Toxicity and chemical instability issues of halide perovskites based on organic-inorganic lead-containing materials still remain as the main drawbacks for perovskite solar cells (PSCs). Herein, we discuss the preparation of copper (Cu)-based hybrid materials, where we replace lead (Pb) with nontoxic Cu metal for lead-free PSCs, and investigate their potential toward solar cell applications based on experimental and theoretical studies. The formation of (CHNH)CuX [(CHNH)CuCl, (CHNH)CuClI, and (CHNH)CuClBr] was discussed in details. Furthermore, it was found that chlorine (Cl) in the structure is critical for the stabilization of the formed compounds. Cu-based perovskite-like materials showed attractive absorbance features extended to the near-infrared range, with appropriate band gaps. Green photoluminescence of these materials was obtained because of Cu ions. The power conversion efficiency was measured experimentally and estimated theoretically for different architectures of solar cell devices.

No abstract

Generally, nanoparticles of CH 3 NH 3 PbI 3 (MLI) powders are increasingly recognized for their applications in solar cells. In this article, a new substitutional path to efficient mass yield with crucial reaction rates was proposed for the synthesis of MLI using a ball milling technique. We compare between the condensation reflux strategy (RM) and the ball milling (BM) technique as synthetic routes to produce microparticles (RM-MLI) and nanoparticles (BM-MLI) from MLI microcrystalline powder. The change in crystal structures, microstructure, and optical characteristics was investigated using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and photoluminescence emission (PL). FESEM micrographs showed a plummet straight down in particle size from 10 μm to ∼30 nm. The nanorods morphology was elucidated with transmission electron microscope (TEM). Optical absorption measurements indicate that compounds behaved with the characteristic of direct band gap with E g recorded at 1.50 and 1.56 eV for RM-MLI and BM-MLI, respectively. The two samples exhibited an intense near-IR photoluminescence (PL) emission in the 700−800 nm range at room temperature. The Hall effect was displayed as p-type semiconductors resulting from the positive sign of the Hall coefficient. Typically, with Cu 2 ZnSnS 4 (CZTS) as a hole transport material, the perovskite-sensitized TiO 2 film showed power conversion efficiencies (PCE) of 7.33 and 9.63% with fill factor records of 0.61 and 0.66 for RM-MLI and BM-MLI, respectively. Meanwhile, the results gave a maximum external quantum efficiency (EQE) of 65% at 530 nm at AM 1.5G 1 sun intensity (100 mW cm 2 ). Overall, this work gives an exceptionally simple, efficient methodology to synthesize MLI nanoparticles with efficient power conversion.

No abstract

No abstract

No abstract

Generally, strontium-doped lanthanum manganites (LSM) are materials connected ordinarily as cathodes in the solid oxide fuel cell (SOFC). In this study, the structural, optical, electrical and magnetic properties of LaSrMnO (x = 0.2, 0.5, 0.8) synthesized using an organic acid precursor strategy were investigated, based on using citric acid as a fuel. Evidently, the results disclosed that a pure single monoclinic LSM phase was obtained from the thermally treated precursors annealed at 1000 °C with an annealing time of 2 h. The microstructure of the formed sample relied on the Sr ion content. Moreover, a good optical transparency of 45-60% in a wide range of wavelengths between 800 and 1800 nm for all samples substituted by Sr ions was performed. The optical band gap energy was increased from 2.09 to 2.76 eV by increasing the Sr ion molar ratios. The trend in the calculated refractive index, the high frequency dielectric constant (ε) and the static dielectric constant (ε) of all the produced samples can be linked to an increase in the Sr ion concentration. Moreover, the magnetic properties were enhanced with increasing Sr ion content.

No abstract