Colouring and renaming items with command blocks [duplicate]
Solution 1:
Item display names do not support the JSON text component. The only features that currently use the text component are /tellraw, /title, book pages, and sign text.
You will otherwise need to use the legacy formatting codes via the section symbol (§). Be aware that this method is deprecated and will be removed in the future, replaced fully with the text component.
You can use a third-party NBT editor such as NBTExplorer to insert the section symbol.
Image example, editing the Command tag of a command block to include the section symbol:
