Photo-bioelectrochemical cell anodes enhanced with titanium oxide, carbon nanotubes and chlorophyll-based catalyst on different supporting materials

An important part of a photo-bioelectrochemical cell (PBEC) is the photo-biocatalyst substrate taken as anode. This study aims to explain the effect of CNT/TiO2/chlorophyll photocatalyst coated on the cellulose nanopaper (CNP) substrate on the PBEC performance and to compare the results with those obtained for the commercial indium tin oxide (ITO) glass and flexible ITO as substrates. The results showed high sheet resistance of CNP, which is 61182 Ω sq-1, which is reduced by 80 % in the presence of CNT/TiO2/Chl biocatalyst. The highest output voltage of 0.95 to 1 V was produced by coating CNT/TiO2/Chl on the flexible ITO. The maximum current density (Jmax) of 3726 mA m-2 and the highest maximum power density value of around 574 mW m-2 were obtained for illuminated CNT/TiO2/Chl on the rigid ITO anode. In dark conditions, the highest power density was observed for CNP as the supporting substrate. The photo-bioelectrochemical cell adopting CNT/TiO2/Chl and CNP as the supporting substrate material has great potential for a variety of applications, such as wearable electronics, environmental monitoring, remote or off-grid energy supply, and renewable energy systems, thereby contributing to the advancement of sustainable energy technologies.

Eco-Friendly Chitosan-Based Biodiesel Heterogeneous Catalyst Support Membrane

A chitosan-polyvinyl pyrrolidone K-30 (Cs-PVP.K30) membrane was prepared as a heterogeneous catalyst supporting membrane in the transesterification process in the production of biodiesel from palm oil and methanol through the blend reaction between chitosan (Cs) and polyvinyl pyrrolidone K-30 polymer (PVP K-30). Several membranes were characterized by their physicochemical and catalytic properties. Based on physicochemical data, it was found that including the carbonyl group from PVP K-30 into the chitosan framework correlated with an increase in porosity, hydrophilicity, water absorption, and the degree of swelling of the membrane. The results of the analysis using Fourier Transmittance Infra-red (FTIR) showed the spectra of carbonyl (-C=O) and hydroxyl (-OH) groups at wavenumbers 1648 cm-1 and 3363 cm-1, which shows that the reaction of chitosan alloy with PVP K-30 has been successfully carried out. The catalytic site of the Cs-PVP K30-NaOH membrane in the biodiesel production process was studied under several conversion conditions. It was found that the conversion of biodiesel reached 93.90% with a reaction time of 90 minutes, a temperature of 65°C, and an oil/methanol mole ratio of 1:7