Custom Helper can't render content of PartialView - asp.net-mvc

Question

The html.Partial doesn't working very well, in fact it shows just path ~/Views/Shared/IconMenuPSA.cshtml, instead of showing the HTML content.
Where am I doing wrong?
My simple custom Helper in App_Code folder:
Helper
#using System.Web.Mvc.Html
#helper DefaultTitle(System.Web.Mvc.HtmlHelper html, string content) {
<br />
<div class="well well-sm text-center text-primary">
html.Partial("~/Views/Shared/IconMenuPSA.cshtml")
<p style="font-size:x-large">#content</p>
</div>
}
View
#model DatiGeneraliViewModel
#{
ViewBag.Title = "DatiGenerali";
Layout = "~/Views/Shared/_LayoutMainPage.cshtml";
}
#Scripts.Render("~/bundles/jquery")
#Scripts.Render("~/bundles/jqueryui")
#Scripts.Render("~/bundles/bootstrap")
#MyHelper.DefaultTitle(Html, "Dati Generali")
PartialView
<div style="float:left">
<!-- Split button -->
<div class="btn-group">
<a href="MainPage" class="btn btn-primary" title="Torna al cruscotto">
<span class="glyphicon glyphicon-tasks"></span>
</a>
<button type="button" class="btn btn-primary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
<span class="caret"></span>
<span class="sr-only">Toggle Dropdown</span>
</button>
<ul class="dropdown-menu" aria-labelledby="dropdownMenu1">
<li>Cruscotto</li>
<li role="separator" class="divider"></li>
<li>Dati Generali</li>
<li role="separator" class="divider"></li>
<li>Riepilogo </li>
</ul>
</div>
</div>
How do I fix this?
Thanks.