In situ carbothermal synthesis of carbonized bacterial cellulose embedded with nano zero-valent iron for removal of Cr(VI).

Carbonized bacterial cellulose embedded with highly dispersed nano zero-valent iron (nZVI), denoted as nZVI@CBC, was prepared through one-step in situ carbothermal treatment of bacterial cellulose adsorbing iron(III) nitrate. The structure characteristics of nZVI@CBC and its performance in removing hexavalent chromium Cr(VI) were investigated. Results showed the formation of nZVI@CBC with a surface area of 409.61 m2/g at 800 °C, with nZVI particles of mean size 28.2 nm well distributed within the fibrous network of CBC. The stability of nZVI was enhanced by its carbon coating, despite some inevitable oxidation of exposed nZVI. Batch experiments demonstrated that nZVI@CBC exhibited superior removal efficiency compared to bare nZVI and CBC. Under optimal conditions, nZVI@CBC exhibited a high Cr(VI) adsorption capacity of up to 372.42 mg/g. Therefore, nZVI@CBC shows promise as an effective adsorbent for remediating Cr(VI) pollution in water.

Nickel-decorated RuO2 nanocrystals with rich oxygen vacancies for high-efficiency overall water splitting.

Designing transition metal-oxide-based bifunctional electrocatalysts with excellent activity and stability for OER/HER to achieve efficient water splitting is of great importance for renewable energy technologies. Herein, a highly efficient bifunctional catalysts with oxygen-rich vacancies of nickel-decorated RuO2 (NiRuO2-x) prepared by a unique one-pot glucose-blowing approach were investigated. Remarkably, the NiRuO2-x catalysts exhibited excellent HER and OER activity at 10 mA cm-2 in alkaline solution with only a minimum overpotential of 51 mV and 245 mV, respectively. Furthermore, the NiRuO2-x overall water splitting exhibited an ultra-low voltage of 1.6 V to obtain 10 mA cm-2 and stability for more than 10 h. XPS measurement and theoretical calculations demonstrated that the introduction of Ni-dopant and oxygen vacancies make the d-band center to lie close to the Fermi energy level, the chemical bonds between the active site and the adsorbed oxygen intermediate state are enhanced, thereby lowering the reaction activation barriers of HER and OER. The assembly of solar-driven alkaline electrolyzers facilitate the application of the NiRuO2-x bifunctional catalysts.

Gas assisted in situ biomimetic mineralization of bacterial cellulose/calcium carbonate bio composites by bacterial.

Biomineralization inspired process to produce polymer of desired need is a promising approach in the field of research. In the present work, the bacterial cellulose (BC) based nanocomposites with a 3D network were synthesized via a biological route by choosing the calcium salt of primary metabolites (calcium gluconate) as the carbon source. The BC based composites were characterized by employing with Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). During the preparation of nanocomposites, the calcium ions embedded on the cellulose fibrils were served as the nucleation center and calcium carbonate was deposited into BC network in the assistance of CO2. The uniform distribution of embedded objects on the cellulose nanofibers between internal and external was achieved. The exploitation of organisms for inorganic growth, shape and self-assembling explores new opportunities to the design of original nanostructures.