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I've seen a few questions on this site confirming that the mitzvah for wearing tefillin is during the entire day. Indeed, on Tish'a B'Av tefillin is not worn in the morning for Shacharit but for Mincha.
However, while I haven't seen anyone wearing tefillin at night, if one did, would he fulfil the requirement of wearing tefillin for that day? If not, what is the source / support that tefillin can be worn only during daylight hours, and when does the permissible time end?
SA OC 30:2 rules that
One is prohibited to put Tefillin on at night since he may forget [that he has them on] and sleep in them. But if he puts them on before the sun sets and it happens to get dark, even if he wears them the whole night, it is permitted.
The Rambam (Hilchot Tefillin end of 4:11) rules this is a transgression d'oraita.
A person who puts on tefillin after sunset transgresses a Scriptural prohibition, as [implied by Exodus 13:10]: "And you shall observe this statute... from day to day."
Since we have a rule that one does not get credit for a mitzva ha-ba'a be-aveira (a mitzva that came by the way of a transgression through the same object, see e.g., here), one wouldn't fulfil the requirement of wearing tefillin for that day.
The last time for putting on tefillin ideally is before shkia, or before tzeit hakochavim but there is a debate if one can say the blessing (see OC 30:2 with commentaries, or here and here).
