Iron–Gold Galvanic-Assisted Rapid Grafting of Polymer Brushes on n-Silicon for a Triboelectric Nanogenerator

Abstract

The surface-initiated iron(0)-mediated controlled radical polymerization (SI-Fe 0 CRP) has attracted considerable interest in interface modification because it allows the controlled growth of various polymer brushes on arbitrary substrates under ambient conditions. In order to further expand the polymer brush for different application fields, herein, we propose a robust approach, namely, galvanic-cell-assisted surface-initiated Fe(0)-mediated atom transfer radical polymerization (gc-SI-Fe 0 ATRP). In gc-SI-Fe 0 ATRP, an iron-based galvanic cell allows continuous and rapid dissociation of Fe ions in an aqueous environment due to the galvanic-effectaccelerated corrosion of Fe. Through this approach, microliter volumes of various vinyl monomers could be rapidly converted to polymer brushes (up to 864 ± 67 nm in 30 min) with excellent controllability and chain-end fidelity (e.g., the successful preparation of the triblock brushes). We also demonstrate that the gc-SI-Fe 0 ATRP could efficiently polymerize ionic poly-(methacryloyloxy)ethyl trimethylammonium chloride (PMETAC) brushes on large-area n-type silicon for a triboelectric nanogenerator (PB-TENG), which provides an excellent power output of 4.97 μW m −2 , more than 11 times higher than the TENG without polymer brush grafted. This work demonstrates an efficient strategy for synthesizing polymer brushes and their potential in the functionalized electrodes for TENGs.

Roughness-Mediated SI-Fe0CRP for Polymer Brush Engineering toward Superior Drag Reduction

“…Surface-initiated zerovalent metal-mediated controlled radical polymerization (SI-Mt 0 CRP) is becoming a valuable method to modulate the chemical and physical properties of interfaces, − which has been widely utilized in the fields of responsive actuation, lubrication, , sensor, , antifog, , energy harvesting, ,, and biomedical engineering. , Recently, the Fe(0)-based SI-CRP systems have attracted special interest due to the merits of low cost, biocompatibility, , and environmental friendliness. , However, compared to other transition metal catalysts (e.g., Cu 0 ), ,− the Fe(0)-based catalysts were limited by their low efficiency and narrow monomer range. ,, Moreover, the technical difficulties in performing surface-initiated iron(0)-mediated controlled radical polymerization (SI-Fe0CRP) with a large reaction area are due to the weak oxygen resistance, which hamper the practical application of polymer brushes based on large substrates.…”