Enhancing the electrochemical performance of TiO2 based material using microwave air plasma treatment with an ECR cavity.

The microwave-based plasma treatment facility at the Central University of Punjab Bathinda (CUPB) based on 2.45 GHz has been used to investigate the impact on the electrochemical performance of TiO2. This was accomplished by treating a number of pellets of TiO2 sample material with microwave plasma at an input power of 80 W. The palette is subjected to microwave plasma treatment at 30-, 60-, 80-, and 100-s intervals. Many such characterization methods, including UV-visible spectroscopy, FTIR, XRD, and FESEM, have been applied to the study of the impact of plasma treatment on other physical and chemical properties in the context of untreated pellets. In the 80-s plasma treatment, the FTIR study showed that the (O-Ti-O) vibration band at 500-900 cm-1 was wider than other bands. The UV results showed that an 80-s plasma treatment decreased the sample's band gap by 37% and increased the amount of disordered, amorphous material in the sample that had not been treated. XRD studies show that a sample that was treated with plasma for 80 s has low crystallinity and a high disorder (amorphous) factor. The Nyquist plot showed that the electrochemical charge transfer resistance drops from 7 (not treated) to 4 after 80 s of plasma treatment. In a study of electrochemical performance, a sample that was treated with plasma for 80 s has a capacitance that is 35% higher than a sample that was not treated.

Reduced graphene oxide doped tellurium nanotubes for high performance supercapacitor.

Supercapacitors have been achieving great interest in energy storage systems for the past couple of decades. Such devices with superior performance, mainly, depending on the material architecture of the electrodes. We report on the preparation of Tellurium nanotubes (Te-tubes diameter ∼100 nm and length ∼700 nm), with variable doping of conducting network reduced graphene oxide (rGO) to fabricate high-performance electrode characteristics of rGO @ Te. The prepared material was characterized using XRD, FTIR, FESEM, and Raman spectroscopy techniques, including Brunauer-Emmett-Teller, Barrett-Joyner-Halenda measurements. FTIR study revealed that 15% rGO @ Te has a wide C-O vibration band at ∼ 1,100-1,300 cm-1, over other compositions. FESEM study shows the Te-tubes dispersion in rGO layers. The EDX study revealed that 15% of the composition has an optimistic concentration of C and O elements. In other compositions, either at lower/higher rGO concentration, an uneven count of C and O is observed. These support efficient charge dynamics to achieve superior ultra-capacitor characteristics, thereby achieving specific capacitance Csp 170 + F/g @ 10 mV/s in a symmetric configuration. The reported values are thirty times higher than pristine Te-tubes (∼5 F/g). This finding suggests that rGO @ Te is a promising candidate for supercapacitor.

High-resolution phylogenetic analysis of Endomicrobia reveals multiple acquisitions of endosymbiotic lineages by termite gut flagellates.

Bacteria of the class Endomicrobia form a deep-branching clade in the Elusimicrobia phylum. They are found almost exclusively in the intestinal tract of animals and are particularly abundant in many termites, where they reside as intracellular symbionts in the cellulolytic gut flagellates. Although small populations of putatively free-living lineages have been detected in faunated and flagellate-free hosts, the evolutionary origin of the endosymbionts is obscured by the limited amount of phylogenetic information provided by the 16S rRNA gene fragment amplified with Endomicrobia-specific primers. Here, we present a robust phylogenetic framework based on the near-full-length 16S-23S rRNA gene region of a diverse set of Endomicrobia from termites and cockroaches, which also allowed us to classify the shorter reads from previous studies. Our data revealed that endosymbionts arose independently at least four times from different free-living lineages, which were already present in ancestral cockroaches but became associated with their respective hosts long after the digestive symbiosis between termites and flagellates had been established. Pyrotag sequencing revealed that the proportion of putatively free-living lineages increased, when all flagellates and their symbionts were removed from the gut of lower termites by starvation, starch feeding or hyperbaric oxygen, but results varied between different methods.