This work presents for the first time a CdCO₃/CdO/Co₃O₄@nickel foam based supercapacitor with high both specific capacitance and energy density, a widespread potential window and a long cycle life.

[Eu(³DPIQC)₃] (where DPIQC = 3-(diphenyl phosphoryl)-1-isoquinolinecarboxylate), a luminescent europium complex with antenna ligands, has been carefully embedded within a polyvinyl butyral (PVB) matrix and the resulting material was used to prepare films used as luminescent down-shifting layers (LDSLs) for crystalline Si-based solar cells. The films were characterized using photoluminescence spectroscopy, atomic force spectroscopy (AFM), UV-Vis spectroscopy, and fluorescence microscopy. The AFM analysis shows films with low surface roughness, while fluorescence microscopy revealed that the Eu complex embedded in PVB assumed a spheroidal configuration, a morphology especially beneficial for optical applications. The so-obtained LDSLs were utilized as energy converters in c-Si solar cells to enhance the utilization of high-energy photons, thereby improving their overall efficiency. The determination of photovoltaic parameters carried out before and after the deposition of the LDSLs on the c-Si cells confirms a positive effect on the efficiency of the cell. The J_sc increases from 121.6 mA/cm² to 124.9 mA/cm², and the open circuit voltage (V_oc) is found to be unrelated to the complex concentration in the films. The fill factor (FF) remains constant with the Eu concentration. The EQE curves indicate an enhancement in the performance of the photovoltaic cells within the UV region of the spectrum for all coated devices. Electrochemical impedance spectroscopy (EIS) was also carried out in order to analyze the effect of the Eu complex in the charge transfer process of the devices.

Approximately 4% of women of reproductive age are estimated to suffer from premenstrual dysphoric disorder (PMDD), a condition likely underdiagnosed due to various biases, suggesting that actual prevalence may be higher. Addressing this, a novel electrochemical sensor was developed using a screen-printed electrode of reduced graphene oxide modified with a Cu(II) triazole complex, Cu(L^NO2)₂/rGO/SPCE. This sensor aims to determine levels of serotonin and 17β-estradiol rapidly, and simultaneously, key analytes implicated in PMDD. The method demonstrated high sensitivity for both analytes, achieving sensitivity levels of 0.064 μA/μmol L⁻¹ for serotonin and 0.055 μA/μmol L⁻¹ for 17β-estradiol, with a linear detection range of 2 to 42 μmol L⁻¹. Detection limits were 42 nmol L⁻¹ for serotonin and 53 nmol L⁻¹ for estrogen. The sensor also exhibited high stability and selectivity against common interferents found in biological fluids. It was successfully used to measure serotonin and 17β-estradiol in human serum and urine, with recovery percentages within the expected ranges. This demonstrates that the sensor proposed in this work holds significant potential to contribute not only to the accurate diagnosis of such disorders but also to their treatment. We hope that this research will pave the way for the development of devices that have a positive impact on the quality of life of women suffering from multisystem diseases caused by hormonal malfunctions.

This article focuses on the synthesis and characterization of an amorphous carbon derived from spent coffee grounds converted into a porous amorphous carbon (Cp₁) by carbonization up to 900 °C and subsequently combined with aluminum via mechanochemical treatment to obtain the composite Al@Cp₁. Powder X-Ray diffraction, Raman spectroscopy, and X-Ray photoelectron spectroscopy indicate turbostratic carbon domains (ID/IG ≈ 1.04) and an Al–O/Al–OH surface layer (Al₂O₃/Al(OH)₃) with a minor metallic Al contribution. Electrochemical performance in Li half-cells was evaluated by cyclic voltammetry, galvanostatic cycling, rate capability tests, and electrochemical impedance spectroscopy. At 0.02 A g⁻¹, Al@Cp₁ delivers 212.1 mAh g⁻¹, compared with 83.0 mAh g⁻¹ for Cp₁, with an initial coulombic efficiency of ~44%. Across increasing current densities, Al@Cp₁ retains higher reversible capacities than Cp₁ and shows stable cycling over extended tests (>160 cycles). Impedance analysis indicates a reduced interfacial/charge transfer resistance after electrode conditioning, consistent with interfacial stabilization by the Al-containing surface layer. These results demonstrate a simple, scalable route to upgrade coffee waste carbon into a higher-performance lithium-ion battery anode through mechanochemical interfacial engineering.