High-performance all-solid-state yarn supercapacitors based on porous graphene ribbons

Electrospray-deposition of graphene electrodes: a simple technique to build high-performance supercapacitors

“…[1][2][3][4] Yet currently, there are still a few issues to be addressed before they find broader applications; one of the biggest issues is its tendency to irreversibly aggregate due to the strong van der Waals attraction, especially when graphene experiences compressions during the electrode fabrication process, [5][6][7] which results in the loss of accessible surface area. [1][2][3][4] Yet currently, there are still a few issues to be addressed before they find broader applications; one of the biggest issues is its tendency to irreversibly aggregate due to the strong van der Waals attraction, especially when graphene experiences compressions during the electrode fabrication process, [5][6][7] which results in the loss of accessible surface area.…”

Research Update: Strategies for efficient photoelectrochemical water splitting using metal oxide photoanodes

“…Recently, N-doped TiO 2 nanowire array photoanodes prepared by nitridation of pure TiO 2 nanowire arrays in NH 3 flow at 500 • C (i.e., post-treatments) were reported. 79 The low-energy threshold of the IPCE spectra of the N-doped TiO 2 samples was at ca. 520 nm corresponding to 2.4 eV.…”

“…However, in general, dopants incorporated by the post-treatments are distributed mainly within the subsurface region of a very limited depth (Figure 3(b)). 73,82 Limitations are caused by this non-uniform dopant distribution, such as limited visible-light absorbance 79,80 and lowered mobility of carriers in the localized states, which deteriorate visible-light photocatalytic activities. 71,82 To overcome the limitations, Liu et al used layered materials with interlayer galleries, layered titanates, as host materials for N doping by nitridation, giving products that possess a bandto-band visible light absorption edge in the blue light region via the homogeneous substitution of O by N although the products were not applied to photoanode materials (Figures 3(c) and 3(d)).…”

Doping of TiO2as a tool to optimize the water splitting efficiencies of titania–hematite photoanodes

“…Due to more negative conduction band (CB) potential of TiO 2 compared to hematite a higher recombination rate would be expected due to the band offset. 6,31 However, by applying electrochemical impedance spectroscopy, PEC and electron paramagnetic resonance studies, Luan et al evidently confirmed the occurrence of an uncommon transfer of visible-excited high-energy electrons from hematite to rutile TiO 2 . 32 It was suggested that in this process, the excited electrons in hematite populate different energy levels and while low energy electrons recombine with VB holes, high-energy electrons transfer to the CB of rutile.…”