Co-axial electrospinning was applied for the structuring of non-woven webs of TiO 2 nanofibers loaded with Ag, Au, and CuO nanoparticles. The composite layers were tested in an electrochromic half-cell assembly. A clear correlation between the nanoparticle composition and electrochromic effect in the nanofibrous composite is observed: TiO 2 loaded with Ag reveals a black-brown color, Au shows a dark-blue color, and CuO shows a dark-green color. For electrochromic applications, the Au/TiO 2 layer is the most promising choice, with a color modulation time of 6 s, transmittance modulation of 40%, coloration efficiency of 20 cm 2 /C, areal capacitance of 300 F/cm 2 , and cyclic stability of over 1000 cycles in an 18 h period. In this study, an unexplored path for the rational design of TiO 2 -based electrochromic device is offered with unique color-switching and optical efficiency gained by the fibrous layer. It is also foreseen that co-axial electrospinning can be an alternative nanofabrication technique for smart colored windows.

Photocatalytic H2 generation by water splitting is a promising alternative for producing renewable fuels. This work synthesized a new type of Ta2O5/SrZrO3 heterostructure with Ru and Cu (RuO2/Cu x O/Ta2O5/SrZrO3) using solid-state chemistry methods to achieve a high H2 production of 5164 μmol g–1 h–1 under simulated solar light, 39 times higher than that produced using SrZrO3. The heterostructure performance is compared with other Ta2O5/SrZrO3 heterostructure compositions loaded with RuO2, Cu x O, or Pt. Cu x O is used to showcase the usage of less costly cocatalysts to produce H2. The photocatalytic activity toward H2 by the RuO2/Cu x O/Ta2O5/SrZrO3 heterostructure remains the highest, followed by RuO2/Ta2O5/SrZrO3 > Cu x O/Ta2O5/SrZrO3 > Pt/Ta2O5/SrZrO3 > Ta2O5/SrZrO3 > SrZrO3. Band gap tunability and high optical absorbance in the visible region are more prominent for the heterostructures containing cocatalysts (RuO2 or Cu x O) and are even higher for the binary catalyst (RuO2/Cu x O). The presence of the binary catalyst is observed to impact the charge carrier transport in Ta2O5/SrZrO3, improving the solar to hydrogen conversion efficiency. The results represent a valuable contribution to the design of SrZrO3-based heterostructures for photocatalytic H2 production by solar water splitting.

Access to nanofabrication strategies for crafting three-dimensional plasmonic structures is limited. In this work, a fabrication strategy to produce 3D plasmonic hollow nanopillars (HNPs) using Talbot lithography and I-line photolithography...

A study is carried out to develop a surface modified Mg based alloy with an improved discharge capacity that would be durable in alkaline environment. For this purpose, Mg50Ni50 alloy is synthesized via ball milling of elemental powders and tested electrochemically in both bare and nafion coated form. The study shows that the bare electrode yields an acceptable discharge capacity but subject to a fast capacity decay. Nafion coating is effective in reducing the capacity decay where the discharge capacity after 20 cycle is as high as 82% of the initial capacity. The study further shows that there is a substantial increase in the discharge capacity of the electrode with nafion coating. This is also investigated with a more traditional alloy of (La 0.70 Mg 0.30 ) 2 (Ni 0.85 Co 0.15 ) 7 . The capacities which are 329 and 334 mAh/g in bare electrodes, in the first cycle, are increased to 498 and 448 mAh/g with nafion coating for Mg 50 Ni 50 and La 0.70 Mg 0.30 ) 2 (Ni 0.85 Co 0.15 ) 7 respectively. It is proposed that the increase in discharge capacity is due to the increase in local hydrogen pressure at electrode-nafion interface made possible by the nafion envelope resulting in the increased hydrogen storage in the active powders.

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