Improving the absorption of visible light in photocatalysts could enhance photocatalytic reactions and reduce energy consumption, particularly in sunny regions like Ecuador. This study reports the synthesis of ZnO and ZnO nanoparticles doped with 1.5 at.% Er, 5 at.% Al, and 1.5 at.% Er, 5 at.% Al using the sol–gel method. The effect of doping on the structure, morphology, absorption spectra, and photocatalytic properties was analyzed by XRD, SEM, EDS, and UV-Vis spectrophotometry. XRD confirmed the presence of the wurtzite ZnO structure, and UV-Vis diffuse reflection spectra showed a red shift in the band gap for doped ZnO compared to pristine ZnO. Photocatalytic activity was evaluated through the degradation of methyl orange (MO) under artificial visible light and natural sunlight in Quito, Ecuador. ZnO doped with Er/Al nanoparticles exhibited significantly enhanced photocatalytic performance under solar light, suggesting the potential for replacing artificial light and reducing operating costs in photocatalytic processes. Moreover, all doped samples retained the antibacterial properties of ZnO against B. subtilis, and Er/Al co-doping improved the inhibition of E. coli compared to undoped ZnO.

Chitosan biopolymer membranes reinforced with channel-selective ZIF-8 nanofillers were developed and thoroughly characterized as separators for bioelectrochemical systems. This study explores the synergistic effect of incorporating ZIF-8 into a chitosan matrix to enhance membrane performance. Key properties including water retention, chemical and thermal stability, surface resistance, antifouling capacity, and ionic conductivity were evaluated and benchmarked against commercial Nafion-117 and nanofiltration (NF) membranes. The ZIF-8/chitosan composite membranes (ZIF-8/CS) demonstrated excellent water retention and structural stability under harsh conditions, along with significantly reduced surface resistance and effective rejection of organic contaminants and salts (NaCl, Na₂SO₄). Notably, the composite ZIF-8/CS membranes achieved an ionic conductivity of 0.099 S/cm, approaching the value of Nafion-117 (0.13 S/cm) and substantially surpassing that of the NF membrane (0.013 S/cm). These results indicate that ZIF-8-reinforced chitosan membranes present a promising, sustainable, and cost-effective alternative to traditional separators in bioelectrochemical applications.

Improving the absorption of visible light in photocatalysts could enhance photocatalytic reactions and reduce energy consumption, particularly in sunny regions like Ecuador. This study reports the synthesis of ZnO and ZnO nanoparticles doped with 1.5 at.% Er, 5 at.% Al, and 1.5 at.% Er:5 at.% Al using the sol-gel method. The effect of doping on the structure, morphology, absorption spectra, and photocatalytic properties was analyzed by XRD, SEM, EDS, and UV-Vis spectrophotometry. XRD confirmed the presence of the wurtzite ZnO structure, and UV-Vis diffuse reflection spectra showed a red-shift in the band-gap for doped ZnO compared to pristine ZnO. Photocatalytic activity was evaluated through the degradation of methyl orange (MO) under artificial visible light and natural sunlight in Quito, Ecuador. ZnO doped with Er/Al nanoparticles exhibited significantly enhanced photocatalytic performance under solar light, suggesting the potential for replacing artificial light and reducing operating costs in photocatalytic processes. Moreover, all doped samples retained the antibacterial properties of ZnO against B. subtilis, and Er/Al co-doping improved the inhibition of E. coli compared to undoped ZnO.