In-Situ crosslinking of 9,9' -spirobifluorene-based compounds for use in optoelectronic and/or in photoelectrochemical devices and manufacture thereof

A compound of formula (I)

• wherein
• X is independently selected from C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl, C4-C10 aryl, C4-C20 alkylaryl, C4-C20 alkenylaryl, and C4-C20 alkynylaryl, wherein said alkyl, alkenyl, alkynyl moieties, if they comprise 3 or more carbons, may be linear, branched or cyclic, and said alkyl, alkenyl, alkynyl, aryl, alkylaryl, alkenylaryl, alkynylaryl may be unsubstituted or substituted by C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl, C1-C10 heteroalkyl, C4 to C10 aryl, C2-C10 heteroalkenyl, C2-C10 heteroalkynyl, C4 to C10 heteroaryl, or one or more heteroatoms being selected from N, S and O;
• a and b are an integer independently being 0 or 1, wherein a+b≥1;
• and
• Z is selected from C2-C10 alkenyl, C2-C10 alkynyl, C4-C20 alkenylaryl, acetylenyl group, alkenyloxy alkyl group, —SH, acrylate group, —OH, —COOH, urethane group, ethyl ester group, C4-C20 alkoxyalkenyl, azide group, epoxy compounds, methyl oxirane group, epoxy group, oxiranyl group, and oxetanyl group, wherein Z is independently selected for groups [Z]a and [Z]b.