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Lead‐free tin halide perovskites, particularly Cs2SnBr6, are gaining significant attention for their potential in optoelectronic applications. In this study, we investigate the material's electrical and vibrational properties under varying illumination conditions, providing novel insights into the impact of light on its conduction mechanisms. Cs2SnBr6 was synthesized via liquid‐phase and solid‐state reactions, and we report comprehensive analyses of its impedance, AC conductivity, and dielectric properties over a wide frequency range. Notably, our results reveal that light‐induced photogenerated charge carriers enhance conductivity, which is well explained by the overlapping large‐polaron tunneling (OLPT) model, while in darkness, the material follows the correlated barrier hopping (CBH) model. Moreover, Raman spectroscopy highlights structural changes, including a slight shortening of Sn–Br bond distances under illumination, which influences the vibrational frequencies and intensities. These findings emphasize the crucial role of illumination in tuning the electrical and dielectric responses of Cs2SnBr6, thus demonstrating its considerable promise for future optoelectronic applications, such as solar cells and photodetectors. [ABSTRACT FROM AUTHOR]

In recent times, double perovskites have demonstrated promising potential as an alternative to address the instability and toxicity challenges associated with lead halide perovskites in optoelectronic applications. In this study, we successfully prepared Cs2MSbBr6 (M = Cu, Ag) double perovskite materials using the slow evaporation solution growth technique. The X-ray diffraction pattern confirmed the presence of the cubic phase in these synthesized materials. Furthermore, the optical analysis of Cs2CuSbBr6 and Cs2AgSbBr6 revealed their respective indirect bandgap energies to be 1.72 and 2.0 eV. The impedance spectroscopy technique was employed to investigate the properties of these materials, specifically double perovskites, across a frequency range of 10−1 to 106 Hz and at temperatures ranging from 303 to 403 K. To describe the AC conductivity, Jonscher's power law was utilized. The findings of the charge transportation study on Cs2MSbBr6 (M = Cu, Ag) indicate the existence of the non-overlapping small polaron tunneling mechanism in Cs2CuSbBr6, while the overlapping large polaron tunneling mechanism is observed in Cs2AgSbBr6. [ABSTRACT FROM AUTHOR]

This study offers an extensive exploration into approaches for cultivating CsPbBr3 SCs using inverse temperature crystallization (ITC), with a specific focus on seed-induced (method (1)) and nucleation-mediated (method (2)) growth techniques. Our findings reveal that leveraging seed-assisted growth at lower temperatures yields noteworthy enhancements in the material's optical and electrical behaviors, outperforming the outcomes achieved through nucleation-driven growth. Concretely, through the employment of the space charge limited current (SCLC) technique, an evident contrast emerges in the trap-populated threshold voltage between the seed-facilitated crystal (SC1) (measuring 0.309 V) and its nucleation-facilitated counterpart (SC2) (measuring 1.513 V), consequently giving rise to discernable dissimilarities in trap density assessments. Evidence from temperature-dependent analysis of space charge limited currents substantiates these findings, revealing trap density values of 8.81 × 109 cm−3 for SC1, juxtaposed with 2.08 × 1010 cm−3 for SC2. Additionally, the SC1 displays a notably diminished trap energy level. Furthermore, the investigation underscores the affirmative influence of method (1) at lower temperatures on the optical and crystalline characteristics of the substance. This effect is evidenced by enhanced photoluminescence (PL) reactions and reduced lattice strain (Ls), as determined through X-ray diffraction (XRD) techniques. Moreover, the research establishes the substantial impact of this enhanced crystallization technique on the photodetector (PD) attributes of the crystal. This effect induces elevated levels of detectivity and responsivity for method (1). [ABSTRACT FROM AUTHOR]

Lead-free halide double perovskites A2MM′X6 (A = Rb+, Cs+, etc.; M = Ag+, K+, Li+; M′ = Sb3+, In3+ or Bi3+ and X = I−, Br− or Cl−) have recently been suggested as an alternative to lead-based halide perovskites for optoelectronic and photovoltaic applications. While a great deal of effort has been put into device engineering to improve the performance of photovoltaic and optoelectronic devices that are based on A2MM′X6 double perovskites, there has been relatively little attention given to their inherent photophysical properties. The current research demonstrates that small polaron formation under photoexcitation and polaron localization limit the carrier dynamics in the Cs2CuSbCl6 double halide perovskite. In addition, temperature-dependent AC conductivity measurements indicate that single polaron hopping is the primary conduction mechanism. The ultrafast transient absorption spectroscopy results revealed that the formation of small polarons, which function as self-trapped states (STSs) and result in the ultrafast trapping of charge carriers, are caused by a distorted lattice under photoexcitation. These findings provide a thorough understanding of the intrinsic restrictions of Cs2CuSbCl6 perovskite and could have relevance for other antimony-based semiconductors. [ABSTRACT FROM AUTHOR]

The use of solid-state electrolytes (SSEs) instead of liquid organic electrolytes presents one of the important means to increase the energy density and resolve the protection issues of lithium batteries. The development of SSEs compounds, which can suit high-voltage cathodes and lithium metal anode (LMA) is rather important to progress high-energy–density lithium batteries. Among the different compounds, lithium aluminum titanium phosphates (LATP) are especially potential candidates for all-solid-state batteries (ASSBs) since their present high ionic conductivity, superior air stability, and low cost. In this paper, the Li1+xAlxTi2−x(PO4)3 (LATP) compounds with different mixtures have been synthesized via solid-state technique. The rhombohedral phase (space group R 3 ¯ c ) of these samples is confirmed through the powder X-ray diffraction measurements. The thermogravimetric (TG) measurements show that when x-content increments in LATP, the integral temperature of decomposition reduces. Likewise, the temperature whereupon the samples turn stable decreases, which suggested that phase stability is related by the rise of the x-content in the basic sample. Through the 101–106 Hz frequency area, the real and imaginary parts of the dielectric permittivity, the electric modulus, and alternating current (AC) conductivity of LATP samples display temperature reliance. The different contributions of grains and grain boundaries to the total impedance are confirmed by the Nyquist curves. The alternating current (AC) conductivity is illustrated in terms of Jonncher's power law. The studies on charge transportation suggest the presence of the overlapping large polaron tunneling mechanism (LATP − x = 0.0) and the non-overlapping small polaron tunneling mechanism (LATP − x = 0.3 and LATP − x = 0.5). [ABSTRACT FROM AUTHOR]

This study offers an extensive exploration into approaches for cultivating CsPbBr 3 SCs using inverse temperature crystallization (ITC), with a specific focus on seed-induced (method (1)) and nucleation-mediated (method (2)) growth techniques. Our findings reveal that leveraging seed-assisted growth at lower temperatures yields noteworthy enhancements in the material's optical and electrical behaviors, outperforming the outcomes achieved through nucleation-driven growth. Concretely, through the employment of the space charge limited current (SCLC) technique, an evident contrast emerges in the trap-populated threshold voltage between the seed-facilitated crystal (SC 1 ) (measuring 0.309 V) and its nucleation-facilitated counterpart (SC 2 ) (measuring 1.513 V), consequently giving rise to discernable dissimilarities in trap density assessments. Evidence from temperature-dependent analysis of space charge limited currents substantiates these findings, revealing trap density values of 8.81 × 10 9 cm -3 for SC 1 , juxtaposed with 2.08 × 10 10 cm -3 for SC 2 . Additionally, the SC 1 displays a notably diminished trap energy level. Furthermore, the investigation underscores the affirmative influence of method (1) at lower temperatures on the optical and crystalline characteristics of the substance. This effect is evidenced by enhanced photoluminescence (PL) reactions and reduced lattice strain ( L s ), as determined through X-ray diffraction (XRD) techniques. Moreover, the research establishes the substantial impact of this enhanced crystallization technique on the photodetector (PD) attributes of the crystal. This effect induces elevated levels of detectivity and responsivity for method (1).

Lead-free halide double perovskites A 2 MM'X 6 (A = Rb + , Cs + , etc. ; M = Ag + , K + , Li + ; M' = Sb 3+ , In 3+ or Bi 3+ and X = I - , Br - or Cl - ) have recently been suggested as an alternative to lead-based halide perovskites for optoelectronic and photovoltaic applications. While a great deal of effort has been put into device engineering to improve the performance of photovoltaic and optoelectronic devices that are based on A 2 MM'X 6 double perovskites, there has been relatively little attention given to their inherent photophysical properties. The current research demonstrates that small polaron formation under photoexcitation and polaron localization limit the carrier dynamics in the Cs 2 CuSbCl 6 double halide perovskite. In addition, temperature-dependent AC conductivity measurements indicate that single polaron hopping is the primary conduction mechanism. The ultrafast transient absorption spectroscopy results revealed that the formation of small polarons, which function as self-trapped states (STSs) and result in the ultrafast trapping of charge carriers, are caused by a distorted lattice under photoexcitation. These findings provide a thorough understanding of the intrinsic restrictions of Cs 2 CuSbCl 6 perovskite and could have relevance for other antimony-based semiconductors.