The highly successful PBE functional and the modified Becke–Johnson exchange potential were used to calculate the structural, electronic, and optical properties of the vacancy-ordered double perovskites A2BX6 (A = Rb, Cs; B = Sn, Pd, Pt; X = Cl, Br, and I) using the density functional theory, a first principles approach. The convex hull approach was used to check the thermodynamic stability of the compounds. The calculated parameters (lattice constants, band gap, and bond lengths) are in tune with the available experimental and theoretical results. The compounds, Rb2PdBr6 and Cs2PtI6, exhibit band gaps within the optimal range of 0.9–1.6 eV, required for the single-junction photovoltaic applications. The photovoltaic efficiency of the studied materials was assessed using the spectroscopic-limited-maximum-efficiency (SLME) metric as well as the optical properties. The ideal band gap, high dielectric constants, and optimum light absorption of these perovskites make them suitable for high performance single and multi-junction perovskite solar cells.

In the recent past, optoelectronic semiconductors have attracted significant research attention both experimentally and theoretically toward large-scale applications in energy conversion, lighting, imaging, detection, and so on. With advancement in computing power and rapid development of computational algorithms, scientific community resorts to materials simulation to explore the hidden potential behind thousands of potentially unknown materials within short timeframes that the real experiments might take a long time. Within this context, the high-throughput (HT) computational materials screening has emerged as a useful tool to accelerate materials discovery, especially in the field of optoelectronic semiconductors. One of the important consequences is the construction of a number of material databases containing wide range of functional materials with their diverse physical properties and applications. Herein, we reviewed the recent progress on HT computational screening of optoelectronic semiconductors, with focus on photovoltaic solar absorbers, photoelectrochemical cells, semiconductor light-emitting diodes, and transparent conducting materials. We have also summarized the general workflow of HT computational screening, released workhorse models, and existing material databases. Finally, we offer perspectives for future research with a hope that this study could inspire new ideas for computational-driven optoelectronic semiconductor discovery in the HT routine. This article is categorized under: Structure and Mechanism > Computational Materials Science K E Y W O R D S first principles calculations, high-throughput, materials by design, optoelectronic semiconductors 1 | INTRODUCTION The excessive use of fossil fuels has caused global energy crisis and environmental concerns at the current stage. 1 Finding and designing novel energy materials is the key to sustainable development of human society. 2-4 Additionally, the information and electronic devices are widely used in industrials, astronautic, environmental, medical, and biological fields. 5 Materials with low cost and superior electroluminescence performance are the metrics for the development of

Supercapacitors (SCs) are highly promising electrochemical energy conversion and storage devices. SCs display an outstanding power performance, excellent reversibility, long-term stability, simple operation, and high feasibility for integration into electronic devices, including consumer electronics, memory backup systems, and industrial power and energy management systems. The electrode materials determine the cell capacitance, operating voltage, power density, energy density, and time constant of SCs. Transition metal-based electrode materials (TMEMs) are among the most promising electrodes for SCs, due to their outstanding energy density, specific capacitance, and quick charging/discharging rates, in addition to their ease of preparation in a high yield from low-cost and earth-abundant resources. Binary transition metal sulfides (BTMSs) possess various advantages relative to other TMEMs, including higher storage capacity, higher electrical conductivity, excellent redox properties, better specific capacitance, quicker electron/ion diffusion, and superior reversibility with long cycle life. Herein, the inventory and the recent progress in the rational design of BTMS electrodes for SCs are deliberated, spaning from the preparation methods to the operative conditions, performance, and mechanism. To help assist in the further development of BTMS electrodes for efficient and durable SCs, current underlying challenges and possible solutions are identified and addressed, with emphasis on device performance vs BTMS type and relative merits.

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Summary Lead halide perovskites are considered as a material of choice for solar cell applications. However, there are challenges: organic cations in halide perovskites are unstable, and lead is toxic. To address these issues, we propose and investigate some potential alternatives to lead in the form of A2BX6 perovskites using the first‐principles calculations. Besides simple approximation potentials, we use a highly successful hybrid functional HSE06, to calculate the electronic, optical, and thermoelectric properties of A2PdI6 (A = K, Rb, and Cs). Our calculations show that K2PdI6, Rb2PdI6, and Cs2PdI6, are narrow bandgap semiconductors with bandgap of 0.8, 0.92, and 0.9 eV, respectively. The valence band maximum (VBM) of A2PdI6 is mainly composed of I‐5p orbitals while the conduction band minimum (CBM) is formed of Pd‐4d and I‐5p orbitals. Due to the ideal bandgap and excellent light absorption, Rb2PdI6 stands out as a potential candidate for usability in tandem solar cells. In addition, p‐type doping at a carrier concentration of 1 × 1018 cm−3 makes these perovskites a material of choice for thermoelectric energy applications.

We investigated double perovskite compounds of the form Sr 2 XOsO 6 (X = Li, Na, Ca) using the fullpotential linearized augmented plane wave (FP-LAPW) method. For the exchange-correlation energy, Wu and Cohen generalized gradient approximation (WC-GGA), Perdew, Burke and Ernzerhof GGA (PBE-GGA), Engel and Vosko GGA (EV-GGA), and GGA plus Hubbard U-parameter (GGA + U) were used. The calculated structural parameters are in good agreement with the existing experimental results. Calculation of different elastic constants and elastic moduli reveals that these compounds are elastically stable and possess ductile nature. The GGA + U approach yields quite accurate results of the bandgap as compared with the simple GGA schemes. The density of states plot shows that Sr-4d, Os-5d and O-2p states predominantly contribute to the conduction and valence bands. Further, our results regarding to the magnetic properties of these compounds reveal their ferromagnetic nature. In addition, these compounds seem to possess half-metallic properties, making them useful candidates for applications in spintronics devices.