Log out link in php code

Whats the correct way to display log out link in this php script?
When i use it in the sidebar it just removes the whole sidebar so i think im using it in a wrong way.

<?php
if ( is_user_logged_in() ) {
    <a href="<?php echo wp_logout_url( home_url() ); ?>">Logout</a>
} else {
    echo 'Welcome, visitor!';
}
?>