UMYU Scientifica

A periodical of the Faculty of Natural and Applied Sciences, UMYU, Katsina

ISSN: 2955 – 1145 (print); 2955 – 1153 (online)

ORIGINAL RESEARCH ARTICLE

First-Principles Study of the Structural, Mechanical, and Electronic Properties of Ba₃AsCl₃ Perovskite for Optoelectronics and Solar Cell Applications

Yusra Sade Abdullahi^1,2, Garba Babaji², Abdullahi Lawal³, Abdulkadir S. Gidado²

¹ Department of Physics, Umaru Musa Yar’adua University, Katsina, Katsina State, Nigeria

² Department of Physics, Bayero University Kano, Kano State, Nigeria

³ Department of Physics, Ahmadu Bello University, Zaria, Kaduna State, Nigeria

Corresponding Author: Yusra Sade Abdullahi yusra.sade@umyu.edu.ng

Abstract

Inorganic lead-free halide perovskites with the A₃BX₃ structure have recently attracted considerable attention in recent years due to their excellent optoelectronic properties. Ba₃AsCl₃, a pnictogen-based inorganic halide perovskite, emerges as a promising candidate owing to the chemical stability of barium-based crystal structures and the potential of arsenic-derived compounds to exhibit favourable electronic structures. This study presents a detailed first-principles calculation of the structural, elastic, mechanical, and electronic properties of Ba₃AsCl₃ inorganic lead-free perovskite using the Quantum Espresso code. The generalized gradient approximation (GGA) with Perdew–Burke–Ernzerhof (PBE) functional was used to determine the electron exchange and correlation energy. Geometry optimization and variable-cell relaxation verify the stability of the compound in its cubic phase with an optimized lattice parameter of 6.49 \(\mathring{\mathrm{A}}\). This is in good agreement with available theoretical data. The calculated elastic constants indicate that Ba₃AsCl₃ is mechanically stable with a shear modulus of 16.03 GPa, a Young modulus of 40.01 GPa, and a bulk modulus of 27.01GPa. The calculated machinability index, Hardness, and anisotropy index indicate that Ba₃AsCl₃ has a high machinability index, moderately hard and anisotropic in nature, while Poisson's ratio of 0.251 and the negative value of the Cauchy pressure indicate that it is slightly brittle in nature. Electronic properties investigation reveals that Ba₃AsCl₃ is a direct band gap semiconductor with a band gap value of 0.934eV (with SOC) and 0.976 eV (without SOC). The density of states (DOS) and PDOS show the conduction band minimum, and the valence band maximum located along the high symmetry point Γ, and the contributions of the orbitals in the electronic state. Ba₃AsCl₃’s bandgap enables near-infrared absorption and efficient charge generation. Overall, this study offers valuable insights into the properties of Ba₃AsCl₃, suggesting potential for optoelectronics and solar cell applications.

Keywords: Perovskites, Ba₃AsCl₃, DFT, Optoelectronics, Solar Cell.

STUDY’S EXCERPT

This study presents a theoretical investigation of Ba₃AsCl₃, expanding the existing library of perovskite materials considered for optoelectronics and solar cell applications, thus filling a knowledge gap in inorganic halide perovskites.

This research presents detailed insights into the structural, elastic, mechanical, and electronic properties (with and without SOC) of Ba₃AsCl₃, offering a foundational reference for experimentalists and future computational studies.

The elastic constants and mechanical moduli calculated confirm the mechanical stability and slightly brittle nature of Ba₃AsCl₃, an important criterion for the practical fabrication of thin films and device architectures in solar cells.

The study confirmed that Ba₃AsCl₃ has a direct band gap, suggesting that It could serve as an efficient light-absorber material in optoelectronic or photovoltaic devices such as solar cells.

This study can guide experimental research on Ba₃AsCl₃ perovskite, including synthesis, characterization, and device fabrication, thereby accelerating the development of new optoelectronic and solar cell technologies.

1.0 INTRODUCTION

With the increasing global energy demand and growing concerns over environmental degradation, the shift toward renewable energy has become necessary. Among the various alternatives, solar energy is notable for its wide availability and sustainability (Gayen et al., 2024; Shahzad, 2012; Ukoba et al., 2024). Consequently, significant research efforts have focused on improving solar energy conversion technologies. Although many materials have been developed for solar cell technology, achieving low-cost, non-toxic, abundant, and efficient solar cell materials remain challenging for researchers (Lawal et al., 2021).

Perovskite solar cells have attracted significant attention due to their exceptional light-absorption properties and ease of fabrication. The rapid advancement in optoelectronics, particularly in the development of high-performance solar cells and photodetectors, has been fuelled by the outstanding properties of perovskite materials (Zhang et al., 2023). These materials show real potential for utilization in photodetectors, solar cells, and light-emitting diodes, achieving efficiencies and performance levels that are close to or exceed those of traditional semiconductors. However, the adoption of lead-based perovskites is limited by toxicity concerns in the field of solar cell applications (Hasan et al., 2023). The effects associated with lead-based perovskite have caused immense worry due to the severe environmental contamination it can cause, posing risks to human well-being and environmental sustainability (Ravi et al., 2020).

To address these concerns and move towards more sustainable alternatives, extensive research has shifted towards developing lead-free, nontoxic, and eco-friendly substitutes. These lead-free materials retain the desirable structural and optoelectronic properties of traditional lead-based perovskites, but without the environmental hazards (López-Fernández et al., 2024; Pecunia et al., 2020) In recent years, studies have shown that lead-free perovskites with structure A₃BX₃ possess direct band gaps with outstanding optical absorption characteristics, making them suitable for application in solar cells and optoelectronics. Barman et al. (2023) studied the electronic, optical, and mechanical properties of Ba₃AsI₃ using Density functional Theory. Their investigations reveal that this compound is ideal for optoelectronic applications. DFT calculations were also performed by Harun-Or-Rashid et al. (2024) to investigate the properties of lead-free Mg₃SbX₃. They reported that the compounds have semiconducting behaviour with direct band gaps, making them suitable for solar cell applications. Other A₃BX₃ perovskites, such as Sr₃AsI₃, Ca₃PI₃, and Ca3AsI3, have been studied and reported to exhibit excellent optical and electronic properties (Apurba et al., 2024; Rahman et al., 2024). Notable characteristics of these perovskites include strong light absorption, good carrier diffusion lengths, and efficient charge transport.

Among the A₃BX₃ family, Ba₃AsCl₃ is a promising lead-free candidate due to the enhanced chemical stability typically associated with chloride-based perovskites and the favorable ionic radii of Ba and As for stabilizing the A₃BX₃ framework. Despite these advantages, the properties of Ba₃AsCl₃ remain largely unexplored with respect to a comprehensive first-principles analysis that explicitly incorporates Spin-orbit coupling. In this study, we investigate the structural, electronic, elastic, and mechanical properties of Ba₃AsCl₃ using first-principles calculations.

2.0 MATERIALS AND METHODS

First Principles computations utilizing density functional theory (DFT) were carried out using Quantum Espresso (Giannozzi et al., 2009) and Thermo PW to investigate the structural, elastic, mechanical and electronic properties of Ba₃AsCl₃. The exchange-correlation energy is determined using the Generalized Gradient Approximation (GGA) with the Perdew-Burke-Ernzerhof (PBE) functional, while the projected augmented wave (PAW) pseudopotential from the standard solid-state pseudopotential library (Dal Corso, 2014) is employed to treat the electron-ion core interactions. A Convergence test is performed by carrying out self-consistent field calculations with different cutoff energies and Monkhorst-Pack k-point grids. To ensure calculation accuracy, a Cutoff energy of 70 Ry and a 10×10×10 k-point grid are used to sample the Brillouin zone. For structural properties, we performed a full relaxation of atomic positions and unit-cell dimensions to obtain an optimized lattice constant. Electronic properties were calculated using the self-consistent field (SCF) method, followed by non-self-consistent calculations with a denser 20×20×20 k-point grid to obtain the band structure (with and without SOC), density of states, and partial density of states. Elastic constant calculation is carried out by applying a small deformation to relax the structure; the resulting stresses are analyzed to determine the elastic constant (Jamal et al., 2014). These elastic constants serve as the basis for determining several other elastic properties, as well as mechanical properties.

3.0 RESULTS AND DISCUSSION

3.1 Structural properties

In studying material properties, it is important to start with structural properties, as they serve as a basis for analyzing material characteristics. The structure Ba₃AsCl₃ is a cubic perovskite of the A₃MX₃ type, with space group Pm-3m. Each unit cell contains seven atoms: three Ba, one As, and three Cl (AL-Shomar et al., 2024; Barman et al., 2023; Harun-Or-Rashid et al., 2024). Fig 1 shows the crystal structure and the crystallographic directions of Ba₃AsCl₃. The lattice parameters of the perovskites calculated are shown in Table 1.

Table 1: Structural parameters of Ba₃AsCl₃

Fig. 1: Crystal structure and crystallographic direction of Ba₃AsCl₃.

The calculated lattice constant of Ba₃AsCl₃ is consistent with previous work. The value obtained in the absence of SOC is 6.26 Å, which differs by 0.25 Å, approximately 3.8% from the reported value of 6.51 (Feng & Zhang, 2021). After applying spin-orbit coupling (SOC), the calculated lattice parameter shows excellent consistency with a deviation of 0.02 Å, approximately 0.3%. This highlights the importance of SOC in predicting the lattice parameter of Ba₃AsCl₃.

3.2 Electronic properties

Electronic property calculations are crucial for understanding and predicting the optoelectronic properties of materials (Lawal et al., 2017). In this study, we conduct an in-depth analysis of the electronic properties of Ba₃AsCl₃. The electronic band structure, density of states, and projected density of states are the electronic properties calculated in this paper. An important concept in condensed matter physics for explaining various properties of materials is the band structure (Barman et al., 2023; Hummel, 2000). The electronic band structure of Ba₃AsCl₃ along high-symmetry points of the Brillouin zone is computed with and without the addition of spin-orbit coupling (SOC). This is done because of the significant atomic numbers of Ba, As and Cl. Fig. 2(a) and (b) illustrate the electronic band structure of Ba₃AsCl_3, both with and without consideration of SOC. The red-dashed line indicates the Fermi energy level, set to 0 eV on the energy scale. Based on our band structure calculations, the energy gap between the conduction band minimum and the valence band maximum occurred at the Γ point. This suggests that Ba₃AsCl₃ is a direct-band-gap semiconductor, with the band gap corresponding to the \(\Gamma \rightarrow \Gamma\) transition. These results align with earlier DFT studies. Semiconductors with a direct band gap hold great potential for use in solar cells and optoelectronic devices (Nematov, 2024). The energy gap is 0.976 eV in the absence of SOC and drops to 0.934 eV when SOC is included. The impact of SOC on the conduction and valence band regions was significant, leading to shifts in the position of the CBM, as illustrated in Fig. 2 (a) and (b). The CBM shifted downward toward the Fermi level. The variation in the band gap between the two approaches is due to SOC-induced hybridisation.

Fig.2: Band structure of Ba₃AsCl₃ (a) without and (b) with SOC

To gain deeper insight into the band-gap characteristics of Ba3AsCl3, we studied the total and projected density of states (DOS and PDOS). Fig. 3(a) and (b) display the DOS and the PDOS, respectively. The DOS provides a more comprehensive understanding of the electronic characteristics of materials. It outlines how the energy states of electrons are distributed in a material, showing the number of electronic phases per unit energy that electrons can occupy. Conversely, all atoms contribution to the total DOS at the Fermi level is minimal compared to the valence and conduction bands. The PDOS provides a clearer understanding of how different atoms contribute to the electronic behaviour of materials. On the other hand, it illustrates how individual atoms and their orbital contributions affect the material's band gap energy (Shanto et al., 2023). The PDOS distribution for Ba₃AsCl₃ is shown in Fig. 3(b). The conduction band energy ranges from 0-5eV, with Ba-s, As-s and Cl-s having the most contribution in the conduction band. The Ba-p and Cl-p contribute to the electronic structure of the valence band, while As-p contribution is toward the Fermi level.

Fig.3: (a) Density of states (DOS), (b) PDOS for Ba₃AsCl₃

3.3 Elastic Properties

Elastic properties provide insight into how atoms are bonded and how the material responds to mechanical forces, such as stretching and compression. The elastic constants obtained are shown in Table 2. To ensure that a material is mechanically stable, it must satisfy the Born-Huang criteria defined by the equations below (Jamal et al., 2014).

\[C_{11} > 0\]

\[{2C}_{12}\ + C_{11} > 0\]

\(- C_{12} + C_{11} > 0\)

\[C_{44} > 0\]

\(C_{12} =\) \(C_{13} =\) \(C_{21} = C_{23} =\) \(C_{31} =\) \(C_{32}\)

The calculated elastic constants C_ij meet the Born-Huang criteria, indicating that Ba₃AsCl₃ is mechanically stable.

Table 2: The calculated elastic constants Cij (GPa), resistance to shear deformation by shear stress C’ (GPa), Cauchy pressure C” (GPa), and Kleinman’s parameter (ζ)

The parameters are calculated using the equations below (Naher & Naqib, 2021; Sahafi et al., 2024).

\[C' = \frac{- C_{12} + C_{11}}{2}\]

\[C^{''} = - C_{14} + C_{11}\]

\[\xi = \frac{8C_{12} + C_{11}}{2C_{12} + {7C}_{11}}\]

They measure the crystal’s stiffness, brittleness, or ductility and bond resistance to stretching and bending. The calculated Cauchy pressure is negative, which indicates the brittleness of Ba₃AsCl₃. The value of calculated Kleiman’s parameter is closer to 0 than 1, which indicates that the mechanical strength in Ba₃AsCl₃ is influenced by bond stretching contribution over bond bending.

3.4 Mechanical Properties

The mechanical properties, such as Young modulus, Shear modulus, Poisson ratio and Bulk modulus, are obtained from calculated elastic constants using the Voigt-Reuss-Hill approximation given by the equations below (Hao et al., 2024; Sahafi et al., 2024).

\[B_{H} = \frac{- B_{R} + B_{V}}{2}\ \ \]

\[G_{H} = \frac{- G_{R} + G_{V}}{2}\]

\[Y_{H} = \frac{9GB}{(G + 3B)}\]

\[v = \frac{3B - 2G}{2(G + 3B)}\]

The bulk modulus of materials is used to estimate the hardness and the resistance to compression. Materials with high bulk modulus are harder and more resistant to compression. Young's modulus measures a material's stiffness, that is, how it stretches or compresses under uniaxial stress, and the shear modulus measures a material's resistance to deformation. The findings suggest that Ba₃AsCl₃ has moderate values for all the moduli calculated (Shear, Young and Bulk), highlighting its potential for application in flexible optoelectronics. Poisson's ratio is another parameter that indicates a material's brittleness and ductility.

Table 3: Calculated Young modulus Y, Shear modulus G, Poisson ratio v, Bulk modulus B, Hardness H, Machinability index μm and Anisotropic factor A

Other mechanical properties, such as hardness H, machinability index μm, and anisotropic factor A, are calculated using the equations below.

\[H = \frac{(1 - 2v)Y}{6(1 + v)}\]

\[\text{μm} = \frac{B}{C_{44}}\]

\[A = \frac{{2C}_{44}}{C_{11} - C_{12}}\]

A material’s capacity to resist permanent deformation is influenced by its hardness. Machinability index refers to how easily a material can be cut, shaped or processed using machine tools. Materials with a high machinability index can be processed easily, whereas those with a low machinability index are harder to machine and require more time and effort (Sarker et al., 2024, 2025). Anisotropy index is a measure of how a material's elastic properties vary with direction. A value of 1shows an isotropic nature and deviation from this value shows anisotropy. Ba₃AsCl₃ is moderately hard, has a high machinability index and is anisotropic in nature. The computed mechanical properties are in reasonable agreement with previously reported values for similar A₃BX₃ compounds, indicating similar trends in mechanical stability across the family. In this work, we present a comprehensive first-principles study of Ba₃AsCl₃, in which spin–orbit coupling is explicitly incorporated, revealing its role in determining the structural properties and electronic characteristics, and highlighting its potential for optoelectronic and photovoltaic applications

CONCLUSION

In this study, we investigated the Structural, electronic, elastic, and mechanical characteristics of Ba₃AsCl₃ using density functional theory. The Structural investigation shows that Ba₃AsCl₃ has a stable cubic structure. The electronic study reveals that Ba₃AsCl₃ exhibits a direct band gap of 0.976eV when SOC is not included and 0.934eV when SOC is included, making it a semiconductor. The mechanical properties investigation suggests that Ba₃AsCl₃ is mechanically stable, anisotropic, and slightly brittle in nature. It also has a high machinability index. Overall, our findings indicate that Ba₃AsCl₃ perovskite is mechanically stable with a suitable bandgap and favourable electronic characteristics. Although optical properties are not covered here, the material's direct bandgap suggests potential for efficient optoelectronic and solar cell applications.

ACKNOWLEDGEMENT

The authors acknowledge TETFund through Umaru Musa Yar'adua University, Katsina (UMYUK), Katsina State, Nigeria, for financial support on this research work.

REFERENCES

Al-Shomar, S. M., Liaqat, M., Anmol, I., Quraishi, A. M., Khan, I., Amina, Arshad, K., Turdialiyev, U., Almahri, A., Tirth, V., Algahtani, A., Alsuhaibani, A. M., Abdullah, Refat, M. S., & Zaman, A. (2024). Study of structural, electronic, mechanical, optical and thermoelectric properties of As based halide-perovskites Ba3AsX3 (X= F, Cl): A first-principles insights. Journal of Materials Research and Technology, 31, 2450–2460. [Crossref]

Apurba, I. K. G. G., Islam, M. R., Rahman, M. S., Rahman, M. F., & Park, J. (2024). Tuning the physical properties of inorganic novel perovskite materials Ca3PX3 (X=I, Br and Cl): Density function theory. Heliyon, 10(7). [Crossref]

Barman, P., Rahman, M. F., Islam, M. R., Hasan, M., Chowdhury, M., Hossain, M. K., Modak, J. K., Ezzine, S., & Amami, M. (2023). Lead-free novel perovskite Ba3AsI3: First-principles insights into its electrical, optical, and mechanical properties. Heliyon, 9(11). [Crossref]

Dal Corso, A. (2014). Pseudopotentials periodic table: From H to Pu. Computational Materials Science, 95, 337–350. [Crossref]

Feng, H.-J., & Zhang, Q. (2021). Predicting efficiencies >25% A3MX3 photovoltaic materials and Cu ion implantation modification. Applied Physics Letters, 118(11). [Crossref]

Gayen, D., Chatterjee, R., & Roy, S. (2024). A review on environmental impacts of renewable energy for sustainable development. International Journal of Environmental Science and Technology, 21(5), 5285–5310. [Crossref]

Giannozzi, P., Baroni, S., Bonini, N., Calandra, M., Car, R., Cavazzoni, C., Ceresoli, D., Chiarotti, G. L., Cococcioni, M., Dabo, I., Corso, A. D., Fabris, S., Fratesi, G., de Gironcoli, S., Gebauer, R., Gerstmann, U., Gougoussis, C., Kokalj, A., Lazzeri, M., … Wentzcovitch, R. M. (2009). Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials. Journal of Physics: Condensed Matter, 21(39), Article 395502. [Crossref]

Hao, G., Hou, H. J., Zhang, S. R., & Xie, L. H. (2024). Theoretical study on the elastic and thermodynamic properties of CdS. Chalcogenide Letters, 21(1), 39–51. [Crossref]

Harun-Or-Rashid, M., Ferdous Rahman, M., Monirul Islam, M., Mohammed, M. K. A., & Bani-Fwaz, M. Z. (2024). Insight into the structural, electronic, mechanical, and optical properties of Pb-free new inorganic perovskite Mg3SbX3 (X = I, Br, Cl, F) via first-principles analysis. Inorganic Chemistry Communications, 168. [Crossref]

Hasan, N., Hasan, M. M., Kabir, A., & Rashid, M. H. (2023). Theoretical study of the structural, electronic, mechanical, and optical of transition metal (mn, co, and ni) doped FrGeI3 perovskites. Results in Materials, 20. [Crossref]

Hummel, R. E. (2000). Electronic properties of materials (3rd ed.). Springer.

Jamal, M., Jalali Asadabadi, S., Ahmad, I., & Rahnamaye Aliabad, H. A. (2014). Elastic constants of cubic crystals. Computational Materials Science, 95, 592–599. [Crossref]

Lawal, A., Shaari, A., Ahmed, R., & Jarkoni, N. (2017). Sb2Te3 crystal a potential absorber material for broadband photodetector: A first-principles study. Results in Physics, 7, 2302–2310. [Crossref]

Lawal, A., Shaari, A., Taura, L. S., Radzwan, A., Idris, M. C., & Madugu, M. L. (2021). G0W0 plus BSE calculations of quasiparticle band structure and optical properties of nitrogen-doped antimony trisulfide for near infrared optoelectronic and solar cells application. Materials Science in Semiconductor Processing, 124, Article 105592. [Crossref]

López-Fernández, I., Valli, D., Wang, C. Y., Samanta, S., Okamoto, T., Huang, Y. T., Sun, K., Liu, Y., Chirvony, V. S., Patra, A., Zito, J., De Trizio, L., Gaur, D., Sun, H. T., Xia, Z., Li, X., Zeng, H., Mora-Seró, I., Pradhan, N., … Polavarapu, L. (2024). Lead-free halide perovskite materials and optoelectronic devices: Progress and prospective. Advanced Functional Materials, 34(6). [Crossref]

Naher, M. I., & Naqib, S. H. (2021). An ab-initio study on structural, elastic, electronic, bonding, thermal, and optical properties of topological Weyl semimetal TaX (X = P, As). Scientific Reports, 11(1). [Crossref]

Nematov, D. (2024). Analysis of the optical properties and electronic structure of semiconductors of the Cu2NiXS4 (X = Si, Ge, Sn) family as new promising materials for optoelectronic devices. Journal of Optics and Photonics Research, 1(2), 91–97. [Crossref]

Pecunia, V., Occhipinti, L. G., Chakraborty, A., Pan, Y., & Peng, Y. (2020). Lead-free halide perovskite photovoltaics: Challenges, open questions, and opportunities. APL Materials, 8(10). [Crossref]

Rahman, M. F., Rahman, M., Hossain, M. F., Islam, B., Al Ahmed, S. R., & Irfan, A. (2024). A numerical strategy for achieving efficiency exceeding 32% with a novel lead-free dual-absorber solar cell using Ca3SbI3 and Sr3SbI3 perovskites. Advanced Photonics Research. [Crossref]

Ravi, V. K., Mondal, B., Nawale, V. V., & Nag, A. (2020). Don’t let the lead out: New material chemistry approaches for sustainable lead halide perovskite solar cells. ACS Omega, 5(46), 29631–29641. [Crossref]

Sahafi, M. H., Cholaki, E., & Bashir, A. I. (2024). First-principles calculations to investigate phonon dispersion, mechanical, elastic anisotropy and thermodynamic properties of an actinide-pnictide ceramic at high pressures/temperatures. Results in Physics, 58. [Crossref]

Sarker, M. A., Hasan, M. M., Luna, S. A., Chowdhury, M. I. H., Talukder, M. R., Islam, M. R., & Ahmad, S. (2025). A DFT investigation of structural, electronic, optical, and mechanical properties of lead-free novel InGeX3 (X = Cl, Br, and I) perovskites for potential applications in multijunctional solar cells. Energy Science and Engineering, 13(6), 2757–2771. [Crossref]

Sarker, M. A., Hasan, M. M., Momin, M. A., Irfan, A., Islam, M. R., & Sharif, A. (2024). Band gap engineering in lead free halide cubic perovskites GaGeX3 (X = Cl, Br, and I) based on first-principles calculations. RSC Advances, 14(12), 9805–9818. [Crossref]

Shahzad, U. (2012). The need for renewable energy sources. ITEE Journal, 1(3), 16–18. [Link]

Shanto, M. A. B., Rahman, M. F., Islam, M. R., Ghosh, A., Azzouz-Rached, A., Albalawi, H., & Mahmood, Q. (2023). Investigating how the electronic and optical properties of a novel cubic inorganic halide perovskite, Sr3NI3 are affected by strain. F1000Research, 12, 1005. [Crossref]

Ukoba, K., Yoro, K. O., Eterigho-Ikelegbe, O., Ibegbulam, C., & Jen, T. C. (2024). Adaptation of solar energy in the Global South: Prospects, challenges and opportunities. Heliyon, 10(7). [Crossref]

Zhang, L., Mei, L., Wang, K., Lv, Y., Zhang, S., Lian, Y., Liu, X., Ma, Z., Xiao, G., Liu, Q., Zhai, S., Zhang, S., Liu, G., Yuan, L., Guo, B., Chen, Z., Wei, K., Liu, A., Yue, S., … Ding, L. (2023). Advances in the application of perovskite materials. Nano-Micro Letters, 15(1). [Crossref]