Microbial fuel cells (MFC) can generate electric energy from wastewater which can be enhanced further by anode catalysts. The recovery of electrons produced by oxidation of organics catalyzed by bacteria in the anode was enhanced when carbon dots(CDs) were added into the MFC. In this present study, a novel strategy for designing anode material and the fabrication of a high-efficient and environmentally friendly anode for energy generation from wastewater was reported. The CDs were synthesized by the pyrolysis of a peanut shell at the temperature of 250 °C for 2 h with a heating rate of 10 °C min⁻¹. Thus synthesized CDs were characterized by transmission electron microscopy (TEM), UV/Vis spectroscopy, and fluorescence spectroscopy. The TEM analysis showed morphology with an average size of 1.62 nm. The UV/Vis absorbance of the CDs shows a wide absorption band without a characteristic peak. The excitation spectrum of CDs recorded at the emission wavelength of 440 nm exhibits a peak around 320 nm. CDs were investigated as an anode material in a MFC utilizing acetate as the organic substrate. The average chemical oxygen demand (COD) removal in closed circuit operation mode was 89%. The maximum power density production (7.2 W/m³) was observed in MFC containing 1 mg/cm² CD-impregnated anode (CDsIA). The CDsIA provides the ability to promote efficient biofilm formation. These results emphasize the application of CD-based electrodes in MFCs for the simultaneous treatment of wastewater and electricity generation while also providing additional benefits.

Reduced graphene oxide (rGO) and zinc oxide nanoparticles (ZnO NPs) were synthesized using modified Hummer's method and green approach from Carica papaya leaf extract (CPLE), respectively. ZnO NPs were then loaded onto rGO using a straightforward ultrasonic method to synthesize Zinc oxide-reduced graphene oxide nanocomposite (ZnO-rGO NC). Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), and X-ray diffraction (XRD) techniques were used to characterize the synthesized nanoparticles and composite respectively. The nanocomposite was used to remove Rhodamine B dye (RhB) from aqueous solution. The effects of temperature, pH, adsorbent dosage, initial dye concentration, and contact time were investigated. Testing was done on the Freundlich and Langmuir isotherm models as well and the thermodynamics parameters were computed. The effects of ZnO NPs, rGO, and ZnO-rGO NC independently on dye removal in a comparative analysis were carried out and resulteds were presented. In an aqueous medium, the nanocomposite demonstrated high removal efficiency as an adsorbent for removing RhB dye at 99% compared to ZnO NPs at 60%. ZnO-rGO NC proved to be an effective adsorbent compare to ZnO NPs.

Understanding DNA‒nanoparticle interactions is crucial in nanobiotechnology, enabling the design of DNA-based nanostructures for sensing, therapy and bioengineering applications. CDs have emerged a...