AgBiS 2 is a promising and environmentally friendly absorber material for use in hybrid solar cells (HSC). Here, we report a study on the evolution of interfacial phenomena observed during deposition of AgBiS 2 onto mesoporous TiO 2 by the twostage successive ionic layer adsorptionreaction method. With this approach, inorganic-organic HSC were assembled using Co 2+ doped P3HT as hole transport layer. Surface photovoltage spectroscopy and contact potential difference measurements corroborated a low density of trap states in the ternary chalcogenide and lack of majority carrier barriers, compared to the binary absorbers used as reference. The best HSC exhibits a power conversion efficiency of 2.87% under irradiation of 100 mW cm −2 , which is attractive for an easily scalable, no capping, no passivating synthesis of AgBiS 2 .

In the present work, we report the preparation by the electrospinning technique and the characterization of poly(3hexylthiophene)-polyethylene oxide-single wall carbon nanotubes (P3HT-PEO-SWCNT) fibers. The SWCNT concentration into the P3HT-PEO matrix is varied from 0.2 to 1%. Optical, electrical, thermal, and morphological properties of the P3HT-PEO-SWCNT fibers are determined. The incorporation of the SWCNT into the P3HT-PEO polymer matrix is determined by SEM, EDS analysis, TEM, FTIR, and Raman. The optical properties are analyzed by the determination of photoluminescence and photoresponse. The stability and degradation temperature of the fibers are determined by TGA. The morphology of the P3HT-PEO-SWCNT fibers depends on the SWCNT concentration, in all cases non-beaded fibers are obtained. It is found that the SWCNT incorporating into the P3HT-PEO fibers increases the conjugation length of P3HT chains. Charge transfer from P3HT to SWCNT is corroborated by photoluminescence and Raman. The P3HT-PEO-SWCNT fibers obtained in this work exhibit interesting optoelectronic properties that could be useful for device applications.

Flat mixed matrix membranes (MMMs) comprising polysulfone and clinoptilolite-type natural zeolite were prepared by casting. Zeolite was modified with three alkylamines: ethanolamine (EA), bis(2-hydroxypropyl)amine (BHPA), and polyethylenimine (PEI) by the impregnation method. Impregnated zeolite samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and N 2 adsorption-desorption. The alkylamine loading extent determined by thermogravimetric analysis was 5.2, 4.8, and 8.5% for EA, BHPA, and PEI, respectively. Analyses of MMMs showed that the incorporation of impregnated zeolite affected the glasstransition temperature (T g ) and mixed-gas transport properties. In this regard, a decreasing trend of the T g values from 185.5 C for the polymeric membrane up to 176.6 C for Clino-EA-based MMM was recorded. In addition, the gas separation performance was evaluated at two different feed pressures. At 50 psi, MMMs showed an enhancement up to 30% on the CO 2 permeability (22.79 Barrer) and 55% on the CO 2 /CH 4 selectivity (45.78) in comparison with the polymeric membrane (CO 2 permeability 17.34 Barrer; CO 2 /CH 4 selectivity 29.38). These values varied depending on the alkylamine, BHPA being the most selective.

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In the present work, multiple-wall carbon nanotubes (MWCNTs) were surface modified in an environmentally friendly way, using low-frequency ultrasonic energy. This type of modification was carried-out using two different types of organic acids, citric acid (CA) and oxalic acid (OA). The modification of the MWCNTs was confirmed by Fourier-transform infrared spectroscopy (FTIR), where functional groups such as OH, C=O, O–C=O and COOH were detected. By means of Raman spectroscopy, an increase in carbon surface defects was found. On the other hand, using X-ray photoelectron spectroscopy (XPS), oxidation was evidenced on the surface of the modified MWCNT. In both Raman spectroscopy and XPS, the results indicate a greater modification when CA is used, possibly due to the fact that CA has a larger number of functional groups. MWCNT-CA showed good dispersion in methanol, while MWCNT-OA showed good stability in methanol and ethanol. Finally, a 20% removal of creatinine efficiency improvement was found with respect to the unmodified MWCNTs, while no improvement was found in the case of urea and uric acid.