Hey Jodie,
Unless you work in a really laid back private, hip, and cool ad agency, I would say no. T-shirts are just too casual for work and they can make you look frumpy and careless.
There are tons of more formal, appropriate options that are also cute if you are looking for that, some really soft and feminine tops with ruffles, bows, and so on.
The golden rule if you're confused is to check how your boss dresses at the office and act accordingly. Unless he's a man, in which case, look for stylish women.
And if she wears t-shirts, then see above.
Hope this helps.
