Ni3Se2 has been identified as a high-efficiency oxygen evolution catalyst with low onset potential and extended stability under alkaline conditions.

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Ni3Te2 has been reported as a highly efficient OER electrocatalyst with an overpotential of 180 mV at 10 mA cm−2 and also showing HER catalytic activity in alkaline medium.

Trisulfide molybdenum complexes have been employed to produce nanotubes by simple heating in a stream of hydrogen. Bamboo‐like stacking (see Figure) was observed, suggesting that the stimulus for the growth of MoS2 nanotubes is similar to that of their carbon equivalents. The wide experience gained with trisulfide complexes directs this technique towards the preparation of other layered sulfide nanotubes, although other precursors are also shown to be successful.

Nanorods of several oxides, with diameters in the range of 10±200 nm and lengths upto a few microns, have been prepared by templating against carbon nanotubes. The oxides include V 2 O 5 , WO 3 , MoO 3 and Sb 2 O 5 as well as metallic MoO 2 , RuO 2 and IrO 2 . The nanorods tend to be single-crystalline structures. Nanotube structures have also been obtained in MoO 3 and RuO 2 .

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Electrodeposited Co7Se8 nanostructures exhibiting flake-like morphology show bifunctional catalytic activity for oxygen evolution and hydrogen evolution reaction (OER and HER, respectively) in alkaline medium with long-term durability (>12 h) and high Faradaic efficiency (99.62%). In addition to low Tafel slope (32.6 mV per decade), the Co7Se8 OER electrocatalyst also exhibited very low overpotential to achieve 10 mA cm(-2) (0.26 V) which is lower than other transition metal chalcogenide based OER electrocatalysts reported in the literature and significantly lower than the state-of-the-art precious metal oxides. A low Tafel slope (59.1 mV per decade) was also obtained for the HER catalytic activity in alkaline electrolyte. The OER catalytic activity could be further improved by creating arrays of 3-dimensional rod-like and tubular structures of Co7Se8 through confined electrodeposition on lithographically patterned nanoelectrodes. Such arrays of patterned nanostructures produced exceptionally high mass activity and gravimetric current density (∼68 000 A g(-1)) compared to the planar thin films (∼220 A g(-1)). Such high mass activity of the catalysts underlines reduction in usage of the active material without compromising efficiency and their practical applicability. The catalyst layer could be electrodeposited on different substrates, and an effect of the substrate surface on the catalytic activity was also investigated. The Co7Se8 bifunctional catalyst enabled water electrolysis in alkaline solution at a cell voltage of 1.6 V. The electrodeposition works with exceptional reproducibility on any conducting substrate and shows unprecedented catalytic performance especially with the patterned growth of catalyst rods and tubes.

Nanowires of Au, Ag, Pt, and Pd (1.0-1.4 nm diam) have been produced in the capillaries of single-walled carbon nanotubes (SWNTs). The nanowire is single-crystalline in some cases. Dispersions of the nanowires in alcohol show longitudinal plasmon absorption bands at different wavelengths, suggesting the presence of a distribution of aspect ratios. A novel phenomenon involving the intercalation of metal layers (∼0.5 nm thick) in the intertubular space of SWNT bundles has been observed. SWNTs decorated by metal nanoparticles are formed in some of the preparations.