Structural, Electronic, Stability, and Optical Properties of CsPb_1–xSn_xIBr₂ Perovskites: A First-Principles Investigation

Abstract

Recently, exploration of stabler and lead-free perovskite absorbers with better cost-effective processability and prominent lightharvesting capacity has attracted extensive attentions. Inorganic Cs-based halide perovskites are outstanding in enormous functional materials for their improved long-term stability. In this study, we performed a first-principles investigation based on density functional theory to explore the structural, electronic, stability, and optical properties of both cubic (α) and orthorhombic (γ) phases CsPb 1−x Sn x IBr 2 (x = 0, 0. 25, 0.5, and 0.75). According to our calculations, the energy conversion properties tend to be controlled by the new hybrid states of Sn 2+ and Pb 2+ with doping of Sn atoms. The calculated formation energies, phase stability diagram analysis, electron localization function, and charge density distribution of these mixed pervoskites demonstrate that they are the most stable among all of the doped CsPb 1−x Sn x IBr 2 perovskite series. Notablely, α-CsPb 0.25 Sn 0.75 IBr 2 and γ-CsPb 0.75 Sn 0.25 IBr 2 show the strongest absorption within the visible light range, maximum amount of photons absorbent, remarkably stability, and suitable band gaps. Our study provides theoretical insight into the rationale design of highly efficient and stable inorganic halide perovskite photovoltaic devices and sheds a new light on designing and synthesizing the next generation of photovoltaic materials.

Kinetically Controlled, Scalable Synthesis of γ‐FeOOH Nanosheet Arrays on Nickel Foam toward Efficient Oxygen Evolution: The Key Role of In‐Situ‐Generated γ‐NiOOH

“…[ 31 ] The electron localization function (ELF) of Fe and Ni in the heterostructure is 0.63 and 0.45, respectively, higher than the values in γ‐FeOOH (0.51) and γ‐NiOOH (0.38), indicative of electron localization of the metal sites (Figure 5c). [ 31,32 ] The relatively higher ELF of Fe compared with Ni further confirms the charge accumulation at the Fe sites and is coincident with the XPS analysis (Figures S20 and S22, Supporting Information). Subsequently, a typical four‐step mechanism is adopted to analyze the OER reaction kinetics of γ‐FeOOH@γ‐NiOOH.…”

New p-type Al-substituted SrSnO3 perovskites for TCO applications?

“…The impact of the Sn(IV)/Al(III) substitution ratio on the macroscopic properties of SrSn 1-x Al x O 3 was investigated through complementary XRD and SEM-EDX. The structural and morphological analyses of the synthesized samples are presented in Fig.1 31,32 which confirms the phase stability. Note that a small amount of SrCO 3 impurity was detected and attributed to the potential reaction of Sr defects with atmospheric oxygen and carbon dioxyde.…”

Anion Substitution Effects on the Structural, Electronic, and Optical Properties of Inorganic CsPb(I1–xBrx)3 and CsPb(Br1–xClx)3 Perovskites: Theoretical and Experimental Approaches

“…Table S1 shows a comparison of the equilibrium lattice constants ( a , b , and c ) of CsPbI 3 , CsPbBr 3 , CsPbCl 3 , and their mixed structures with those reported elsewhere. ,,− Figure S3a,b shows the theoretical and experimental XRD patterns in the range 28.5° ≤ 2θ ≤ 33°. As noted in Table S1 and Figure S3a–d, the lattice parameters and unit-cell volume decrease in proportion to x , where the volume decreases according to the functions V ( x ) = 2013.06474–432.10545 x (Å) 3 and V ( x ) = 1585.66658–152.98318 x (Å) 3 for CsPb­(I 1– x Br x ) 3 and CsPb­(Br 1– x Cl x ) 3 , respectively.…”