How to list all product groups in footer

[BabaVoss]

Hi, I would like to list all of my product groups in the footer (common to all pages) and when the user clicks on a group, it will redirect to respective product group page. 

This is what I've managed to do so far:

<ul class="list-unstyled text-left">
  {foreach $productGroups as $productGroup}
     <li class="my-2">
        <a href="{$productGroup->getRoutePath()}" class="footer-item">{$productGroup->name}</a>
     </li>
  {/foreach}
</ul>

This is working fine for the homepage, but fails on other pages. No data is being shown in any other page. Is there any improved method to do this?