Structural, Electronic, Magnetic, and Thermoelectric Properties of Cr-doped DPs Cs2GeX6 (X= Cl, Br): DFT calculations

2026-07-01T08:42:07+05:00

Physical properties of chromium-doped halide double perovskites (DPs) Cs₂GeX₆ (X= Cl, Br) are estimated with respect to the DFT-based software Wein2k. These materials can be selected for solar cells and photovoltaics owing to their non-toxicity and ecological sustainability. Density functional theory (DFT) calculations investigate the physical characteristics of halides A₂BX₆ (A=Cs; B=Ge; X=Cl, Br), both pure and Cr-doped, which can potentially be applied to thermoelectric applications. Formation conditions and tolerance factors ensure the material's structural and thermodynamic feasibility. The band gap of the material Cs₂GeCl₆ is 4.5 eV; the same for the doped one Cs₂Ge_0.75Cr_0.25Cl₆ is 4.1 eV; the band gap of the material Cs₂GeBr₆ is 3.0 eV, while that of the doped material Cs₂Ge_0.75Cr_0.25Br₆ is 2.5 eV. Cs₂Ge_0.75Cr_0.25Cl₆ and Cs₂Ge_0.75Cr_0.25Br₆ have indirect band gaps, respectively. Furthermore, when the chromium doping ratio increases, so do the equilibrium lattice parameters of Cs₂GeCl₆ and Cs₂GeBr₆. Cs₂GeCl₆: 10.32 Å, Cs₂Ge_0.75Cr_0.25Cl₆: 10.55 Å, and Cs₂GeBr₆: 10.65 Å, Cs₂Ge_0.75Cr_0.25Br₆: 10.85 Å are the calculated lattice parameters. Both compounds have the same total magnetic moment values with 25% Cr doping for Cs₂Ge_0.75Cr_0.25Cl₆and Cs₂Ge_0.75Cr_0.25Br₆. As a result, all of the halides investigated are commonly employed in thermoelectric devices. Thermal conductivity, electrical conductivity, and the Seebeck coefficient are also used to investigate thermoelectric properties. The computed values for PF at 200 K are PF=1.90 and 1.85 , and PF=3.98 and 4.09 at 800 K are measured for Cs₂Ge_0.75Cr_0.25Cl₆and Cs₂Ge_0.75Cr_0.25Br₆, respectively, highlighting their importance in thermoelectric applications. The Seebeck coefficient value drops as temperature increases.

The Technology of Lithium-Ion Batteries: An Alternative and Future Option to Meet Pakistan’s Energy Demands

2026-10-20T09:35:52+05:00

Pakistan faces persistent challenges of electricity shortfalls, over-dependence on imported fuels, grid instability, and ever-increasing electricity demand. At the same time, the country has significant wind and solar energy potential. However, these sources are intermittent, and a stable supply requires efficient and reliable energy storage. This study uses a qualitative literature review and policy analysis to assess the potential of lithium-ion (Li-ion) battery energy storage systems (BESS) as an effective and future-oriented solution to meet the country’s energy needs. The article contributes to the literature on energy sustainability in Pakistan by linking Li-ion BESS to national energy needs, storage applications, implementation barriers, lessons from international experience, and supply-chain resilience options. The assessment draws on official Government of Pakistan statistics for FY2024-25 to compare electricity generation and consumption and to evaluate the applicability and utility of Li-ion BESS in the current scenario. The study is limited in scope, as it does not include techno-economic modeling or project-specific surveys; instead, it relies on reports from international organizations and peer-reviewed studies on Li-ion BESS, solar–wind– energy storage systems, and international experience. The analysis compares Li-ion BESS with alternative technologies, including pumped-hydro storage, flow batteries, and emerging sodium-ion batteries, and proposes a needs-based approach to implementing such systems in Pakistan, grounded in financial and technological suitability. The study also examines the experiences of China, the United States, and South Korea to show how these countries have integrated battery storage into their energy sectors. At present, Pakistan lacks the domestic industry to support Li-ion BESS deployment, leaving it dependent on international supply chains for batteries and their components. The study therefore recommends a strategic, needs-specific, and phased adoption of the technology. The findings suggest that Li-ion BESS is a promising solution for distributed solar-plus-storage, backup supply, and electric mobility; however, it is not a standalone solution to Pakistan’s energy challenges. Deployment should be guided by site-specific feasibility studies, grid readiness, affordability, life-cycle costs, and diversified supply-chain mechanisms.

The Nucleus

Structural, Electronic, Magnetic, and Thermoelectric Properties of Cr-doped DPs Cs2GeX6 (X= Cl, Br): DFT calculations

The Technology of Lithium-Ion Batteries: An Alternative and Future Option to Meet Pakistan’s Energy Demands