▎ 摘　　要

Surface-assisted bottom-up synthesis of graphene nanoribbons, which consists of the radical polymerization of precursors followed by dehydrogenation, attracted much attention due to capable of controlling their edges and widths. Although these reactions on metal surface have been believed to be catalytic, the mechanism has remained unknown. We demonstrate a new concept of 'conformation-controlled surface catalysis'; the two-zone chemical vapor deposition of the 'Z-bar-linkage' precursor, which represents two terphenyl units are linked like a 'Z', exhibiting flexible geometry that allows it to adopt chiral conformations with height-asymmetry on a Au (111) surface, results in the efficient formation of acene-type graphene nanoribbons (GNRs) with a width of 1.45 nm through optimized cascade reactions. These cascade reactions on surface include the production of self-assembled homochiral polymers in a chain with a planar conformation, followed by efficient stepwise dehydrogenation via a conformation-controlled mechanism. Our proposed concept of bio-inspired surface catalytic reactions analogous to the biological catalyst, enzyme, is useful for the fabrication of new nanocarbon materials. Additionally, we report 'Z-bar-linkage' precursor, which was extended to quarter phenyl branch from terphenyl branch formed the unique nanostructures on surface.