Optoelectronic Applications Research Articles

Interplay between Theory and Photophysical Characterization in Symmetric α-Substituted Thienyl BODIPY Molecule.

4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY)-based molecules have emerged as interesting materials for optoelectronic applications due to the possibility to easily fine-tune their photophysical and optical properties, dominated by two main absorption bands in the visible range. However, no studies have been reported on the nature of these spectral features. By means of ultrafast spectroscopy, we detect intramolecular energy transfer in a spin-coated film of di-thieno-phenyl BODIPY (DTPBDP) dispersed in a polystyrene matrix after pumping the high-energy absorption band. The same effect is not present upon pumping the lowest-energy band, which instead allows the achievement of efficient amplified spontaneous emission. Density functional calculations indicate the different nature of the two main absorption bands, explaining their different photophysical behavior.

An inclusive study of lead-free perovskite CsMI3 materials for photovoltaic and optoelectronic appliance explored by a first principles study

The prime objective of this study is to understand the lead-free CsMI3 (M = Pb, Mg, Ga, Ca, Ba, Sr) perovskites for photovoltaic and optoelectronic applications using first-principle calculations. This study considered the structural aspects along with the mechanical, electrical, optical, and thermal properties. The formation energy, phonon dispersion curve, and elastic constants were calculated to check the structural stability of the compounds. The computed Poisson ratios (ν) support the CsMI3 compounds' ductility; only the CsMgI3 compounds lie on the ductile-brittle transition line. However, the compounds' ductility is confirmed by the Cauchy pressure, which also reflects the materials' mechanism of mechanical failure. The band structure calculations confirmed the energy band gap, Eg, in the range of 1.63–3.26 eV, which makes them suitable for absorbing materials in solar cell applications. The optical properties calculations revealed strong photoconductivity, low reflectivity, and high absorption coefficient, all of which show photovoltaic properties given the materials use in the solar cell application. Among the titled compounds, CsMgI3 will be the best replacement of Pb-based perovskites for photovoltaic and optoelectronic appliances. The substitution of I by Br in the CsMgI3 causes a significant improvement (band gap is increased from 1.12 to 1.87 eV; absorption coefficient is also increased) in the photovoltaic properties. The Eg and α further increase due to doping into the CsMg(I1-xBrx)3 where x = (0.25) makes them apposite for solar cell materials. The best combination, CsMg(I0.75Br0.25)3, shows Eg ∼ 1.4 eV, which may be considered as the optimum band gap for the highest efficiency of a single solar cell according to the Shockley-Queisser limit.

Optimized poly(methyl methacrylate)/mixed‐phase silver vanadate nanocomposites with tuned optical properties and hydrophobicity

AbstractThe fast advancements in technology have generated significant interest in optoelectronic materials. Nevertheless, the difficulty of creating affordable materials with exceptional optical characteristics is an ongoing challenge. Therefore, the objective of this work was to tune the optical properties of poly(methyl methacrylate) (PMMA) by embedding silver vanadate (SV) in the polymer matrix. Moreover, the wettability test of the fabricated composite membranes showed a hydrophobic behavior, with the PMMA film containing 0.6 wt.% SV showed a contact angle of 86.75 ± 0.7°. Furthermore, SV showed high thermal stability with a maximum weight loss of 0.74% at 830°C, which is very high thermal stability at high temperatures. In addition, the 0.6 wt.% SV@PMMA film exhibited a maximum weight loss of 96.7% at 785°C. Moreover, the 0.6 wt.% SV@PMMA film showed the lowest indirect band gap energy (2.02 eV) compared to the other films and pure SV NPs. The findings demonstrate the potential of the synthesized films for optoelectronic applications.

Optical, Structural, and Dielectric Characteristics of Flexible PVA/PEG/ZnMn2O4/CuCo2O4/x wt % Melanin Blended Polymer Composites

Our research described in the current paper was aimed to alter the optical and dielectric characteristics of polyvinyl alcohol/polyethylene glycol blended polymers by incorporating different quantities of melanin and ZnMn2O4/CuCo2O4 to create flexible blended polymer composites suitable for applications like photocatalysis, capacitors, and different optoelectronic applications. The PVA/PEG/ZnMn2O4/CuCo2O4-x wt % melanin blended polymer composites were created using a casting technique. The structural properties of the fillers and various blends were investigated using an X-ray diffraction technique. A transmittance electron microscope was used to investigate the features of the ZnMn2O4/CuCo2O4. The optical properties of the PVA/PEG/ZnMn2O4/CuCo2O4-x wt % melanin blend composites, which included their linear and nonlinear optical parameters, were analyzed using a diffused reflectance technique. The direct and indirect optical energy gaps attained their lowest values (5.47, 3.22, and 2.97) and (5, 1.18) eV in PVA/PEG/ZnMn2O4/CuCo2O4 blended polymer. The doped blends exhibited superior absorbance efficiency in the UV spectra in both the UVA and UVB regions. In the UV and visible ranges doped blends with 15 and 10 wt % of melanin had the highest refractive index values, respectively. The highest dielectric constant and electric ac conductivity were achieved as the blend was loaded with 5 wt % melanin. The energy density value of the doped blend containing 10% melanin was the highest when compared to other doped melanin polymers. The maximum height electrical potential barrier of each blend was also calculated. The electric modulus was also studied. The intensities of the emission peaks in terms of fluorescence characteristics were reduced as the PVA/PEG blend was loaded with ZnMn2O4/CuCo2O4-x wt % melanin. In conclusion, the PVA/PEG/ZnMn2O4/CuCo2O4-x wt % melanin blended polymer composites are promising hybrid materials for use in a variety of applications.

TiO2 doping promoted nucleation of CsPbX3 (X = Cl, Br, I) quantum dots in glass with improved luminescent performance and stability

Stability hinders further development of all-inorganic CsPbX3 (X = Cl, Br, I) quantum dots (QDs) although they exhibit promising prospects in optoelectronic applications. Coating perovskite quantum dots (PQDs) with a glass network to form QD glass can significantly improve their stability. However, the dense glass network degrades their luminescent performance. In this work, the crystallization behavior of PQDs in glass and better luminescence properties are prompted by introducing titanium dioxide into borosilicate glass. The luminescence intensity of TiO2-doped CsPbBr3 QD glass is increased by 1.6 times and the PLQY is increased from 49.8 % to 79 % compared to the undoped glass. Evidence proves that the improved properties are attributed to the enhanced nucleation effect of titanium dioxide during the annealing process. Benefiting from the densification of the glass network caused by titanium dioxide doping, the stability of the PQD glass is further improved. LED devices with an ultra-wide color gamut that fully covers the NTSC1953 standard and achieves 128.6 % of the NTSC1953 standard as well as 91.1 % of the Rec.2020 standard were fabricated by coupling PQD glass powder, demonstrating promising commercial applications of PQD glass in optoelectronic displays.

Development of a broadband photodetector utilizing ZnO nanorods with grating structure fabricated via nanoimprint lithography

Nanoimprint lithography (NIL) has emerged as a powerful technique for integrating nanostructures into semiconductor devices, particularly optoelectronic devices such as solar cells, light-emitting diodes (LEDs), lasers, and photodetectors (PDs). This study presents the successful fabrication of nano-patterned ZnO nanorods (ZnO NRs) using NIL, resulting in a grating structure with a linewidth of approximately 600 nm and a periodicity of around 1080 nm. Morphological characterizations, including scanning electron microscopy (SEM), atomic force microscopy (AFM), and laser confocal microscopy, reveal well-defined grating structures with ZnO NRs deposited on the substrate. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) further confirm the crystallinity of ZnO NRs, both with and without NIL treatment. X-ray photoemission spectroscopy (XPS) shows that the NIL-patterned samples with ZnO NRs exhibit fewer defects, attributed to the O2 plasma treatment during the NIL process. The NIL-defined grating structure of ZnO NRs is then employed in the fabrication of photodetectors, which demonstrate higher sensitivity than the pure ZnO-NRs-based PDs, presumably due to the reduce defects. Moreover, the NIL-defined PDs exhibit broadband photoresponses across the UV and visible light spectrum. This work introduces a novel device design for photodetectors and highlights the potential of NIL in creating broadband ZnO-based PDs, promising applications in future optoelectronics.

A comprehensive study of ferroelectric, dielectric and optical properties of europium-doped SBD metal- organic framework

The synthesis of Europium-doped Strontium based benzene dicarboxylate dimethylformamide metal–organic framework- Eu([Sr(μ-BDC)(DMF)])- with short form as Eu:SBD@MOF was carried out using the solvothermal method. The investigation involved characterization techniques such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), CHN analysis, and energy-dispersive X-ray (EDX) elemental analysis. The results confirmed the formation of metal–organic crystals in the framework. The XRD characterization shows good alignment with the simulated pattern of SBD. The experimental absorption spectrum displays distinct transitions of the Eu (III) ion alongside transitions of the ligands. Calculations of line strengths for all observed transitions have been conducted. The Judd-Ofelt theory has been employed to determine intensity parameters, transition probabilities, branching ratios, and radiative lifetimes for the Eu: SBD@MOF. These JO parameters further aid in calculating various excited state properties. When excited by ultraviolet and visible photons, the complex exhibits emission in the red region respectively. The crystal’s dielectric loss and dielectric constant were investigated for their frequency dependence. It was observed that by virtue of DMF, a molecule linked to the crystal, a synthesized MOF exhibits a good dielectric characteristic and when the temperature is raised to 558 K, the dielectric constant drops sharply as DMF molecule could not stand after this temperature. Further ferroelectric studies reveal that the Eu: SBD@MOF has maximum polarization of 0.27 C/cm2 which is greater than Rochelle salt and other MOF’s. Exploring the broadband dielectric response of metal–organic frameworks (MOFs) open up new avenues in research, potentially leading to innovative applications in smart optoelectronics, terahertz sensors, high-speed telecommunications, and microelectronics.

First principles investigations of optoelectronic and thermoelectric properties of novel BaMg2X2 (X = P, As, Sb) alloys for renewable energy applications

Zintl phase compounds are emerging candidates for solar cells due to their unique electronic structure and favorable optoelectronic characteristics. In the present communication, we have studied the structural, electronic, optical, and transport properties of BaMg2X2 (X = P, As, Sb) Zintl compounds. The computation of formation energy and analysis of phonon dispersion spectra confirm their favorable formation and dynamic stability. Employing modified Becke-Johnson (mBJ) potential, we elucidate the band structure for BaMg2P2, BaMg2As2, and BaMg2Sb2, revealing direct band gaps of 1.80, 1.65, and 1.35 eV, respectively. Examination of DOS spectra provides better insight regarding the contribution of 6 s-Ba, 3 s-Mg, and (3p-5p)-P/As/Sb states in forming valence and conduction bands. The scrutiny of the optical characteristics indicates compelling light absorption in the visible region, suggesting promising prospects for optoelectronic applications. Thermoelectric characteristics are evaluated using classical Boltzmann transport theory. Notably, large figure of merit values of 0.99, 0.97 and 0.95 for BaMg2P2, BaMg2As2, and BaMg2Sb2, respectively, have been observed at room temperature. These exceptional optoelectronic characteristics, coupled with outstanding ZT values, suggest the potential suitability of these compositions for solar cells and thermoelectric device applications.

Ab initio exploration of A2AlAgCl6 (A = Rb, Cs): unveiling potentials for UV optoelectronic applications.

In this study, we have explored the electronic and optical properties of A2AlAgCl6 (A = Rb, Cs), revealing their potential applications in UV devices. Our investigation demonstrates that Rb2AlAgCl6 and Cs2AlAgCl6 possess remarkable mechanical and thermodynamic stability, alongside direct band gaps of 4.25 eV and 4.20 eV, respectively. The optical properties, including the dielectric function, absorption coefficient, and reflectivity, underscore the suitability of these materials for UV device applications. This work serves as a foundational reference for future experimental endeavors aiming to leverage these characteristics for practical uses in scientific research. The study utilizes first-principles calculations based on the Wien2k code, employing GGA-PBE and mBJ exchange-correlation functional to analyze the cubic structure of the space group Fm-3m. Detailed computational analyses were conducted to investigate the band structure, density of states, and optical properties, particularly focusing on Cs2AlAgCl6. This methodological approach not only confirms the materials' impressive stability and optical characteristics but also provides a robust framework for assessing their potential in UV technology applications. Our computational strategy offers insights into the effectiveness of these methodologies for future experimental validation and practical deployment in the research domain.

Synergistic enhancement of optical properties in erbium-doped borate glasses through copper nanoparticle incorporation.

The present study investigated the impact of incorporating copper nanoparticles (CuNPs) on the optical properties of erbium-doped borate glasses. Through melt-quenching and heat treatment techniques, glasses with varying Cu2O concentrations (x=0-5 mol%) were synthesized. Physical and structural analyses revealed that Cu ions serve as effective network modifiers. They foster the formation of a greater proportion of BO4 tetrahedra and thus enhancing glass homogeneity. Optical absorption spectra demonstrate a distinct modulation of Er3+ absorption bands with Cu2O embedding, indicating the formation of CuNPs, as validated by the emergence of surface plasmon resonance bands. This structural evolution results in a noticeable reduction in the bandgap energy, signifying improved semiconducting behavior. Judd-Ofelt analysis highlighted the profound influence of CuNPs on hypersensitive transitions, thereby affecting oscillator strength. Photoluminescence measurements revealed amplified emission in the visible red and near infrared (NIR) region, attributed to the synergistic effects of CuNPs and Er3+ ions, with 5 mol % Cu2O exhibiting the highest emission intensity. Analysis of the radiative properties validates the enhancement of the emission cross-section, gain bandwidth, optical gain and radiative transitions. These enhancements contribute to a notable increase in the branching ratio from 0.91% to 5.41% accompanied by an increase in the quantum efficiency from ∼ 79% to ∼ 90%. Moreover, decay analysis revealed a notable enhancement in lifetime from 3.03 ms to 15.74 ms, which is indicative of enhanced radiative transitions. Overall, the incorporation of CuNPs into erbium-doped borate glasses facilitates significant enhancements in physical, structural, and optical properties. This positions them as promising materials for a wide array of optoelectronic applications. This comprehensive study sheds light on the complex interplay between CuNPs and erbium-barium borate glasses, offering valuable insights for the development of advanced optoelectronic materials with enhanced performance and functionality.

Realization of CO2 gas sensors and broadband photodetectors using metal/high-k CeO2/p-Si heterojunction

Realization of high-k dielectric oxide material-based devices such as photodetectors (PDs)/gas sensors fabricated on silicon substrate seems to be the utmost promising as a cost-effective approach to use in next generation optoelectronic field. We have explored metal/CeO2/p-Si heterojunction to construct as a broadband (BB) PD and CO2 gas sensor device. The effect of post-annealing procedure on photodetection and CO2 gas sensing characteristics were correlated using AFM, XRD, XPS, Raman and UV–Vis studies. At 0 V bias, the fabricated as-deposited Au/CeO2/p-Si PD device exhibits outstanding performance with enhanced responsivity of 85 AW−1 (at 910 nm), detectivity of 1.36×1015 Jones (at 850 nm), EQE of 1.3×104 % (at 850 nm), faster rise and fall times of 124 ms and 107 ms (at 900 nm). On the other hand, the photodetection characteristic parameters were slightly deteriorated as a function of annealing with respect to the as-deposited device. One of the causes for this fact was attributed to the increase in rms surface roughness (AFM) and decrease in absorbance of CeO2 thin film (UV–Vis). Additionally, Ag/CeO2/p-Si heterojunction was studied as a CO2 gas sensor and evaluated response/recovery times as a function of CO2 gas concentration. Sensing responses of CeO2 as-deposited, CeO2-400, CeO2-500, CeO2-600 and CeO2-700 °C were around 58, 60, 62, 81 and 90 %, respectively, when exposed to 200 ppm of CO2. Thus, we validate that the prospect of integrating enhanced performance in BB PDs and CO2 gas sensors using metal/CeO2/p-Si heterojunction could serve as a basic building block in near future optoelectronic applications. Furthermore, the effect of post-annealing temperature on the morphological, structural, BB photodetection and CO2 gas sensing properties were discussed in detail.

Electrical characterization of a single-crystalline Si quantum well formed by thermal oxidation of ultrathin silicon-on-insulator film (Al/SiO2:c-Si QW/n-Si) for optoelectronic applications

Electrical characterization of a single-crystalline Si quantum well formed by thermal oxidation of ultrathin silicon-on-insulator film (Al/SiO2:c-Si QW/n-Si) for optoelectronic applications

Investigation of Structural and Optoelectronic Integrity of Sm3+ Doped CaWO4 for LED Applications

Investigation of Structural and Optoelectronic Integrity of Sm3+ Doped CaWO4 for LED Applications

Electron beam irradiation-induced atomically thin domes of two-dimensional materials: Graphene and MoS[formula omitted]

The local strain-induced indirect-to-direct band gap transition in bulk transition metal dichalcogenides (TMDCs) holds great potential for optoelectronic applications. The formation of domes on the topmost layer of a multilayered flake through hydrogen ion H+ irradiation is an effective technique for tuning the band gap locally via molecular hydrogen (H2) confinement. In this work, we present an alternative robust, simpler, and faster technique for concurrently forming and visualizing dome-like structures of two-dimensional (2D) materials through low-energy electron beam irradiation. We investigated the growth mechanism and dynamics of the domes under exposure to electron beams at different energy levels. The simultaneous production and imaging of atomically thin domes of 2D materials has several practical and fundamental applications, such as mass storage and transport, single photon emission, nano/micro-electromechanical sensors, strain engineering, etc.

Manipulating 2D Materials through Strain Engineering.

This review explores the growing interest in 2D layered materials, such as graphene, h-BN, transition metal dichalcogenides (TMDs), and black phosphorus (BP), with a specific focus on recent advances in strain engineering. Both experimental and theoretical results are delved into, highlighting the potential of strain to modulate physical properties, thereby enhancing device performance. Various strain engineering methods are summarized, and the impact of strain on the electrical, optical, magnetic, thermal, and valleytronic properties of 2D materials is thoroughly examined. Finally, the review concludes by addressing potential applications and challenges in utilizing strain engineering for functional devices, offering valuable insights for further research and applications in optoelectronics, thermionics, and spintronics.

Tuning the band gap, optical, mechanical, and electrical features of a bio-blend by Cr2O3/V2O5 nanofillers for optoelectronics and energy applications

This work presents a facile approach for controlling the optical and electrical parameters of a biopolymeric matrix for optoelectronics. Vanadium oxide (V2O5) and chromium oxide (Cr2O3) nanoparticles (NPs) were prepared and incorporated into the carboxymethylcellulose/polyethylene glycol (CMC/PEG) blend by simple chemical techniques. Transmission electron microscopy (HR-TEM), and X-ray diffraction (XRD) data showed that V2O5 and Cr2O3 exhibited spherical shapes with sizes in the range of 40–50 nm and 10–20 nm, respectively. In addition, the blend's degree of crystallinity was sensitive to the V2O5 and Cr2O3 doping ratios. The scanning electron microscopy (FE-SEM) and the elemental chemical analysis (EDAX) used to study the filler distribution inside the blend, and confirmed the existence of both V and Cr in the matrix. Fourier transform infrared (FTIR) spectroscopy showed that the dopants significantly affected the blend reactive (C–O–C, OH, and C=O) groups. The stress–strain curves illustrated the reinforcing effect of the dopants up to 1.0 wt\\%\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ ext{wt\\%}$$\\end{document} Cr2O3/V. The transmittance and absorption index spectra in the visible-IR wavelengths decreased with increasing filler content. Utilizing Tauc's relation and (optical) dielectric loss, the direct (indirect) band gap narrowed from 5.6 (4.5) eV to 4.7 (3.05) eV at 1.0 wt\\%\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ ext{wt\\%}$$\\end{document} Cr2O3/V. All films have an index of refraction in the range of 1.93–2.17. AC conductivity was improved with increasing filler content and temperature. The energy density at 50 °C is in the range of 1–3 J/m3. The influence of V2O5 and Cr2O3 content on the optical conductivity, dielectric constant, loss, and dielectric modulus of CMC/PEG was reported. These enhancements in electrical and optical properties, along with the potential for band gap engineering, offer promising prospects for advanced applications in optoelectronics and energy-related fields.

Influence of pressure on structural, electronic, optical, and elastic properties of lead-free chalcogen perovskite LaLuS3 via first-principles calculations: implications for optoelectronic applications

Chalcogen perovskites have garnered increasing attention as promising materials for optoelectronic applications. In this study, we employed the first-principles method to investigate the structural, electronic, optical, and elastic properties of LaLuS3 under hydrostatic pressure at various levels. Through a thorough analysis of the calculated electronic structures, we observed that LaLuS3 exhibits direct band gaps, with the magnitudes of these gaps changing as the pressure varied. Specifically, the band gaps decrease by 2.19 eV, 2.025 eV, 1.365 eV, and 0.6043 eV at hydrostatic pressures of 0%, 10%, 20%, and 30% GPa, respectively. Furthermore, we observed shifts in the conduction band minimum and valence band maximum positions, indicating the potential of LaLuS3 for perovskite-based devices. This suggests that external pressure can serve as a powerful tool for designing new functional materials with intriguing properties. Our investigation also revealed promising optical properties of LaLuS3 under high pressures, further affirming its potential for optoelectronic and solar cell applications. The optical functions of the material are enhanced with increasing pressure, particularly in the ultraviolet range, highlighting its suitability for a wide range of optoelectronic devices. Moreover, while maintaining mechanical stability, hydrostatic pressure exerts a significant influence on the mechanical properties of LaLuS3. Lastly, our calculations on anisotropy demonstrate that applied pressure can enhance the anisotropic nature of LaLuS3. This comprehensive study underscores the efficacy of hydrostatic pressure as a systematic approach to modifying the photovoltaic performance of chalcogen perovskites.

Wavelength-tunable photoluminescence of CsPbBr3 microcrystal via in situ halogen doping

Lead halide perovskite semiconductors have received significant attention in recent years as promising candidates for optoelectronic applications. Their controllable bandgap in nanostructures (nanocrystals, nanowires) has been widely and successfully investigated. Intentionally manipulating the atomic behavior with dopants in their macroscopic structure with high quality and stability is still challenging. We studied the crystal structure and photoluminescence (PL) behavior of the anion (Cl) doped CsPbBr3 microcrystals. The doped microcrystal with a low doping concentration has shown a large wavelength-tunable PL emission from 535 nm to 457 nm. Two separate emission peaks (blue and green) are carefully studied in the excitation power dependent PL spectra. The doping and excitation endow the perovskite microcrystal adjustable PL emission band and peak intensities, which may serve as a new degree of manipulation freedom in the color-tunable display and functional optoelectronics.

Strain in Hybrid Organic-Inorganic Metal Halide Perovskites Microstructures by Numerical Simulations.

Hybrid organic-inorganic metal halide perovskites (HOIPs) are promising materials for optoelectronics applications. Their optical and electrical properties can be controlled by strain engineering, that results from application of local elastic deformation or deposition on pre-patterned substrates acquiring a conformal 3D shape. Most interesting, their mechanical properties depend on their crystal structure, composition and dimensionality. We explore by numerical simulations the deformation of a selection of HOIPs comprising a broad range of elastic properties. We consider an axial symmetry with the formation of microdomes on flakes. Radial and vertical forces are considered, finding that the radial force is more effective to obtain large deformation. Large vertical displacement and strain is obtained for HOIPs with low stiffness. The layered nature of HOIPs, that are formed by inorganic layers of different thickness and organic spacers, is also investigated, revealing a non-monotonous trend with the proportion of inorganic to organic part.

Novel vacancy-ordered RbKGeCl6 and RbKGeBr6 double perovskites for optoelectronic and thermoelectric applications: an ab-initio DFT study

The present study examines the key characteristics of new vacancy-ordered halide double perovskites, RbKGeCl6 and RbKGeBr6, encompassing the elastic, structural, mechanical, optoelectronic, and thermoelectric properties. The Density Functional Theory (DFT) was employed to perform the calculation of the properties, facilitating the evaluation of their potential applications in optoelectronic and thermoelectric devices. The DFT calculation was conducted using the Quantum Espresso package alongside the thermo_pw tool and the BoltzTraP codes. The results revealed that the two proposed compounds possess both chemical and mechanical stability with optimized lattice constants recorded at 10.14 Å and 10.72 Å for RbKGeCl6 and RbKGeBr6, respectively. The evaluation of the elastic properties of the materials suggested reasonably high mechanical moduli of the materials. Based on the calculated electronic properties, the materials are classified as direct gap semiconductors, with energy gap values of 2.11 eV for RbKGeCl6 and 0.80 eV for RbKGeBr6 using the GGA-PBE functional. Furthermore, the use of the SCAN approximation yields more reliable energy gap of 2.51 eV and 1.08 eV for the respective compounds. The materials exhibited a high absorption coefficient and a significantly low reflectivity within the visible-ultraviolet energy spectrum. These findings strongly suggest the promising properties of the materials under study for optoelectronic applications. Furthermore, the calculated thermoelectric properties of the materials, particularly the figure of merit, revealed the materials’ potential use as thermoelectric materials. The calculated figure of merit values of RbKGeCl6 and RbKGeBr6 were found to range from 0.73 to 0.75, respectively, between 300 K and 800 K. Despite being lower, these values are comparable to those of some well-established materials including SiGe alloys (0.95), Bi2Te3 (≈0.90), and PbTe (≈0.80).