PHPWord emoji and Word2007 export

I would like to know, how can I create a Word2007 document with PHPWord and see the emoji.

Currently, I create my document :

$objWriter = \PhpOffice\PhpWord\IOFactory::createWriter($phpWord, 'Word2007');
$objWriter->save($path);

But I don't see the emoji..

If I create with :

objWriter = \PhpOffice\PhpWord\IOFactory::createWriter($phpWord, 'HTML');
$objWriter->save($path);

I can see the emoji.

via Chebli Mohamed