Designable Photo-Responsive Micron-Scale Ultrathin Peptoid Nanobelts for Enhanced Performance on Hydrogen Evolution Reaction.

The development of high-reactive single atom catalysts (SACs) based on long-range-ordered ultrathin organic nanomaterials (i.e., below 3 nm) provides a significant tactic for the advancement in hydrogen evolution reactions (HER), but remains challenging. Herein, photo-responsive ultrathin peptoid nanobelts (UTPNBs) with a thickness of ∼2.2 nm and micron-scaled length were generated using the self-assembly of azobenzene-containing amphiphilic ternary alternating peptoids. The pendants hydrophobic conjugate stacking mechanism revealed the formation of one-dimensional ultralong UTPNBs, whose thickness was dictated by the length of side groups that are linked to peptoid backbones. The photo-responsive feature was demonstrated by a reversible morphological transformation from UTPNBs to nanospheres (21.5 nm) upon alternative irradiation with UV and visible lights. Furthermore, the electrocatalyst performance of these aggregates co-decorated with nitrogen-rich ligand of terpyridine (TE) and uniformly-distributed atomic platinum (Pt) was evaluated toward HER, with a photo-controllable electrocatalyst activity that highly depended on both the presence of Pt element and structural characteristic of substrates. The Pt-based SACs using TE-modified UTPNBs as support exhibited a favorable electrocatalytic capacity with an overpotential of ∼28 mV at a current density of 10 mA cm -2 . Our work presented a promising strategy to fabricate stimuli-responsive ultrathin organic nanomaterials-based catalysts with controllable HER catalytic performance. This article is protected by copyright. All rights reserved.