In scientific writing, it is customary to capitalize the first letter of the names of specific elements and particles, such as "Neutron", "Proton", and "Electron". This is done to distinguish them from general terms and concepts. For example, we would write "the nucleus of an atom contains protons and neutrons", but "the electrons in an atom are arranged in shells".

While it is not strictly necessary to capitalize these terms, doing so helps to maintain clarity and consistency in scientific writing. It also allows for quick and easy identification of specific elements and particles in a text.

Therefore, it is generally recommended to capitalize the first letter of the names of elements and particles in scientific writing, including terms such as "Neutron", "Proton", and "Electron".