How to send Emoji with Telegram Bot API?
I faced the same issue a few days ago.. The solution is to use Bytes (UTF-8) notation from this table: http://apps.timwhitlock.info/emoji/tables/unicode
examples:
ð \xF0\x9F\x98\x81 GRINNING FACE WITH SMILING EYES
ð \xF0\x9F\x98\x89 WINKING FACE
you need to specify emoji's unicode value.
check here
these are returned by a function as emoji value like u'\U000026C4' which is snowman. although it is in python, you can apply it for php.