Two-dimensional MXenes have gained tremendous interest as frontier materials for a wide variety of applications and play a pivotal role in the development of future energy, electronic and optoelectronic devices as they exhibit high catalytic activity in diverse electrocatalytic and photocatalytic devices. The fabrication and application of MXenes as catalysts have become more progressive in recent years and more than 30 different varieties have been experimentally discovered and utilized. In this review, we rationally summarized and discussed the most recent advances in the synthesis and specific applications of MXenes as electrocatalysts and photocatalyst for hydrogen evolution reaction (HER) and CO2 reduction reaction (CO2RR) including strategies for boosting their catalytic activity for target products. Finally, we highlight the lingering challenges and direction for the future development of MXenes as catalysts …
This research designed a simplified, sensitive electro-chemical procedure to detect cabergoline by a means of a SPE modified with Fe2MoO6 magnetic nanocomposite (Fe2MoO6/SPE). Fe2MoO6 magnetic nano-composite has been procured through via a simplified procedure. According to the analyses, the final nanocomposite has been described by XRD, EDS, TEM, SEM and VSM analysis. The prepared modified electrode exhibited the greater peak currents to oxidize cabergoline than that of the unmodified SPE. The analytical curve for the determination of cabergoline had very good linear response in the range between 0.08-300.0 µM for cabergoline. The detection limit for determining cabergoline was 0.02 µM. Finally, our technique has been substantially utilized for detecting cabergoline in the real samples.
The impact of introducing nano-sized ZrO2 additive on the sinterability and microstructure development of ZrB2–SiC composite was studied. The spark plasma sintering (SPS) technique was selected as the manufacturing method, and the as-sintered sample reached a relative density value slightly higher than 98.5%. Advanced electron microscopy techniques along with X-ray diffraction (XRD) were used to characterize the final composite. The XRD assessment revealed the formation of two in-situ phases, namely ZrC and ZrSiO4, along with the initial phases. Thermodynamic evaluations suggested the possible formation of a liquid phase due to an interaction among the available oxides (e.g., ZrO2, SiO2, and B2O3). This assumption was fortified by the presence of an amorphous phase in the scanning electron microscopy (SEM) analysis. Finally, transmission electron microscopy (TEM) verified the formation of such …
Herein, we report a composite structure composed of vertically grown molybdenum disulfide (MoSx) nanosheets supported by conductive carbon nanotube–reduced graphene oxide (CNT–rGO) on Vietnamese traditional paper (MoSx/CNT–rGO/VTP) for a high-performance electrochemical hydrogen evolution reaction (HER). In the fabrication, CNT–rGO is first prepared on VTP by roll coating, following which the vertically aligned MoS2 nanosheets are synthesized on the surface of CNT–rGO/VTP through a simple hydrothermal reaction. The catalyst exhibits excellent HER electrocatalytic activity including a low onset potential of 190 mV, Tafel slope of 59 mV dec−1, and excellent stability in an acidic electrolyte solution. The excellent catalytic performance can be attributed to the abundant active edges provided by the vertically aligned MoSx nanosheets, as well as the effective electron transport provided by the CNT …
Biomass waste represents the promising surrogate of fossil fuels for energy recovery and valorization into value-added products. Among thermochemical conversion techniques of biomass, pyrolysis appears to be most alluring owing to its low pollutant emission and diverse products formation. The current pyrolysis applications for valorization of biomass waste is reviewed, covering the key concepts, pyrolysis mode, operating parameters and products. To date, existing types of pyrolysis include conventional pyrolysis (poor heat transfer due to non-selective heating), vacuum pyrolysis (lower process temperature because of vacuum), solar pyrolysis (entirely “green” with solar-powered), and a newly touted microwave pyrolysis. In microwave pyrolysis of biomass, the heat transfer is more efficient as the heat is generated within the core of material by the interaction of microwave with biomass. The plausible mechanisms …
TiO2 has gained tremendous attention as a cutting-edge material for application in photocatalysis. The performance of TiO2 as a photocatalyst depends on various parameters including morphology, surface area, and crystallinity. Although TiO2 has shown good catalytic activity in various catalysis systems, the performance of TiO2 as a photocatalyst is generally limited due to its low conductivity and a wide optical bandgap. Numerous different studies have been devoted to overcome these problems, showing significant improvement in photocatalytic performance. In this study, we summarize the recent progress in the utilization of TiO2 for the photocatalytic hydrogen evolution reaction (HER). Strategies for modulating the properties toward the high photocatalytic activity of TiO2 for HER including structural engineering, compositional engineering, and doping are highlighted and discussed. The advantages and limitations of each modification approach are reviewed. Finally, the remaining obstacles and perspective for the development of TiO2 as photocatalysts toward high efficient HER in the near future are also provided.
