This question has sense, depending on what you think it's an irrational number.
Consider the following definition:
An irrational number is a real number whose decimal expansion is infinite and has no any repetitive patterns.
This is the first definition one uses to see in school, since we understand better an assertion ("whose expansion is infinite...") than a negation ("that can not be written as $a/b$..."). In this case, it makes sense to wonder:
Can I get an irrational number from a quotient of integers?
The answer to this question is no, simply because any quotient of integers will yield a real number whose decimal expansion is either finite or has a repetitive pattern (that we call a period). However, this fact must be proved, and for instance, it is not so trivial in the infinite periodic case (this uses infinite series!).