download from here https://www.zotero.org/download/ Extract it to some folder /opt/zotero/ such that you will have zotero binary here: /opt/zotero/Zotero_linux-x86_64
Make a symbolic link so that you can run zotero from anywhere in terminal: sudo ln -s /opt/zotero/Zotero_linux-x86_64/zotero /usr/local/bin/zotero
Next step is to create a launcher icon that is searchable in ubuntu Launcher Dashboard.
upgautam@amd:~/Desktop$ nano ~/.local/share/applications/zotero.desktop
[Desktop Entry]
Version=1.0
Name=zotero
Comment=zotero library organizer
Icon=/home/upgautam/.local/share/icons/zotero.png
Exec=zotero
Icon=zotero
Terminal=false
Type=Application
Categories=Education;Offline;
As you can see above, we must have zotero. png icon in /home/upgautam/.local/share/icons/zotero.png. If you don't have then download icon from google search.
Done!
Now, search zotero and then do Pin to Dashboard.