4 research outputs found
International Renewable and Sustainable Energy Conference IRSEC
A green and friendly synthesis method was used to prepare Anatase TiO2 and the electrochemical performances of this metal oxide as negative electrode for lithium ion batteries were studied. X-Ray diffraction analysis confirm the formation of Titanium Oxide with anatase type structure with a small content of brookite phase. The spherical shape of the particles is clearly highlighted using Scanning Electron Microscopy. The prepared TiO2 electrode delivers a discharge capacity of 290 mAh g(-1) in the first cycle under C/10 current rate. Indeed, a coulombic efficiency higher than 95 and a capacity retention of 85% is obtained after 100 cycles
Facile synthesis of nanoparticles titanium oxide as high-capacity and high-capability electrode for lithium-ion batteries
Anatase TiO2 is prepared via a facile and eco-friendly synthesis method where titanium tetra isopropoxide and sodium alginate are used as the titanium precursor and templating agent, respectively. Structural characterization of the prepared sample via X-ray diffraction and Raman spectroscopies confirm the formation of nanoparticles Titanium Oxide with anatase type structure without impurities. Further morphological characterization of the material showed the spherical shape of the particles. The prepared TiO2 has been studied as an anode material for lithium-ion batteries. TiO2 electrodes have delivered a reversible capacity of 266 mAh g(-1), 275 mAh g(-1) with coulombic efficiencies of 70%, 75% during the first cycle under C/10 current rate for TiO2 calcined at 300 degrees C and 450 degrees C, respectively. The activity of Ti4+/Ti3+ redox couple during the lithiation/delithiation process was evidenced using X-ray Photoelectron Spectrometry. The high capacity retention was maintained for 100 cycles. The prepared nanoparticles TiO2 has prodigious potential for large scale production of anode materials for lithium-ion batteries
The Electrochemical and Structural Changes of Phosphorus-Doped TiO 2 through In Situ Raman and In Situ X-Ray Diffraction Analysis
International audienceDoping is a widely employed technique to enhance the functionality of lithium-ion battery materials, tailoring their performance for specific applications. In our study, we employed in situ Raman and in situ X-ray diffraction (XRD) spectroscopic techniques to examine the structural alterations and electrochemical behavior of phosphorus-doped titanium dioxide (TiO2) nanoparticles. This investigation revealed several notable changes: an increase in structural defects, enhanced ionic and electronic conductivity, and a reduction in crystallite size. These alterations facilitated higher lithiation rates and led to the first observed appearance of LiTiO2 in the Raman spectra due to anatase lithiation, resulting in a reversible double-phase transition during the charging and discharging processes. Furthermore, doping with 2, 5, and 10 wt % phosphorus resulted in an initial increase in specific capacity compared to undoped TiO2. However, higher doping levels were associated with diminished capacity retention, pinpointing an optimal doping level for phosphorus. These results underscore the critical role of in situ characterization techniques in understanding doping effects, thereby advancing the performance of anode materials, particularly TiO2, in lithium-ion batteries
Hydrolysis of Hemicellulose and Derivatives—A Review of Recent Advances in the Production of Furfural
Biobased production of furfural has been known for decades. Nevertheless, bioeconomy and circular economy concepts is much more recent and has motivated a regain of interest of dedicated research to improve production modes and expand potential uses. Accordingly, this review paper aims essentially at outlining recent breakthroughs obtained in the field of furfural production from sugars and polysaccharides feedstocks. The review discusses advances obtained in major production pathways recently explored splitting in the following categories: (i) non-catalytic routes like use of critical solvents or hot water pretreatment, (ii) use of various homogeneous catalysts like mineral or organic acids, metal salts or ionic liquids, (iii) feedstock dehydration making use of various solid acid catalysts; (iv) feedstock dehydration making use of supported catalysts, (v) other heterogeneous catalytic routes. The paper also briefly overviews current understanding of furfural chemical synthesis and its underpinning mechanism as well as safety issues pertaining to the substance. Eventually, some remaining research topics are put in perspective for further optimization of biobased furfural production