Since we have never seen a black hole up close and personal, we don't know for certain. However, the same caliber of physicists that predicted they should exist in the first place not believe that through a quantum tunneling process, black holes can emit particles very slowly over time if they are big black holes like the Sun, or emit particles explosively if they are microscopic black holes.

Stephen Hawking predicted black hole evaporation back in 1975. This theoretical possibility has now joined the ranks of the other bizarre features of these truly weird objects. Because the physical vacuum is not empty, the virtual particles that exist in it can become the unwitting source of particles for black hole evaporation. As the pairs form and disappear near a black hole, the tremendous tidal gravitational forces rip them apart, sending one member of the pair into the hole, and allowing the other to escape. From the outside, this looks exactly like a black hole evaporating and losing mass.

What you have to keep in mind is that there is no known way to test this idea to prove that it really happens. The only black holes we have physical access to are located more than 6000 light years away, and the rate at which they emit their own 'Hawking Radiation' is so miniscule that even if we could study one as close as our sun, we would not detect this effect!

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