Hydrogen–nitrogen plasma assisted synthesis of titanium dioxide with enhanced performance as anode for sodium ion batteries

Abstract

Sodium ion batteries are considered as one of the most promising energy storage devices as lithium ion batteries due to the natural abundance of sodium. tio 2 is very popular as anode materials for both lithium and sodium ion batteries because of the nontoxicity, safety and great stabilities. However, the low electronic conductivities and inferior sodium ion diffusion make it becoming a great challenge to develop advanced tio 2 anodes. Doping heteroatoms and incorporation of defects are believed to be great ways to improve the electrochemical performance of tio 2 anodes. In this work, commercial tio 2 (P25) nanoparticles was modified by hydrogen and nitrogen high-power plasma resulting in a disordered surface layer formation and nitrogen doping as well. the electrochemical performances of the samples as anode materials for sodium ion batteries was measured and the results indicated that after the hydrogen-nitrogen plasma treatment, H-N-TiO 2 electrode shows a 43.5% of capacity higher than the P-TiO 2 after 400 cycles long-term discharge/charge process, and the samples show a good long cycling stability as well, the Coulombic efficiencies of all samples are nearly 99% after 50 cycles which could be sustained to the end of long cycling. in addition, hydrogen-nitrogen plasma treated tio 2 electrode reached the stable high Coulombic efficiency earlier than the pristine material. High resolution teM images and XpS results indicate that there is a disordered surface layer formed after the plasma treatment, by which defects (oxygen vacancies) and N-doping are also introduced into the crystalline structure. All these contribute to the enhancement of the electrochemical performance. Rechargeable sodium ion batteries (SIBs) have been considered as the competitive alternative to lithium ion batteries because of some special merits, such as environment friendly, low cost and especially abundant alkali element widely distributed on earth 1-3. However, there is a big challenge that the ion radius of Na ions are ~ 70% larger than that of Li ions, so finding proper electrode materials which could provide big interstitial space to accommodate sodium ions and allow reversible and rapid ion insertion/extraction 3 is a challenging topic at the moment. Recently, many efforts have been made to explore advanced anode materials for sodium ion batteries. Firstly, carbonaceous material is an important choice which is very cheap however carbonaceous materials show undesired properties with low capacities and/or poor cycle performance 4. Secondly, Ti-based materials is a promising anode materials for sodium ion batteries, including Na 2 Ti 3 O 7 , Na 0.66 [Li 0.22 Ti 0.78 ]O 2 , Li 4 Ti 5 O 12 , and titanium dioxide (TiO 2) 5. Moreover, other materials based on alloying reactions (such as Sn, Sb, P and their compounds e.g. inter-metallics, oxides, sulfides, and phosphides) 6-10 and conversion reactions (oxides and sulfides, e.g. Fe 2 O 3 ,

Visible Light Driven Photocatalytic Decolorization and Disinfection of Water Employing Reduced TiO2 Nanopowders

“…Furthermore, as shown at Figure 3d, the C-TiO2 nanoparticles were terminated by highly crystalline sharp facets, while arrows at Figure 3 e and f indicate the formation of a distorted surface layer of ~1 nm thickness in the case of H-TiO2 and N-TiO2. This phenomenon is well known and discussed for black TiO2 and was also reported by Wang et al, where surface distortion in TiO2 nanoparticles was also observed after hydrogen and nitrogen plasma treatments [17,33]. The absorption properties of the TiO2 powders derived from the diffuse reflectance measurements at room temperature are summarized in Figure 4.…”

Improving Silicon Photocathode Performance for Water Reduction through Dual Interface Engineering and Integrating ReS2 Photocatalyst

“…As shown in Figure b, the b-Si peak located at 69.3° is the (400) facet of crystalline Si . The peaks at 2θ = 25 and 37.5° are (101) and (004) planes of the anatase phase TiO 2 . It means that the ALD-deposited TiO 2 was transferred from the amorphous phase (see Figure S5) to the anatase phase during further fabrication procedure.…”

“…40 The peaks at 2θ = 25 and 37.5°are (101) and (004) planes of the anatase phase TiO 2 . 42 It means that the ALDdeposited TiO 2 was transferred from the amorphous phase (see Figure S5) to the anatase phase during further fabrication procedure. The remaining peaks in the diffractograms belong to the ReS 2 nanosheets.…”

Titania/graphene nanocomposites from scalable gas-phase synthesis for high-capacity and high-stability sodium-ion battery anodes

“…Among them, anatase has a higher theoretical storage capacity of 335 mAh g −1 and a lower energy barrier for the insertion of Na + than rutile and amorphous TiO 2 [22]. Nano-sized particles offer a high surface-to-volume ratio to facilitate ion transport, overcoming the long diffusion time of large Na + ions into the TiO 2 crystal structure [24,25]. In addition, small particle sizes reduce the effect of mechanical strain during the intercalation/deintercalation of Na + because they enable the dissipation of mechanical stress via the surface.…”