward band bending by 40 meV from 470 to 430 meV even though it is consumed during interface formation. The implications of these chemical reactions on the device are assessed through photoluminescence (PL) spectroscopy, which shows losses in internal open circuit voltage (iVoc) from 820 to 795 meV, carrier lifetime from 123 to 45 ns, and PL quantum yield from 2.9 × 10 −5 to 1.2 × 10 −5 . Modeling timeresolved PL lifetimes demonstrates the back surface recombination velocity due to metallization reduces minority carrier lifetimes. These results identify the native oxide and show that it plays an important role in mediating downward band bending along with how the back interface reaction can negatively impact device-scale parameters and reduce PV PCE.

14 SOLAR ENERGY↗
DOE OSTI2024

Thermal-Strain-Enabled Enhanced Emission from UV Laser-Induced Defect Levels near the Surface of Multilayer MoS 2

Monolayer two-dimensional (2D) materials have been intensively studied while research on multilayers is still in its infancy. Here, we induce defects inside bulk MoS 2 through thermal annealing and near the surface of multilayer MoS 2 using 375 nm laser irradiation, and investigate their photoluminescence (PL) and fluorescence lifetime imaging (FLIM). Enhanced emission is limited within a certain MoS 2 thickness. The observed enhanced emission is evidenced by a threshold behavior in super-linear PL intensity increase, strong polarization effects, and increased lifetime of defect peak. The laser power threshold for enhanced emission is much smaller in defects near the surface than that inside the bulk of multilayer MoS 2 . The mechanical strain from a wrinkle of the sample further lowers the laser power threshold for enhanced emission. By exciting with a 639 nm laser that is close to the fundamental gap between the conduction band minimum and the valence band maximum, the lifetime of defect enhanced emission increased by 5 times. Furthermore, one of the competing indirect bandgap emissions disappears, and the defect emission peak dominates the PL spectrum in the wrinkle area with a strain. Furthermore, the discovered principle can be applied to future studies on the integration of enhanced emission and single photon emission involving selectively depopulating the conduction band of the host crystal to defect levels for quantum emitters.

2D materials↗
DOE OSTI2023

Enhanced Photostability of “Hollow” Mixed Halide Wide-Bandgap Perovskite Films

We investigated the role of hollow perovskite architectures in enhancing the photostability of mixed halide wide-bandgap perovskites. We focused on mitigating photoluminescence (PL) peak shifts caused by phase segregation when exposed to light. By analyzing the optical and structural properties of mixed bromide/iodide hollow perovskite thin films, we observed that the incorporation of hollow structures reduced the ionic conductivity in the films, leading to improved photostability compared to non-hollow perovskite samples. The mixed halide hollow perovskite thin films exhibited increased the bandgap. High-power laser irradiation was used to induce phase segregation, and changes in the PL emission spectra were measured as a function of irradiation time. The mixed halide hollow perovskite thin films exhibited reduced PL peak shifts compared to the control samples. The inclusion of enI 2 (en = ethylenediamine) resulted in a reduction in the overall ionic conductivity of the films and a lower trap density. Hollow perovskite films incorporated in solar cells indicated that while the initial efficiency of the solar cells decreased with increasing enI 2 concentration, the open-circuit voltage value increased, potentially due to the slight enhancement of the band gap. Furthermore, the findings highlight the potential of hollow perovskite architectures in enhancing the photostability of mixed halide perovskites

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

Quantification of Shallow Defect Suppression in Aminosilane-Passivated Lead Halide Perovskites via Optical and Electrochemical Methods

We combine fluence-dependent photoluminescence (PL) and electrochemical characterization to estimate defect-dependent trapping rates, energetic distributions, and densities of defects, in lead halide perovskite films Cs 0.1 FA 0.9 PbI 3 and Cs 0.17 FA 0.83 Pb­(I 0.75 Br 0.25 ) 3 , before and after trap passivation with vapor-deposited (3-aminopropyl)­trimethoxysilane (APTMS). For both compositions, the PL studies show that energetically shallow subgap near-valence defect densities lead to bimolecular nonradiative recombination which is reduced by 92% after APTMS treatment. Electrochemical characterization of these same active layers shows for the first time that APTMS passivation impacts mainly on near-valence (mobile anionic) defects that decrease in density by 4 orders of magnitude, from 10 18 cm –3 to 10 14 cm –3 , as a result of silane modification. Here, the combination of PL and electrochemical characterization promises a unique approach to speciation and quantification of a broader distribution of trap states in perovskites and provides straightforward assessments of the efficacy of defect mitigation strategies.

Defects↗
DOE OSTI2022

Porous Liquids as Electrolyte: A Case Study of Li + and Mg 2+ Ion Transport in Crown Ether-Based Type-II Porous Liquids

Here, we demonstrate crown ether (CE)-based type II porous liquid (PL) electrolytes in which CEs provide internal porosity and are capable of coordinating with Li + and Mg 2+ ions. We investigated the physicochemical properties of the PL electro-lytes with different functional groups and cavity sizes. Among the electrolytes studied, the 12-crown-4 (12C4)-based PL electrolyte exhibited the most enhanced ionic conductivity due to size match between the CE cavity and the Li + ion. Nu-clear magnetic resonance and Fourier transform infrared analyses revealed that addition of CEs reduces the Li + ion–solvent interaction, resulting in the formation of Li-CE complexes. The simulation study clearly showed that the solvated Li + and Mg 2+ ions form complexes with 12C4. The strategy described here using CE-based PLs should be applicable to the design versatile electrolytes for various metal-ion batteries.

Shin, Sun Hae Ra↗
DOE OSTI2020

Localized Excitons in NbSe 2 -MoSe 2 Heterostructures

Neutral and charged excitons (trions) in atomically thin materials offer important capabilities for photonics, from ultrafast photodetectors to highly efficient light-emitting diodes and lasers. Recent studies of van der Waals (vdW) heterostructures comprised of dissimilar monolayer materials have uncovered a wealth of optical phenomena that are predominantly governed by interlayer interactions. Here, we examine the optical properties in NbSe 2 -MoSe 2 vdW hetero- structures, which provide an important model system to study metal–semiconductor interfaces, a common element in optoelectronics. Through low-temperature photoluminescence (PL) microscopy, we discover a sharp emission feature, L1, that is localized at the NbSe 2 -capped regions of MoSe 2 . L1 is observed at energies below the commonly studied MoSe 2 excitons and trions and exhibits temperature- and power-dependent PL consistent with exciton localization in a confining potential. This PL feature is robust, observed in a variety of samples fabricated with different stacking geometries and cleaning procedures. Using first-principles calculations, we reveal that the confinement potential required for exciton localization naturally arises from the in-plane band bending due to the changes in the electron affinity between pristine MoSe 2 and NbSe 2 -MoSe 2 heterostructure. Here, we discuss the implications of our studies for atomically thin optoelectronics devices with atomically sharp interfaces and tunable electronic structures.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Emission Control from Transition Metal Dichalcogenide Monolayers by Aggregation-Induced Molecular Rotors

Organic–inorganic (O–I) heterostructures, consisting of atomically thin inorganic semiconductors and organic molecules, present synergistic and enhanced optoelectronic properties with a high tunability. Here, we develop a class of air-stable vertical O–I heterostructures comprising a monolayer of transition-metal dichalcogenides (TMDs), including WS 2 , WSe 2 , and MoSe 2 , on top of tetraphenylethylene (TPE) core-based aggregation-induced emission (AIE) molecular rotors. The created O–I heterostructures yields a photoluminescence (PL) enhancement of up to ~950%, ~500%, and ~330% in the top monolayer WS 2 , MoSe 2 , and WSe 2 as compared to PL in their pristine monolayers, respectively. The strong PL enhancement is mainly attributed to the efficient photogenerated carrier process in the AIE luminogens (courtesy of their restricted intermolecular motions in the solid state) and the charge-transfer process in the created type I O–I heterostructures. Moreover, we observe an improvement in photovoltaic properties of the TMDs in the heterostructures including the quasi-Fermi level splitting, minority carrier lifetime, and light absorption. Overall, this work presents an inspiring example of combining stable, highly luminescent AIE-based molecules, with rich photochemistry and versatile applications, with atomically thin inorganic semiconductors for multifunctional and efficient optoelectronic devices.

14 SOLAR ENERGY↗
DOE OSTI2020

PbS/CdS Quantum Dot Room-Temperature Single-Emitter Spectroscopy Reaches the Telecom O and S Bands via an Engineered Stability

We synthesized PbS/CdS core/shell quantum dots (QDs) to have functional single-emitter properties for room-temperature, solid-state operation in the telecom O and S bands. Two shell-growth methods–cation exchange and successive ionic layer adsorption and reaction (SILAR)–were employed to prepare QD heterostructures with shells of 2–16 monolayers. PbS/CdS QDs were sufficiently bright and stable to resolve photoluminescence (PL) spectra representing both bands from single nanocrystals using standard detection methods, and for a QD emitting in the O-band a second-order correlation function showed strong photon antibunching, important steps toward demonstrating the utility of lead chalcogenide QDs as single-photon emitters (SPEs). Irrespective of type, few telecom-SPEs exist that are capable of such room-temperature operation. Access to single-QD spectra enabled a direct assessment of spectral line width, which was ~70–90 meV compared to much broader ensemble spectra (~300 meV). We show inhomogeneous broadening results from dispersity in PbS core sizes that increases dramatically with extended cation exchange. Quantum yields (QYs) are negatively impacted at thick shells (>6 monolayers) and, especially, by SILAR-growth conditions. Time-resolved PL measurements revealed that, with SILAR, initially single-exponential PL-decays transition to biexponential, with opening of nonradiative carrier-recombination channels. Radiative decay times are, overall, longer for core/shell QDs compared to PbS cores, which we demonstrate can be partially attributed to some core/shell sizes occupying a quasi-type II electron–hole localization regime. Finally, we demonstrate that shell engineering and the use of lower laser-excitation powers can afford significantly suppressed blinking and photobleaching. However, dependence on shell thickness comes at a cost of less-than-optimal brightness, with implications for both materials and experimental design

36 MATERIALS SCIENCE↗
DOE OSTI2020

Spatially Resolved Persistent Photoconductivity in MoS2–WS2 Lateral Heterostructures

The optical and electronic properties of 2D semiconductors are intrinsically linked via the strong interactions between optically excited bound species and free carriers. Here we use near-field scanning microwave microscopy (SMM) to image spatial variations in photoconductivity in MoS 2 –WS 2 lateral multijunction heterostructures using photon energy-resolved narrowband illumination. We find that the onset of photoconductivity in individual domains corresponds to the optical absorption onset, confirming that the tightly bound excitons in transition metal dichalcogenides can nonetheless dissociate into free carriers. These photogenerated carriers are most likely n-type and are seen to persist for up to days. Informed by finite element modeling we reveal that they can increase the carrier density by up to 200 times. This persistent photoconductivity appears to be dominated by contributions from the multilayer MoS 2 domains, and we attribute the flake-wide response in part to charge transfer across the heterointerface. Spatial correlation of our SMM imaging with photoluminescence (PL) mapping confirms the strong link between PL peak emission photon energy, PL intensity, and the local accumulated charge. This work reveals the spatially and temporally complex optoelectronic response of these systems and cautions that properties measured during or after illumination may not reflect the true dark state of these materials but rather a metastable charged state.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Dual Emission Bands of a 2D Perovskite Single Crystal with Charge Transfer State Characteristics

Several hybrid halide 2D-perovskite species emit light with an emergent and controversial broadband emission Stokes-shifted down from the narrow band emission. This work uncovers the sub- and above-bandgap emission and absorption characteristics of PEA 2 PbI 4 prepared with gap states introduced during single crystal growth. Here, gap states led to coexistent intrinsic and heterostructured electronic frameworks that are selectively accessible with ultraviolet (UV) and infrared (IR) light, respectively, resulting in the phenomenon of photoluminescence (PL) switching from narrowband green to broadband red. Electron-energy dependent cathodoluminescence shows a relative increase in the broadband red PL intensity as the electron penetration depth increases from 30 nm to 2 μm, confirming the heterostructured framework is formed in the bulk of the crystal. Excitation–emission power slope of 2.5 and up-conversion pump transient absorption (TA) spectra suggest that the IR up-conversion excitation with red photoluminescence, peaked at 655 nm, is a multiphoton process occurring in the heterostructured framework through a nonlinear optical response. The energetic pathways toward the dual emission bands are revealed by pump–probe transient absorption spectroscopy, showing energetically broad gap states with high sensitivity to an IR pump are upconverted and subsequently quickly relax from high to low energy levels within 4 ps. Furthermore, the up-conversion red PL demonstrates a linear polarization with magnetic field effects, thus affirming that the band-like heterostructured framework is crystallographically aligned with characteristics of spatially extended charge-transfer states.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Dynamic Behavior of Bound Interlayer Excitons in Interlayer-Doped Cs 3 Bi 2 Br 9 Vacancy-Ordered Perovskite

Interlayer doping of the vacancy-ordered 2D perovskite Cs 3 Bi 2 Br 9 (CBB) enables the formation of bound interlayer excitons (BIEs), a unique charge-transfer excited state within the layered solid. BIEs previously reported with silver (Ag + ) as an interlayer dopant exhibited bright broadband photoluminescence (PL) with prolonged lifetime at room temperature, offering potential applications in efficient white light emission, photocatalysis, and optoelectronics. However, the dynamic behavior of radiation and excited carriers remains poorly understood due to the limitations of ensemble spectroscopic measurements. Here, we investigate the temperature-dependent dynamics of Ag-doped Cs 3 Bi 2 Br 9 (Ag-CBB) using single-particle time-resolved PL spectroscopy and ultrafast transient absorption imaging. Single-particle PL measurements reveal three distinct emission regimes across temperature: (i) BIE-dominant emission at high temperatures, (ii) a mixture of radiation from BIEs and self-trapped excitons (STEs) at intermediate temperatures, and (iii) STE-dominant emission below 100 K. Rapid transient absorption mapping using Parallel Rapid Imaging with Spectroscopic Mapping (PRISM) reveals subpicosecond STE formation in pristine CBB and long-lived photoinduced absorption by BIEs, consistent with electron–hole separation and suppressed STE transfer. The spatial uniformity of these signals confirms homogeneous Ag doping across single crystals. These findings highlight the role of Ag interlayer dopants in governing the BIE dynamics.

bound interlayer exciton↗
DOE OSTI2025

Single-Molecule Fluorescence Microscopy Reveals Energy Transfer Active versus Inactive Nanocrystal/Dye Conjugate Pairs

Defect-mediated energy transfer (EnT) is a radiative process that occurs between donor defect states in the forbidden bandgap of semiconductor nanocrystals (NCs) and dye molecules bound to their surfaces. The EnT efficiency depends on the number of dye molecules attached to each NC, the donor–acceptor distance, and the dipole orientation factor between the donor and acceptor, all of which vary across all individual NCs in a sample. While ensemble-level fluorescence spectroscopy measurements have provided average values for donor–acceptor distances, dye-to-NC ratios, and EnT rate constants, questions remain about the impact of donor/acceptor heterogeneity on observed EnT efficiencies. Notably, ensemble-level measurements cannot distinguish between bare NCs and EnT-active versus inactive NC/dye pairs in the same sample batch, limiting the ability to design systems with 100% EnT efficiency. To address this, we studied defect-mediated EnT between AlexaFluor 555 dye acceptors chemically bound to ZnO NC donors at the level of single molecules and single NCs. Interestingly, 20% of bound NC/dye pairs are EnT-inactive, likely contributing to residual defect photoluminescence (PL) observed in ensemble-level measurements and reducing overall EnT efficiency. Single particle-level ZnO defect PL and acceptor fluorescence trajectories exhibited distinct microfluctuations, which are absent in bare ZnO NCs. We hypothesized that our observations can be explained with a competitive dye fluorescence quenching pathway, possibly due to charge transfer between the excited state dye and the ZnO NC. Numerical simulations of single-molecule PL traces for this scenario produced microfluctuations consistent with the experimental results. These findings highlight the impact of sample heterogeneity on EnT processes and provide insights for designing light-harvesting systems with optimized EnT efficiency.

25 ENERGY STORAGE↗
DOE OSTI2021

Mechanistic Investigation of Molybdenum Disulfide Defect Photoluminescence Quenching by Adsorbed Metallophthalocyanines

Lattice defects play an important role in determining the optical and electrical properties of monolayer semiconductors such as MoS 2 . Although the structures of various defects in monolayer MoS 2 are well studied, little is known about the nature of the fluorescent defect species and their interaction with molecular adsorbates. In this study, the quenching of the low-temperature defect photoluminescence (PL) in MoS 2 is investigated following the deposition of metallophthalocyanines (MPcs). The quenching is found to significantly depend on the identity of the phthalocyanine metal, with the quenching efficiency decreasing in the order CoPc > CuPc > ZnPc, and almost no quenching by metal-free H 2 Pc is observed. Futher, time-correlated single photon counting (TCSPC) measurements corroborate the observed trend, indicating a decrease in the defect PL lifetime upon MPc adsorption, and the gate voltage-dependent PL reveals the suppression of the defect emission even at large Fermi level shifts. Density functional theory modeling argues that the MPc complexes stabilize dark negatively charged defects over luminescent neutral defects through an electrostatic local gating effect. These results demonstrate the control of defectbased excited-state decay pathways via molecular electronic structure tuning, which has broad implications for the design of mixeddimensional optoelectronic devices.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗