Yes, of course. There were many scientists at the time the atomic bomb was being developed who refused to work on it for moral reasons. In 1939 just as World War II began, scientists were right at the point of realizing that nuclear energy could be used to create a weapon. They all abruptly stopped publishing scientific papers on the topic for fear that one side or the other would create a nuclear bomb. There are many books on this. And much is available online, for instance on wikipedia.
Go to the library and don't be shy to ask a librarian for some help finding books on the morality of science. I myself know a mathematician who quit his line of research because he realized that his work could ultimately be used for immoral purposes.
There are countless moral issues today in modern biology because of new discoveries in genetics. In Canada there is an organization called the Canadian Bioethics Society that deals with nothing but the moral issues of modern genetic research. Issues range from the ownership or patenting of life-forms such as specially bred rats, to the moral obligation of doctors to divulge information about paternity as a result of genetic testing. That is: if a person's father is not who they think he is.
There are literally thousands of moral dilemmas created by science. There are many fiction books on the subject as well, including science fiction. Back to the subject of morality and nuclear science. Over the years many groups of physicists have formed to protest nuclear bombs. Earlier this year a group of physicists wrote the president of the United States a public letter asking that a law be created so that the president would not be able to use nuclear bombs on non-nuclear countries, such as Iran.