Here a combined DFT, SCAPS-1D, and wxAMPS frameworks are used to investigate the optimized designs of Cs2BiAgI6 lead-free double perovskite-based solar cells from ninety-six device structures using various electron and hole charge transport layers.

Lead-free Cs2BiAgI6 has garnered a lot of research interest recently due to its suitability as a potential absorber layer in the solar cell (SC) architecture owing to its low cost, good stability, and high efficiency. The main highlight of this research work includes the photovoltaic (PV) performance enhancement of Cs2BiAgI6 double perovskite solar cells (PSCs) by optimizing the optoelectronic parameters of the absorber, electron transport layer (ETL), hole transport layer (HTL), and various interface layers. Solar Cell Capacitance Simulator One dimension (SCAPS-1D) numerical simulation was used to optimize the performance of Cs2BiAgI6 absorber-based SCs consisting of copper barium thiostannate (CBTS) as the HTL and TiO2, PCBM, ZnO, IGZO, SnO2, and WS2 as ETLs. The role of the non-lead cesium-based halide perovskite absorber layer in the improvement of the SC performance was systematically investigated through a variation in the thickness, doping density, and defect density of the absorber layer, ETL, and HTL. The performance of the investigated device architectures is largely dependent on the thickness of the absorber layer, acceptor density, defect density, and the combination of different ETLs and HTLs. We found that TiO2, PCBM, ZnO, IGZO, SnO2, and WS2 ETL-based optimized devices recorded a power conversion efficiency (PCE) of 23.14, 23.71, 23.69, 22.97, 23.61, and 21.72%, respectively. Furthermore, the effect of series and shunt resistances, temperature, capacitance, and Mott–Schottky for the six optimized devices was estimated along with the computation of the corresponding generation and recombination rates, current density–voltage (J–V), and quantum efficiency (QE) characteristics. The PV parameters obtained from this comprehensive analysis are finally compared with the earlier published theoretical and experimental reports on Cs2BiAgI6 absorber-based SCs.

Nontoxic and inorganic lead-free double perovskite La2NiMnO6 (LNMO) has achieved tremendous attention as an absorber layer of a solar cell (SC) structure due to its outstanding optoelectronic properties to support photovoltaic (PV) applications. In order to check the feasibility of LNMO as a potential SC absorber material, the structural, electronic, and optical properties of LNMO are computed within the realm of density functional theory (DFT). The computed energy band diagram confirms that LNMO is a degenerate semiconductor with an indirect band gap (E g) of ∼0.58 eV. In addition, the density of states (DOS) implies that the d-orbital electron of Mn and Ni elements and p-orbitals of O elements contributed significantly to the electronic conductivity of the material. The electronic charge density map and Mulliken population analyses manifest robust electronic charge accumulation around the O atom and the strong covalent bonding nature of Ni–O and Mn–O bonds, respectively. The strong absorption peaks in the infrared (20.0 eV), visible (2.6 eV), and near-ultra-violet (7 eV) regions reflect the true potential of LNMO as a PV material. Furthermore, the SCAPS-1D simulation tool is used to investigate the best-optimized electron transport layer (ETL)/LNMO/hole transport layer (HTL) SC configurations where PCBM, ZnO, C60, and WS2 are used as ETLs, while CuSCN, NiO, P3HT, PEDOT:PSS, ZnO, and CuSCN are used as HTLs. The WS2/LNMO/CFTS solar structure exhibited the best power conversion efficiency (PCE) of ∼20.18% among 24 different solar device combinations. The four best SC configurations are chosen for PV performance analysis through a variation in the ETL and absorber layer thicknesses. Furthermore, the impact of the variation of the series and shunt resistances of these SC structures are investigated. For deeper insights, the C–V plots, generation and recombination rates, J–V curves, and quantum efficiency plots are analyzed for the investigated configurations.

In the future, when fossil fuels are exhausted, alternative energy sources will be essential for everyday needs. Hydrogen-based energy can play a vital role in this aspect. This energy is green, clean, and renewable. Electrochemical hydrogen devices have been used extensively in nuclear power plants to manage hydrogen-based renewable fuel. Doped zirconate materials are commonly used as an electrolyte in these electrochemical devices. These materials have excellent physical stability and high proton transport numbers, which make them suitable for multiple applications. Doping enhances the physical and electronic properties of zirconate materials and makes them ideal for practical applications. This review highlights the applications of zirconate-based proton-conducting materials in electrochemical cells, particularly in tritium monitors, tritium recovery, hydrogen sensors, and hydrogen pump systems. The central section of this review summarizes recent investigations and provides a comprehensive insight into the various doping schemes, experimental setup, instrumentation, optimum operating conditions, morphology, composition, and performance of zirconate electrolyte materials. In addition, different challenges that are hindering zirconate materials from achieving their full potential in electrochemical hydrogen devices are discussed. Finally, this paper lays out a few pathways for aspirants who wish to undertake research in this field.

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