Chief journalist is working to expose famous scientist (6)
I believe the answer is:
edison
'scientist' is the definition.
(I've seen this before)
'chief journalist is working to expose famous' is the wordplay.
'chief journalist' becomes 'dis' (I can't explain this - if you can you should believe this answer much more).
'is working' becomes 'on' (on can mean working or activated).
'to' is a charade indicator (letters next to each other) (I've seen this in other clues).
'expose' means to look at the middle letters (I've seen 'exposed' mean this (outside letters removed)).
'famous' becomes 'great' (I've seen this in another clue).
The middle letter of 'great' is 'e'.
'dis'+'on'='dison'
'dison' after 'e' is 'EDISON'.
Can you help me to learn more?
(Other definitions for edison that I've seen before include "Onside with great American inventor" , "US scientist/inventor" , "Science master" , "Incandescent light inventor" , "US inventor of phonograph, electric light etc." .)