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In recent times, there has been a pressing need to discover or manufacture a unique material that can serve as a photocatalyst for organic pollutants that are incapable of degradation. Pure Bi 2 O 3 and Co, Cd co-doped Bi 2 - 2x Co x Cd x O 3 (x = 0.8) nanoparticles were synthesized using the chemical co-precipitation method, but the new approach involves fabricating 10 % reduced graphene oxide Bi 2 - 2x Co x Cd x O 3 /rGO nanocomposites via the ultra-sonication route. This study investigated the effects of Co, Cd, and r-GO doping on the optical, electrochemical, structural, and photocatalytic properties of bismuth oxide. The synthesized nanomaterials were analyzed using X-ray diffraction (XRD), cyclic voltammetry, ultraviolet–visible (UV–Vis), Fourier transform infrared (FTIR), photoluminescence (PL), and Raman spectroscopy. The XRD patterns showed the formation of a monophasic monoclinic structure belonging to space group P21/c, with an average crystallite size estimated around 22–41 nm. According to the UV–visible study, the bandgap energy of Bi 2 O 3 NPs, Bi 2 - 2x Co x Cd x O 3 NPs, and Bi 2 - 2x Co x Cd x O 3 /rGO nanocomposites were 2.64 eV, 2.37 eV and 2.06eV respectively. The cyclic voltammetry technique was used to evaluate the functioning electrodes. In contrast to un-doped Bi 2 O 3 , the synergistic effects of Co, Cd, and r-GO on the substituted material increased the specific capacitance. The pure Bi 2 O 3 , doped Bi 2 - 2x Co x Cd x O 3, and Bi 2 - 2x Co x Cd x O 3 /rGO photocatalyst degraded 62 %, 85 %, and 95.4 % respectively of RB-5 dye after 105 min of sunlight. The phytotoxicity analysis examined the germination of Hordeum vulgare seeds in treated and untreated RB-5 dyes. Additionally, scavenging investigations using reactive species trapping to confirm the dominant reactive species were evaluated. Bi 2 - 2x Co x Cd x O 3 /rGO nanocomposites are better at photocatalysis and have a narrow bandgap, which makes them useful as solar-active photocatalysts for getting rid of dyes in wastewater. In future, their composites with conducting polymers may improve their electrochemical and photocatalytic behaviour as well. [ABSTRACT FROM AUTHOR]

Microwave absorption materials have attracted attention due to their extensive applications in different fields. Herein, ytterbium-doped BaCo 2 W-type hexaferrite nanocrystallites with a nominal composition of BaCo 2 Yb x Fe 16−x O 27 (x = 0.00, 0.03, 0.06, 0.09, and 0.12) were synthesized via the sol–gel method, and their physicochemical and dielectric characteristics were estimated. XRD plots revealed the pure phase structure of each prepared hexaferrite sample. The lattice constant and unit cell volume were affected by changes in the Yb concentration. The crystallite size was measured by the Debye–Scherrer formula, revealing intense crystals typically in the 18–33 nm range. FTIR spectroscopy showed multiple absorption bands from 430 to 3000 cm−1, and Raman spectroscopy revealed multiple peaks between 200 and 1000 cm−1, displaying the allocated polyhedra and symmetry. XPS spectroscopy confirmed the existence of all metal ions in the required valence state. The dielectric measurements were evaluated at frequencies from 1 to 6 GHz for all the synthesized compositions, and the material behavior was explained using the Maxwell–Wagner and Koop theories. The conduction mechanism in the hexagonal ferrites was assessed using Cole–Cole analysis. Reflection loss measurements were also conducted: the samples at x = 0.03 and x = 0.12 yielded minimal reflection losses of −60.06 and −51.69 dB at 5.5 GHz, respectively. The results demonstrate the suitability of the samples for use in microwave and high-frequency absorption applications. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) substituted for CrCd x Fe 1-x O 3 (x = 0.0, 0.025, 0.050, 0.075) nanocrystallites were prepared using the sol-gel technique. The synthesized materials were sintered at 700 °C for 4 h to obtain the CrCd x Fe 1-x O 3 phase. The XRD analysis evidenced the formation of a single-phase rhombohedral structure of all the synthesized materials. The crystallite size values of prepared samples lie in the nanoscale range (37–42 nm). Rietveld refinement endorsed materials' pure-phase rhombohedral structure. Cationic distribution and the Wykoff position are also derived from Rietveld refinement results. A 3D crystal structure was drawn using a CIF file from refinement results. The vibrational band ν 1 oscillates from 492 to 502 cm−1 due to substituting Cd2+ at the tetrahedral site, while ν 2 remains unaltered. XPS results verified the existence of all metal ions and their related electronic state. The electrical transport features were evaluated at microwave frequency. The values of dielectric parameters were optimized with frequency and Cd2+ substitution. Grain boundary contribution was elucidated by impedance Cole-Cole plots. The minimum reflection loss of −57 dB suggested the potential use of these materials in microwave absorption applications. [ABSTRACT FROM AUTHOR]

• Anti perovskites are emerging Aspirant for solar cells. • The large value of thermoelectric and optical efficiencies. • The absorption bands exist visible to infrared region. • The large figure of merit at room temperature. • Structral and dynamical stable structures. Perovskites and their inverse derivatives are emerging aspirants for solar cells and energy harvesting applications. Herein, we have comprehensively addressed the phase stability, optical, and transport characteristics of X 3 GeO (X=Ca, Sr, Ba) antiperovskites by first-principles analysis. The studied compounds have an orthorhombic crystal structure with a space group (1-P1). The phonon spectra have been computed to assess the dynamic stability. The electronic band structures demonstrate that perovskites have narrow band gaps, while the antiperovskites are narrow band gap semiconductors. The calculated values of band gaps for antiperovskites are 0.38, 0.63, and 0.70 eV, respectively, suggesting optimal absorption in infrared to visible regions. Light energy's dispersion and absorption are calculated by a complex dielectric function, refractive index, and absorption coefficient in the energy range 0 to 5 eV. The Seebeck coefficient, electrical & thermal conductivities, and power factor assess thermoelectric performance at increasing temperatures and carrier concentration. The findings convey a theoretical foundation for future experimental investigations of these antiperovskites and suggest their effectiveness for optoelectronic, and thermoelectric applications to harvest green energy. [ABSTRACT FROM AUTHOR]

Photocatalysis is commonly regarded as a perfect solution to the anticipated fuel crisis and ecological issues. ZnO is considered an efficient photocatalyst because of its low cost, abundance, effective stability, and suitable redox potentials. However, the limited visible light response, low surface area, small quantum yield, and swift recombination loss of photoinduced electron-hole pairs are the drawbacks of ZnO. Nonetheless, the construction of a heterostructure system by integrating ZnO with suitable semiconductors has been found to overcome the inherent limitations of ZnO. Nevertheless, the design of ZnO-based heterostructure photocatalysts has also encountered some barriers. Herein, we overview the design strategies and corresponding challenges to obtain efficient ZnO-based heterostructured photocatalysts. Finally, the recent barriers and perspectives of ZnO-based heterostructured photocatalysts have been also added to highlight the excellent future and important status of ZnO materials for photocatalytic applications. [ABSTRACT FROM AUTHOR]

Structural geometry, Electronic, optical, and thermoelectric attributes of XAcTe 2 (X = K , Rb) full Heuser alloys were investigated theoretically via density functional theory (DFT). Structural optimization yielded optimized lattice parameters along with obtained negative formation energies (E f) revealed the thermodynamically stable cubic geometries of alloys under investigation. For both alloys, the computed electronic band dispersions exhibit semiconductor behavior with a direct band gap. The band gap value of KAcTe 2 is 1.59 eV, and 1.66 eV for RbAcTe 2. The analysis of optical response shows maximum absorption α (ω) in the ultraviolet (UV) region, validating their quality for photovoltaic devices. The investigation of thermoelectric characteristics showed that both alloys display higher electrical conductivities and lower thermal conductivities. • Physical properties of Two novel Heusler alloys KAcTe 2 and RbAcTe 2 have been explored. • Electronic bandgap of KAcTe 2 is 1.59 eV, while RbAcTe 2 exhibit bandgap of 1.66 eV. • Both alloys are optically active in visible region of light. • Both alloys possess thermoelectric ZT values close to unity. [ABSTRACT FROM AUTHOR]

The search of stable, lead-free absorber material for perovskite solar cells (PSC) resulted in many alternatives, particularly, zinc (Zn) doped formamidinium tin iodide (FASnI 3). This work facilitates in investigating the behavior of four different Zn doping ratios 0 %, 2 %, 5 %, and 10 % (say Zn-0, Zn-2, Zn-5, and Zn-10) on the performance of FTO/PCBM/FASnI 3 :Zn2+/MoO x /Au solar cell structure. A precise evaluation on the impact of the four various Zn doping ratios in the mentioned solar structure in terms of thickness of perovskite absorber layer, hole transport layer, and electron transport layer were executed. The investigation through numerical study further deals with the role of interfacial defect density and capture cross-section of charge carriers on the performance of suggested PSCs with varying Zn doping ratios. It is evident from the optimization results that PSC having absorber layer thickness of 400 nm yields better power conversion efficiency (PCE) of 11.49 % for Zn-5. The PCE is further improved to 13.98 % for capture cross section of 2 ×10−15 cm2. The entire work witnessed distinguishable superior behavior from FASnI 3 -based PSC doped with Zn ratio: Zn-5 in comparison to the PSCs doped with other Zn ratios. Furthermore, impact of the series and shunt resistances on performance parameters are also examined. [ABSTRACT FROM AUTHOR]

Modification of terminal acceptors of non-fullerene organic solar cell molecule with different terminal acceptors can help in screening of molecules to develop organic photovoltaic cells with improved performance. Thus, in this work, seven new molecules with an unfused core have been designed and thoroughly investigated. DFT/TD-DFT simulations were performed on studied molecules to explore the ground and excited state characteristics. UV–Visible analysis revealed the red shift in the absorption spectrum (reaching 781 nm) owing to their smaller energy gap up to 1.94 eV. Furthermore, transition density matrix analysis demonstrated that peripheral acceptors extract the electron density from the core effectively. The effectiveness of our investigated molecules as materials for high-performing organic photovoltaic cells has been shown by an examination of their electron and hole mobilities for fast charge transfer. When combined with PTB7-Th, all molecules displayed high open circuit voltage. XP5 molecule exhibited highest open circuit voltage (1.70 eV) and lowest energy loss of 0.30 eV. All designed molecules exhibit the improved aforementioned parameters, which shows that these molecules can be used to develop competent solar devices in future. [Display omitted] • Seven molecules are designed by modifying the terminal electron-rich moiety of A-C-A configured X–PCIC with highly efficient electron withdrawing electron acceptors. • All molecules were processed computationally by Gaussview 6.0 and Gaussian 9.0 software. • Designed molecules outperform the reference molecule in terms of light harvesting efficiencies, electron and hole mobilities, and electronic cloud dispersion. • Proposed molecules show improved open circuit voltage and FF, making them a superior choice compared to the reference molecule. • All studied molecules displayed a more favorable optoelectronic response, and thus preferred to be utilized in the construction of high-performance OSCs. [ABSTRACT FROM AUTHOR]

With the goal of developing a high-performance organic solar cell, nine molecules of A 2 -D-A 1 -D-A 2 type are originated in the current investigation. The optoelectronic properties of all the proposed compounds are examined by employing the DFT approach and the B3LYP functional with a 6-31G (d, p) basis set. By substituting the terminal moieties of reference molecule with newly proposed acceptor groups, several optoelectronic and photovoltaic characteristics of OSCs have been studied, which are improved to a significant level when compared with reference molecule, i.e., absorption properties, excitation energy, exciton binding energy, band gap, oscillator strength, electrostatic potential, light-harvesting efficiency, transition density matrix, open-circuit voltage, fill factor, density of states and interaction coefficient. All the newly developed molecules (P1–P9) have improved λ max , small band gap, high oscillator strengths, and low excitation energies compared to the reference molecule. Among all the studied compounds, P9 possesses the least binding energy (0.24 eV), P8 has high interaction coefficient (0.70842), P3 has improved electron mobility due to the least electron reorganization energy (λ e = 0.009182 eV), and P5 illustrates high light-harvesting efficiency (0.7180). P8 and P9 displayed better V oc results (1.32 eV and 1.33 eV, respectively) and FF (0.9049 and 0.9055, respectively). Likewise, the phenomenon of charge transfer in the PTB7-Th/P1 blend seems to be a marvelous attempt to introduce them in organic photovoltaics. Consequently, the outcomes of these parameters demonstrate that adding new acceptors to reference molecule is substantial for the breakthrough development of organic solar cells (OSCs). [Display omitted] • A series of seven molecules (P1–P9) were designed. • Various optoelectronic and photovoltaic properties of molecules were studied using DFT. • A narrow bandgap, low excitation energy and improved light absorption was observed in newly presented molecules. • P9 showed significantly improved open circuit voltage and fill factor. • Results demonstrate that new molecules have potential to be used as advanced organic solar cells. [ABSTRACT FROM AUTHOR]

The quest for new Zintl phases with promising thermoelectric properties has gained significant momentum recognitions to the precision of computational predictions. Our study presents an in-depth investigation of fundamental characteristics like structural, optoelectronic, optical, and transport aspects of BaCd 2 X 2 (X = P, As, Sb) Zintl compounds. The stability of all compounds is firmly established through their optimized negative (-ve) formation energies and phonon dispersion spectra. Our findings affirm their robust structural integrity. Notably, we observe a semiconductor nature in these compounds, with calculated bandgap values of 1.35 eV for BaCd 2 P 2 , 0.85 eV for BaCd 2 As 2 , and 0.23 eV for BaCd 2 Sb 2. Probing into optical properties, we uncover their potential utility in optoelectronic devices, as indicated by the optical response of these phases. We employ semi-classical Boltzmann theory, executed via BoltzTraP code, to explore their thermal behavior. Impressively higher values of Seebeck are attained, both at RT and elevated temperatures. Furthermore, the power factor exhibits an increasing trend with increasing temperature. Crucially, the analysis of the figure of merit (ZT) reveals promising values, 0.90, 0.81, and 0.72 for BaCd 2 X 2 (X = P, As, Sb) at 300 K, respectively. These favorable optical and thermoelectric characteristics position these phases as attractive candidates for applications in optoelectronics and thermoelectric systems. • Novel Zintl-Phase materials are more stable, cheap, and suitable for solar cells. • The maximum conversion efficiency of light energy into electrical energy. • The absorption of light falls in the visible to infrared region. • Ultralow thermal conductivity, and significant values of figure of merit. [ABSTRACT FROM AUTHOR]

• A triple-cation coupled with multi-halide perovskite-based solar cells (PSCs) were studied. • Post-growth passivation using formamidinium bromide (FABr) corrects phase problems and improves performance. • A numerical analysis compares FABr-passivated and unpassivated PSCs, assessing several parameters. • FABr passivation reduces the recombination rate by approximately 32%. • FABr treatment boosts power conversion efficiency (PCE) to 24.62% from 22.25%. In order to preserve the effectual potential of triple-cation coupled with multi-halide perovskites (PVTs), the phase-related conflict amongst different precursors has to be resolved. There arises the necessity of post-growth passivation treatments, especially using formamidinium bromide (FABr) upon such PVT films. In this research, a methodical comparison assessment is performed on triple-cation, multi-halide (CsFAMAPbIBr)-based PVT solar cells (PSCs) with and without FABr passivation using numerical study. A meticulous estimation of all the performance parameters of both PSCs was implemented in accordance with transformations in thickness, effective density, and acceptor density of the PVT absorber layer together with the charge transport layer thickness variations. The investigation revealed that the charge carrier generation rate remained the same after FABr passivation, however, the recombination rate was lowered by ∼ 32 % (from 7.27 × 1021 to 4.92 × 1021 cm-3s−1). The analysis discerned that at minimum valence band effective density of PVT absorber: 1 × 1017 cm−3, FABr-treated CsFAMAPbIBr-based PSC ensures the highest power conversion efficiency of 24.62 % against its un-passivated correspondent of 22.25 %. Further, this investigation imparts the remarkableness of FABr passivation treatment in regulating the overall performance of triple-cation and multi-halide-based PSCs. [ABSTRACT FROM AUTHOR]