ANSWER:

This is baseless and not permissible since it’s an innovation.
Just make general dua during times of acceptance, such as in salah in your sujood, in the last tashahud, before making salam, between Azaan and iqama, during the last third of the night, begging Allah until He opens the door and answers your dua. 

Salaam, is there something like durood e quddus? I m married since 5 years & not conceived yet. Someone told my husband to write durood quddus on paper and keep it in a bowl containing rain water until the ink dissolves and give the water to his wife if she is unable to conceive. Two women in his family conceived after following this method. Is it authentic?