Preparation and characterisation of scandia doped dispenser cathodes Online publication date: Fri, 07-Dec-2012
by Jinshu Wang; Xi Wang; Wei Liu; Yuntao Cui; Yiman Wang; Meiling Zhou
International Journal of Nanotechnology (IJNT), Vol. 10, No. 1/2, 2013
Abstract: Scandia doped dispenser cathodes were prepared by powder metallurgy method using mixed powder of scandia doped tungsten, barium-calcium aluminates obtained by sol-gel method. The scanning electron microscope observation results indicate that the cathode has submicron quasi-spherical tungsten grains structure with homogeneous distribution of Sc2O3 and barium-calcium aluminates which dispersed over and among W grains. The cathode exhibits good emission property, i.e. the current density of this cathode can reach more than 40A/cm² at 850°Cb. The cathode has low work function of 1.43 eV. Active substance of Sc, Ba and O diffuse from the inner part of cathode to the surface to form a Ba-Sc-O multilayer having certain ratios of Ba:Sc:O which contains much more Ba than normal dispenser cathode at the surface of Sc2O3-W matrix cathode during the activation period. This active-multi-layer is considered to be responsible for copious emission capability.
Existing subscribers:
Go to Inderscience Online Journals to access the Full Text of this article.
If you are not a subscriber and you just want to read the full contents of this article, buy online access here.Complimentary Subscribers, Editors or Members of the Editorial Board of the International Journal of Nanotechnology (IJNT):
Login with your Inderscience username and password:
Want to subscribe?
A subscription gives you complete access to all articles in the current issue, as well as to all articles in the previous three years (where applicable). See our Orders page to subscribe.
If you still need assistance, please email subs@inderscience.com
Our Blog 
Follow us on Twitter 
Visit us on Facebook