Field emission properties of RuO2 thin film coated on carbon nanotubes

Characterization of RuO2 nanocrystals deposited on carbon nanotubes by reactive sputtering

“…2 (see insets) indicate that the surface morphologies of the as-deposited RuO 2 NCs vary from nanoparticle-like to rod-like and tube-like NCs with increasing NC sizes as the oxygen flux increases from 2 to 10 sccm. The nanoparticle-like RuO 2 NCs can be used as a protective layer on CNTs, providing stable and uniform field emission [11]. While the nanotube-like structure can increase the surface-to-volume ratio which makes the RuO 2 /CNT nanocomposites as attractive candidate for the supercapacitor applications.…”

A flexible angle sensor made from MWNT/CuO/Cu2O nanocomposite films deposited by an electrophoretic co-deposition process

“…Recently, the use of carbon nanotubes (CNTs) and metal oxide nanostructures in electronic devices has attracted interest for a variety of applications; for example, CO gas sensors [1], dye sensitized solar cells [2], detectors for traces of oxygen [3], supercapacitors [4], hydrogen gas sensors [5], glucose sensors [6], field emission [7] and superior reversible Li-ion storage [8]. Many types of metal oxide have been used in CNT/metal-oxide composites, such as tin oxide (SnO 2 ) [1], titanium dioxide (TiO 2 ) [2,3], manganese oxide (MnO 2 ) [4], tungsten trioxide (WO 3 ) [5], copper oxide [6,8], ruthenium dioxide (RuO 2 ) [7] and zinc oxide (ZnO) [9].…”

“…Many types of metal oxide have been used in CNT/metal-oxide composites, such as tin oxide (SnO 2 ) [1], titanium dioxide (TiO 2 ) [2,3], manganese oxide (MnO 2 ) [4], tungsten trioxide (WO 3 ) [5], copper oxide [6,8], ruthenium dioxide (RuO 2 ) [7] and zinc oxide (ZnO) [9]. Many methods have been used to fabricate CNT/metal-oxide composites on substrates; for example, electrospinning [1], filtration [2], drop-coating [3], roll-pressing [4], spin-coating [5], inkjet printing [10], spray deposition [11], aerosol methods [12], electrophoretic deposition (EPD) [13,14], hot-pressing transfer [14] and filtration-wet transfer processes [15].…”

Outstanding field emission properties of wet-processed titanium dioxide coated carbon nanotube based field emission devices

“…[15][16][17] On the other hand, composite CNT cathodes by doping or attaching CNTs with metal nanoparticles or metal oxide thin films have been demonstrated to greatly improve the FE performance. [18][19][20][21][22][23][24][25][26][27][28] However, metal nanoparticles doped CNTs generally possess weak electron emission stability due to the chemical activity and poor oxygen resistance of metal nanoparticles. For example, Sridhar et al reported an ultralow turn on field (E to , defined as the required electric field corresponding to emission current density of 10 lA cm À2 ) and threshold field (E th , defined as the required electric field corresponding to emission current density of 1 mA cm À2 ) of 0.13 and 0.14 V lm À1 by decorating vertically aligned CNTs with Al nanoparticles, 20 yet, the stability of the decorated CNT composite still needed improvement as it already decreased over 10% in 1 h under a low bias stress of 0.15 V lm À1 .…”

“…For example, Sridhar et al reported an ultralow turn on field (E to , defined as the required electric field corresponding to emission current density of 10 lA cm À2 ) and threshold field (E th , defined as the required electric field corresponding to emission current density of 1 mA cm À2 ) of 0.13 and 0.14 V lm À1 by decorating vertically aligned CNTs with Al nanoparticles, 20 yet, the stability of the decorated CNT composite still needed improvement as it already decreased over 10% in 1 h under a low bias stress of 0.15 V lm À1 . Simultaneously, metal oxides including ZnO, 21,22 MgO, 23,24 SiO 2 , 23 anatase TiO 2 , 25 RuO 2 , 26 and barium strontium oxide 27 coated on the surface of CNTs to improve the FE performance have also been reported. It was claimed that the improved FE performance was attributed to the lowered work function of CNT/metal oxide composite films.…”