a sans-serif letterform is one that does not have extending features called "serifs" at the end of strokes. ... often used to convey simplicity and modernity or minimalism.
It contains glyphs for every printable code point in the Unicode Basic Multilingual Plane (BMP) with growing coverage of the Supplementary Multilingual Plane (SMP).
For Emoji, getting the Supplementary version is enough. The Supplementary glyphs are also included in the full GNU Unifont fontpack.