Enhanced Photo-Catalytic Performance of Activated Carbon Fibers for Water Treatment

Harnessing the photocatalytic potential of bismuth ferrite-activated carbon nanocomposite (BFO-AC) for Staphylococcus aureus decontamination under visible light

In response to the escalating global issue of microbial contamination, this study introduces a breakthrough photocatalyst: bismuth ferrite-activated carbon (BFO-AC) for visible light-driven disinfection, specifically targeting the Gram-positive bacterium Staphylococcus aureus (S. aureus). Employing an ultrasonication method, we synthesized various BFO-AC ratios and subjected them to comprehensive characterization. Remarkably, the bismuth ferrite-activated carbon 1:1.5 ratio (BA 1:1.5) nanocomposite exhibited the narrowest band gap of 1.86 eV. Notably, BA (1:1.5) demonstrated an exceptional BET surface area of 862.99 m2/g, a remarkable improvement compared to pristine BFO with only 27.61 m2/g. Further investigation through FE-SEM unveiled the presence of BFO nanoparticles on the activated carbon surface. Crucially, the photocatalytic efficacy of BA (1:1.5) towards S. aureus reached its zenith, achieving complete inactivation in just 60 min. TEM analysis revealed severe damage and rupture of bacterial cells, affirming the potent disinfection capabilities of BA (1:1.5). This exceptional disinfection efficiency underscores the promising potential of BA (1:1.5) for the treatment of contaminated water sources. Importantly, our results underscore the enhanced photocatalytic performance with an increased content of activated carbon, suggesting a promising avenue for more effective microorganism inactivation.

Highly Efficient Self-Assembled Activated Carbon Cloth-Templated Photocatalyst for NADH Regeneration and Photocatalytic Reduction of 4-Nitro Benzyl Alcohol

This manuscript emphasizes how structural assembling can facilitate the generation of solar chemicals and the synthesis of fine chemicals under solar light, which is a challenging task via a photocatalytic pathway. Solar energy utilization for pollution prevention through the reduction of organic chemicals is one of the most challenging tasks. In this field, a metal-based photocatalyst is an optional technique but has some drawbacks, such as low efficiency, a toxic nature, poor yield of photocatalytic products, and it is expensive. A metal-free activated carbon cloth (ACC)–templated photocatalyst is an alternative path to minimize these drawbacks. Herein, we design the synthesis and development of a metal-free self-assembled eriochrome cyanine R (EC-R) based ACC photocatalyst (EC-R@ACC), which has a higher molar extinction coefficient and an appropriate optical band gap in the visible region. The EC-R@ACC photocatalyst functions in a highly effective manner for the photocatalytic reduction of 4-nitro benzyl alcohol (4-NBA) into 4-amino benzyl alcohol (4-ABA) with a yield of 96% in 12 h. The synthesized EC-R@ACC photocatalyst also regenerates reduced forms of nicotinamide adenine dinucleotide (NADH) cofactor with a yield of 76.9% in 2 h. The calculated turnover number (TON) of the EC-R@ACC photocatalyst for the reduction of 4-nitrobenzyl alcohol is 1.769 × 1019 molecules. The present research sets a new benchmark example in the area of organic transformation and artificial photocatalysis.

Synthesis of enhanced corrosion resistant Fe-B-C-Ti amorphous ribbons and evaluation of their photodegradation efficiency under light irradiation

Fe-based amorphous alloys have been found to be very efficient in the degradation of water pollutants due to their unique atomic arrangements with long-range disordered structure. In this work, Fe-B-C-Ti amorphous ribbons were successfully synthesized and showed high catalytic efficiency in the degradation of methylene blue (MB) under simulated sunlight and across a wide pH range. The catalytic efficiency was evaluated under different conditions to optimize the degradation performance. The amorphous ribbon Fe₇₅B₁₀C₁₀Ti₅ was found to exhibit the highest photocatalytic activity as explained by its optical and photoelectrochemical properties. It can degrade MB completely with low Fe-leaching and significant recyclability at pH close to a neutral range (pH 5). The degradation mechanisms can be explained in terms of photocatalytic activity along with the galvanic cell effect which contributed to the efficient MB degradation. This work provides a comprehensive idea for the synthesis of amorphous alloys by optimizing their elemental composition and also explains the catalytic activity of partially crystallized regions on the ribbon surface. The significant corrosion resistance and the quick degradation of MB in a wide pH range in a recyclable manner by these easily separable and highly efficient catalysts indicate great potential for their practical application.

A novel robust adsorbent for efficient oil/water separation: Magnetic carbon nanospheres/graphene composite aerogel

Recently, graphene aerogels (GAs) have attracted considerable research attention in oil/water separation owing to their remarkable properties. However, the serious stacking of graphene oxide nanosheets (GO) would lead to low adsorption capacity and poor recyclability. For the first time, with alkaline ammonium citrate as reducing agent and nitrogen source, the point-to-face contact between magnetic carbon nanospheres (MCNS) and graphene sheets was adopted to effectively inhibit the aggregation of graphene sheets. Nitrogen-doped magnetic carbon nanospheres/graphene composite aerogels (MCNS/NGA) were fabricated under weakly alkaline conditions by one-step hydrothermal in-situ electrostatic self-assembling strategy. The aerogels have low density, super-elasticity (up to 95 % compression), high specific surface area (787.92 m² g^-1) and good magnetic properties. Therefore, they exhibit adsorption capacity in the range of 187-537 g g^-1 towards various organic solvents and oils, superior to most reported materials to date. In addition, thanks to their good mechanical properties, excellent thermal stability and flame retardancy, they can be regenerated by squeezing, distillation and combustion. More importantly, magnetic control technology can be adopted to realize oriented adsorption and facilitate recycling of organic solvents and oils in extreme environments.