Application In Light-emitting Diodes Research Articles

Regulating the concentration quenching in Eu3+-activated Lu2W3O12 red-emitting phosphors through phase transition for white light-emitting diode and plant growth applications

Red emission is crucial for fabricating high-quality phosphor-converted light emitting-diode (LED) to satisfy its vivid applications. Herein, Lu2(1-x)W3O12:2xEu3+ (Lu2W3O12:2xEu3+) red-emitting phosphors were developed through sol-gel reaction method. Through adding Eu3+, phase transition, from orthorhombic to monoclinic phase, happened in studied samples. Excited at 394 nm, the resulting phosphors emitted intense red emission and their intensities can be manipulated via phase transition. Specifically, the phase transition can delay concentration quenching in resultant phosphors, of which the optimal state was realized at x = 0.7, resulting in enhanced luminescence properties. Besides, the color purity and thermal stability of prepared phosphors can also be improved by means of phase transition. Based on Judd-Ofelt theory, the local symmetric performances of Eu3+ in synthesized phosphors were analyzed via calculating the corresponding Ω2 values. Via using the designed phosphors as red-emitting components, different types of LED devices were packaged, i.e. red-emitting LED and white-LED. For red-emitting LEDs, their emission bands matched well with the absorption bands of plant pigments, allowing their applications in plant growth, which had been confirmed by rice growth experiments. Furthermore, the packaged white-LED can emit warm white light with high color rendering index and low correlated color temperature, which were slightly impacted by working current. Our finding revealed that phase transition was an efficient route to delay the concentration quenching effect and regulate the luminescence characterizations of Eu3+-activated phosphors.

What Matters for the Charge Transport of 2D Perovskites?

Compared to 3D perovskites, 2D perovskites exhibit excellent stability, structural diversity, and tunable bandgaps, making them highly promising for applications in solar cells, light-emitting diodes, and photodetectors. However, the trade-off for worse charge transport is a critical issue that needs to be addressed. This comprehensive review first discusses the structure of 3D and 2D metal halide perovskites, then summarizes the significant factors influencing charge transport in detail and provides a brief overview of the testing methods. Subsequently, various strategies to improve the charge transport are presented, including tuning A'-site organic spacer cations, A-site cations, B-site metal cations, and X-site halide ions. Finally, an outlook on the future development of improving the 2D perovskites' charge transport is discussed.

Elastic-Plastic Fully π-Conjugated Polymer with Excellent Energy Dissipation Capacity for Ultra-Deep-Blue Flexible Polymer Light-Emitting Diodes with CIEy = 0.04.

Emerging intrinsically flexible fully π-conjugated polymers (FπCPs) are a promising functional material for flexible optoelectronics, attributed to their potential interchain interpenetration and entanglement. However, the challenge remains in obtaining elastic-plastic FπCPs with intrinsic robust optoelectronic property and excellent long-term and cycling deformation stability simultaneously for applications in deep-blue flexible polymer light-emitting diodes (PLEDs). This study, demonstrates a series of elastic-plastic FπCPs (P1-P4) with an excellent energy dissipation capacity via side-chain internal plasticization for the ultra-deep-blue flexible PLEDs. First, the freestanding P1 film exhibited a maximum fracture strain of 34.6%. More interestingly, the elastic behavior is observed with a low strain (≤10%), and the stretched film with a high deformation (>10%) attributed to plastic processing revealed the robust capacity to realize energy absorption and release. The elastic-plastic P1 film exhibits outstanding ultra-deep-blue emission, with an efficiency of 56.38%. Subsequently, efficient PLEDs are fabricated with an ultra-deep-blue emission of CIE (0.16, 0.04) and a maximum external quantum efficiency of 1.73%. Finally, stable and efficient ultra-deep-blue electroluminescence are obtained from PLEDs based on stretchable films with different strains and cycling deformations, suggesting excellent elastic-plastic behavior and deformation stability for flexible electronics.

Machine learning-enabled discovery of multi-resonance TADF molecules: Unraveling PLQY predictions from molecular structures

Unlocking the potential of multi-resonance thermally activated delayed fluorescence (MR-TADF) molecules for advanced organic light-emitting diode applications requires an insightful understanding of the relationship between molecular structures and photoluminescence quantum yield (PLQY). Utilizing molecular descriptors as inputs for machine learning (ML) algorithms, further illuminated by SHapley Additive exPlanations (SHAP) to interpret the ML model outcomes, this method effectively connects molecular structures to PLQY, providing targeted guidance for molecular design. A vast molecular library is generated via variational autoencoders, allowing for a comprehensive exploration of molecular space beyond conventional chemical intuition. High-throughput virtual screening, combined with our PLQY-focused model and a secondary model for emission peak wavelength prediction, efficiently identify promising candidates with blue-emitting properties. The robustness of our predictions is substantiated through quantum chemistry calculations. The integrative methodology proposed in this work not only streamlines the discovery of MR-TADF molecules but also provides a replicable framework for the intelligent design of other optoelectronic materials.

Achieving zero-thermal quenching of Al2(WO4)3:Eu,Tb red phosphors with low thermal expansion for LEDs

Minimizing the emission loss with rising temperature is important to fundamental research and technological applications of phosphor-converted white light-emitting diodes (pc-WLEDs). Red phosphor materials are crucial for improving the illumination and backlit display quality of pc-WLEDs. In this work, non-hygroscopic Al2(WO4)3:0.05Eu3+,0.05 Tb3+ (AWO:0.05Eu,0.05 Tb) red phosphors with low positive thermal expansion are successfully developed to simultaneously achieve zero thermal quenching (ZTQ) and a highly efficient red emitting. Under the optimal 397 nm NUV light excitation, AWO:0.05Eu,0.05 Tb exhibited a strong red emission at 618 nm with a high color purity (CP) of 99.71 % and a high internal quantum efficiency (IQE) of 80.24 %. Furthermore, a warm pc-WLED device with suitable color coordinates (0.347, 0.317), high color rendering index (CRI = 90.2) and low color correlated temperature (CCT = 4737 K) was fabricated based on the as-prepared red phosphor AWO:0.05Eu,0.05 Tb. The findings suggest that the proposed phosphor holds significant promise as a red component for high-power warm pc-WLEDs, which may open up new ways for the exploration of high-performance lanthanide-activated red phosphors towards versatile applications.

First-Principles Study on the Optoelectronic and Mechanical Properties of Lead-Free Semiconductor Silicon Perovskites ASiBr3 (A = K, Rb, Cs)

We deployed density functional theory to assess the structural, electronic, elastic, and optical properties of ASiBr3 (A = K, Rb, and Cs). KSiBr3, RbSiBr3, and CsSiBr3 band structure profiles suggest they are semiconductors with direct band gaps of 0.34, 0.36, and 0.39 eV, respectively. The material’s dynamic stability is evidenced by the formation energies acquired negative values (−2.35, −2.18, and −2.08 for K, Rb, and Cs respectively). Mechanical characteristics and elastic constants measured suggest the compound’s mechanical stability and ductile character, which was assessed by calculating the Poissons ratio (>0.25) and Pugh’s ratio (>1.75). The research also explores optical properties, including the dielectric function, refractive index, reflectivity, optical conductivity, absorption coefficient, and extinction coefficient for the optical spectrum. The findings highlight possible applications for these materials in the semiconductor industry and modern electronic gadgets. The optical properties assessment reveals that these materials have strong optical absorption and conductivity, making these compounds the best prospects for usage in solar cells. CsSiBr3’s lower band gap renders it the superior choice for light-emitting diode (LED) and solar cell applications. Our findings may provide a complete understanding for experimentalists to pursue additional research leveraging applications in LEDs, photodetectors, or solar cells.

Single-phase Ca3Sc2Ge3O12: Tb3+, Eu3+ phosphors with tunable photoluminescence and temperature sensing properties

A set of germanate garnet phosphors containing Tb3+ and Eu3+ were adequately synthesized using the high-temperature solid-state technique. The structural properties, photoluminescence characteristics, fluorescence lifetimes, and temperature-sensing capabilities of the phosphors were thoroughly investigated. X-ray diffraction confirms the crystalline structure of the phosphors, while photoluminescence spectra reveal a colour shift attributed to the transfer of energy from Tb3+ to Eu3+ as the concentration of Eu3+ increases. The phosphors excited by UV light display a transition in colour from green to yellow, and subsequently to red, which can be used as a colour tunable phosphor in white light-emitting diode (w-LED) applications. As a novel temperature sensing material, the maximum relative sensitivity of Ca3Sc2Ge3O12: Tb3+, Eu3+ phosphor is 0.1044 K–1 (298 K), highlighting its potential for applications in temperature sensing.

Vacuum-Boosting Precise Synthetic Control of Highly Bright Solid-State Carbon Quantum Dots Enables Efficient Light Emitting Diodes.

Carbon quantum dots (C-dots) have emerged as efficient fluorescent materials for solid-state lighting devices. However, it is still a challenge to obtain highly bright solid-state C-dots because of the aggregation caused quenching. Compared to the encapsulation of as-prepared C-dots in matrices, one-step preparation of C-dots/matrix complex is a good method to obtain highly bright solid-state C-dots, which is still quite limited. Here, an efficient and controllable vacuum-boosting gradient heating approach is demonstrated for in situ synthesis of a stable and efficient C-dots/matrix complex. The addition of boric acid strongly bonded with urea, promoting the selectivity of the reaction between citric acid and urea. Benefiting from the high reaction selectivity and spatial-confinement growth of C-dots in porous matrices, in situ synthesize C-dots bonded can synthesized dominantly with a crosslinked octa-cyclic compound, biuret and cyanuric acid (triuret). The obtained C-dots/matrix complex exhibited bright green emission with a quantum yield as high as 90% and excellent thermal and photo stability. As a proof-of-concept, the as-prepared C-dots are used for the fabrication of white light-emitting diodes (LEDs) with a color rendering index of 84 and luminous efficiency of 88.14lm W-1, showing great potential for applications in LEDs.

Excited-State Engineering Enables Efficient Deep-Blue Light-Emitting Diodes Exhibiting BT.2020 Color Gamut.

Organic luminescent materials that exhibit thermally activated delayed fluorescence (TADF) can convert non-emissive triplet excitons into emissive singlet states through a reverse intersystem crossing (RISC) process. Therefore, they have tremendous potential for applications in organic light-emitting diodes (OLEDs). However, with the development of ultra-high definition 4K/8K display technologies, designing efficient deep-blue TADF materials to achieve the Commission Internationale de l'Éclairage (CIE) coordinates fulfilling BT.2020 remains a significant challenge. Here, an effective approach is proposed to design deep-blue TADF molecules based on hybrid long- and short-range charge-transfer by incorporation of multiple donor moieties into organoboron multiple resonance acceptors. The resulting TADF molecule exhibits deep-blue emission at 414nm with a full width at half maximum (FWHM) of 29nm, together with a thousand-fold increase in RISC rate. OLEDs based on the champion material achieve a record maximum external quantum efficiency (EQE) of 22.8% with CIE coordinates of (0.163, 0.046), approaching the coordinates of the BT.2020 blue standard. Moreover, TADF-assisted fluorescence devices employing the designed material as a sensitizer exhibit an exceptional EQE of 33.1%. This work thus provides a blueprint for future development of efficient deep-blue TADF emitters, representing an important milestone towards meeting the blue color gamut standard of BT.2020.

Phosphonic Chloride Assisted Fabrication of Highly Emissive Mixed Halide Perovskite Films in Ambient Air for Blue Light-Emitting Diodes.

Blue perovskite light-emitting diodes (LEDs) have emerged as promising candidates for full-color display and lighting applications. However, the fabrication of blue-emitting perovskite films typically requires an inert environment, leading to increased complexity and cost in the manufacturing process, which is undesirable for applications of perovskite LEDs. Herein, we report a strategy to fabricate bright blue-emitting perovskite films in ambient air by incorporating phosphonic chlorides in a perovskite precursor solution. We used two different phosphonic chlorides, diphenylphosphonic chloride (DPPC) and phenylphosphonic dichloride (PPDC), and comparatively studied their effects on the properties of perovskite films and the blue LEDs. It is found that PPDC possesses a stronger chlorination ability due to higher hydrolysis reactivity; meanwhile, it has a stronger interaction with the perovskite compared to DPPC, resulting in an improved film quality and enhanced blue emission with a photoluminescence quantum yield of 45%, which represents the record value for the air-processed blue perovskite films. Blue perovskite LEDs are fabricated, and the emission wavelengths are effectively tuned by controlling the concentration of phosphonic chlorides. Benefiting from the optimized perovskite films with reduced nonradiative recombination and promoted charge injection and transport, the PPDC-derived blue perovskite LEDs exhibit improved performance with an external quantum efficiency of 3.3% and 1.2% for the 490 and 480 nm emission wavelength, respectively.

Preparation and luminescence properties of polypyrrole-thiophene derivatives

Four kinds of polypyrrole-thiophene derivatives (PPy-Th) are prepared via solution polycondensation using pyrrole, 3-acylpyrrole, and 2-thenaldehyde as monomers. The structure, molecular weight, micromorphology, thermal degradation, ultraviolet-visible absorption, and luminescence performance of the derivatives are investigated by fourier transform infrared (FTIR), hydrogen nuclear magnetic resonance (1HNMR) spectroscopy, gel permeation chromatography (GPC), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), ultraviolet-visible (UV-Vis), and fluorescence spectra. FTIR and 1HNMR confirm that the derivatives have been successfully fabricated, and GPC indicates that the derivatives belong to oligomers with narrow molecular weight distribution. For acyl-substituted derivatives, the microstructures are mainly lamellar accumulation. Furthermore, under ultraviolet excitation, the derivatives can produce blue or green light emission, corresponding to the transitions of large π electrons in the conjugated structure of the molecular chains. Especially, the maximum emission wavelengths and Stokes shifts of the acyl-substituted derivatives are markedly larger than that of the non-acyl-substituted derivatives. The fluorescence quantum yield and band gap of the PVT are 4.46% and 2.01 eV, respectively. The fabricated PPy-Th can be used as luminescent materials in the development and application of polymer light-emitting diodes.

Synthesis, Characterization, and Applications of Carbon Dots for Determination of Pharmacological and Biological Samples: A Review.

Carbon dots (CDs) are a novel category of carbon-based nanomaterials characterized by their small size, often less than 10 nm. CDs physical, chemical, and optical properties can be tuned using one-pot assembly. Because of their non-toxicity, biocompatibility, chemical and physical responsiveness, photo- and chemical-bleaching resistance, and low cost, nanoparticles have become incredibly versatile. They find various applications in detecting inorganic substances, bio sensing, visualizing cells, studying biological processes in live cells, and aiding in medication delivery. Additionally, CDs exhibit versatility in electronics and energy storage, making them promising candidates for applications in solar cells, light-emitting diodes, and supercapacitors. CDs are more photo stable for hours than typical fluorescent semiconductor quantum dots. Before applying CDs, they must be characterized. Techniques such as UV-VIS spectroscopy, fluorescence spectrophotometry, FT-IR, TEM, XRD, Raman spectroscopy, and NMR are commonly used to assess their photophysical and structural properties. This article review explores the synthesis, characterization applications of CDs in analytical techniques for the determination of various analytes. The article provides a detailed analysis of the different methodologies used to make nanomaterials and devices for the characterization of CDs. It also discusses the challenges that arise when using CDs in analytical techniques for detecting different analytes. The focus of this review is on accurately determining pharmaceutical and biological samples using CDs as sensing probes.

Excited-State Dynamics of MAPbBr3: Coexistence of Excitons and Free Charge Carriers at Ultrafast Times.

Methylammonium lead tribromide perovskite (MAPbBr3) is an important material, for example, for light-emitting applications and tandem solar cells. The relevant photophysical properties are governed by a plethora of phenomena resulting from the complex and relatively poorly understood interplay of excitons and free charge carriers in the excited state. In this study, we combine transient spectroscopies in the visible and terahertz range to investigate the presence and evolution of excitons and free charge carriers at ultrafast times upon excitation at various photon energies and densities. For above- and resonant band-gap excitation, we find that free charges and excitons coexist and that both are mainly promptly generated within our 50-100 fs experimental time resolution. However, the exciton-to-free charge ratio increases upon decreasing the phonon energy toward resonant band gap excitation. The free charge signatures dominate the transient absorption response for above-band-gap excitation and low excitation densities, masking the excitonic features. With resonant band gap excitation and low excitation densities, we find that although the exciton density increases, free charges remain. We show evidence that the excitons localize into shallow trap and/or Urbach tail states to form localized excitons (within tens of picoseconds) that subsequently get detrapped. Using high excitation densities, we demonstrate that many-body interactions become pronounced and effects such as the Moss-Burstein shift, band gap renormalization, excitonic repulsion, and the formation of Mahan excitons are evident. The coexistence of excitons and free charges that we demonstrate here for photoexcited MAPbBr3 at ultrafast time scales confirms the high potential of the material for both light-emitting diode and tandem solar cell applications.

Preparation of PANI modified hollow microspheres and its application in anti-static buffer foam of OLED under-display

The polyaniline (PANI) modified hollow microspheres (HMs@PANI) was prepared by in-situ polymerization and then applied as both foaming agent and conductive fillers. The coating of PANI on the surface of hollow microspheres (HMs) was studied, and a dense conductive layer was obtained. Moreover, HMs@PANI was co-doped with acrylic acid and hydrochloric acid in order to improve the dispersion. Finally, the as-obtained HMs@PANI-CO was added into the polyacrylate matrix, then the multi-functional syntactic foam with both better anti-static property and buffer property was obtained. When the addition of HMs@PANI was 20 wt%, the surface resistivity of the foam reached 2.32×106 Ω. Furthermore, the better buffer property, lightweight, compression resistance, and thermal conductive property were also presented, which would be important in the practical application of organic light-emitting diode (OLED) under-display.

Meticulously designed red emission carbon dots as efficient and stable luminescent species for rapid latent fingerprint recognition and light emitting diodes

The preparation of carbon dots (CDs) emitting long wavelength has attracted more attentions due to their unique advantages in biological and optoelectronic fields, including the wide absorption, long PL lifetime and deep-tissue penetration. Herein, we prepare the nitrogen and sulfur co-doped red emission carbon dots (R-CDs) from the 2,4-diaminodiphenylamine (DDA) and thiourea via a solvothermal reaction, which exhibit reliable red emission at 613 nm and possess a high quantum yield (QY) of 34 %. Meanwhile, the structural analysis and theoretical calculation reveal that the sulfur doping from thiourea increases the nitrogen and oxygen content of CDs, leading to the red emission observed in R-CDs. Subsequently, we design an integrated fingerprints recognition system based on the R-CDs phosphors for the imaging of latent fingerprints (LFPs) and fast LFPs recognition, expanding the application of biometric identification and comparison technology based on fluorescence. Finally, we successfully apply the R-CDs into red and white light-emitting diodes, improving plant growth efficiency. As a result, this work provides a new in-depth insight of red emission CDs and expands the application in latent fingerprint recognition and light-emitting diodes.

Optical and photoluminescence properties of trivalent rare earth ions doped LiMgPO4

Trivalent rare-earth-activated luminescent materials have attracted a lot of attention due to their fascinating optical properties and broad range of applications. In this study, polycrystalline Sm and Eu-doped LiMgPO4 luminescent materials were synthesized using a solid-state reaction technique. The crystalline structures, morphological features, and optical characteristics of the synthesized materials were thoroughly investigated using x-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Field-Emission Scanning Electron Microscopy (FE-SEM) and UV–vis spectroscopy. The Rietveld refinement analysis confirmed the phase purity of synthesized phosphors. In addition, the strain induced owing to the incorporation of trivalent rare-earth ions and crystallite sizes of each synthesized material was estimated using the Williamsons-Hall (W-H) and modified Debye-Sherrer equations. The estimated results of the microstrain were reported to be 0.0010, 0.0023 and 0.0020. Subsequently, as a consequence of distinct peak profile options, the projected average crystallite size by both approaches was distinct. The UV–vis spectroscopy analysis reveals that Sm and Eu doped materials exhibit absorption bands around 402 nm and 396 nm and depicts the declining band gap values. The Photoluminescence (PL) spectra at 402 nm and 395 nm excitation wavelengths exhibited the distinctive emissions of both Sm3+ (4G5/2 → 6H7/2) and Eu3+ (5D0 → 7F2) ions emanating due to the intra-configurational f - f and 4 f − 4 f transitions. Finally, the CIE diagram explicitly demonstrates that the Sm and Eu-modified materials reveal their exceptional color purity. McCamy’s approach was used to determine various parameters of trivalent rare-earth doped materials. The correlated color temperature ( TCCT ) and their coordinates TCCT (ζ, β) was found to be 2287 K, 1900 K, 0.281, 0.632, and 0.302, 0.681 respectively. Temperature-dependent emission spectra exhibit excellent color and thermal stability at high temperatures. The obtained results in this study indicate that the synthesized luminescent materials can potentially be used in white light-emitting diode applications.

Multifunctional applications of organic light-emitting diodes and room temperature phosphorescence based on benzoyl-fluorene hybrid molecules

Organic light-emitting diodes (OLEDs) and room temperature phosphorescence (RTP) materials have attracted great interests for their wide application in lighting and other fields. How to efficiently utilize triplet excitons to achieve the multifunctionality of OLED and RTP simultaneously is a major challenge. Herein, two blue molecules, 3PCZFB and 3PCZBF were reported. Theoretical calculations indicate that both molecules possess hybrid localized charge transfer (HLCT) characteristic. More importantly, both can simultaneously obtain electro-fluorescence and RTP properties by multiple harvesting of triplet excitons with high spin-orbit coupling matrix element (SOCME). The introduction of benzoyl fluorene increased the contribution of the n-orbital, resulting in a high SOCME, which is beneficial to both high exciton utilization efficiency (EUE) and RTP. The non-doped OLED of 3PCZFB achieved maximum external quantum efficiency (EQEmax) of 4.9 % and EUE of 58.6 % at 459 nm. Besides, 0.1 % 3PCZFB and 3PCZBF doped in PMMA sheets achieve RTP efficiencies of 6.6 % at 524 nm and 25.9 % at 506 nm, as well as lifetimes of 379.8 ms and 204.8 ms. This is the first time Benzoyl fluorene-based molecules achieved dual-function applications in OLED and RTP by utilizing and recycling triplet excitons of T1.

The effect of Al3+ ions on the self-reduction process of Yb3+ to Yb2+ ions and optical properties of Nd3+/Ybn+ (n = 3, 2) co-doped transparent silicate glass-ceramics containing Ba2LaF7 nanocrystals and Ag nanoparticles

The effect of Al3+ ions in the AlF3 compound on the reduction process of Yb3+ to Yb2+ ions in SiO2–AlF3–BaF2–TiO2–LaF3 (SABTL) transparent silicate glass-ceramics was investigated. The valence states of the elements in the raw materials mixture existing in the transparent silicate glass-ceramics were determined using X-ray photoelectron spectroscopy (XPS) spectrum analysis. The transparent silicate glass-ceramics SABTL containing Ba2LaF7 nanocrystals and Silver (Ag) nanoparticles (AgNPs) were identified through X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM) image. With the increase of Al3+ ions molar concentration, the self-reduction process of Yb3+ to Yb2+ ions was enhanced and thus significantly affected the optical bandgaps and upconversion (UC)-, near-infrared (NIR)- emissions of Nd3+/Yb3+ co-doped in SABTL containing Ba2LaF7 nanocrystals and AgNPs under excitation of 980 nm laser diode (LD). The optimal molar concentration ratio between SiO2 and AlF3 compound was determined such that the NIR bandwidth flatness of Nd3+/Yb3+ co-doped in SABTL containing Ba2LaF7 nanocrystals in the wavelength range of 1000–1200 nm was the flattest. In addition, the CIE 1931 (x, y) color coordinates for UC- and visible (VIS)- emissions of Nd3+/Yb3+ co-doped SABTL-0.5Nd2Yb-xAg (x = 0, 2, 3, 4, and 5) glass-ceramics samples are also calculated and determined the color region for light-emitting diode (LED) application.

SM3+-Activated LiZnPO4 Phosphors: Synthesis, Characterization, and Their Luminescent Properties for White Light-Emitting Diode Applications

SM3+-Activated LiZnPO4 Phosphors: Synthesis, Characterization, and Their Luminescent Properties for White Light-Emitting Diode Applications

Non-monotonic thermal conductivity modulation in colloidal quantum dot superlattices via ligand engineering

Colloidal quantum dots (QDs), which consist of inorganic cores surrounded by soft organic ligands, can self-assemble into superlattices exhibiting long-range order. Their tunability, in terms of size, shape, and ligand properties, makes them promising for applications in solar cells, photodetectors, and light-emitting diodes. However, the complex interplay between ligand stiffness, QDs cores-ligands coupling strength, and its impact on QDs' morphology and thermal properties is not well understood. This work employs molecular dynamics simulations to investigate the possibility of modulating the thermal conductivity of QDs superlattices via ligand engineering. It is found that the structural stability of QDs superlattices depends significantly on the interaction strength between the QDs cores and ligands. At lower interaction strengths, the instability manifests itself in a random fusion of the QDs cores, while at intermediate strengths a stable simple cubic lattice structure is maintained. Higher interaction strengths lead to amorphization in the surface regions of QDs core. We observed a nonlinear trend in the thermal conductivity with varying QD-ligand interaction strengths due to competing factors: fusion of QDs cores at lower interaction strengths and increased crosslinking interaction among ligands at higher interaction strengths. The influence of ligand stiffness on thermal conductivity was found to be minimal. This study provides a deep insight into the role of ligand stiffness and interaction strength on structural dynamics and thermal transport in QDs superlattice and demonstrates the feasibility of engineering thermal transport in QDs superlattice via ligand engineering.