Enhanced Catalytic Activity of Gold@Polydopamine Nanoreactors with Multi-compartment Structure Under NIR Irradiation

Abstract

HIGHLIGHTS• Gold@polydopamine particles with multi-compartment structure were synthesized by using block copolymer of PS-b-P2VP as soft template and characterized by 3D electron tomography technique.• The particles can be applied as catalytic nanoreactors for the full kinetic study of reduction reaction of 4-nitrophenol by NaBH 4 .• The nanoreactors show remarkable enhancement of the catalytic activity under NIR irradiation. ABSTRACT Photothermal conversion (PTC) nanostructures havegreat potential for applications in many fields, and therefore, they have attracted tremendous attention. However, the construction of a PTC nanoreactor with multi-compartment structure to achieve the combination of unique chemical properties and structural feature is still challenging due to the synthetic difficulties. Herein, we designed and synthesized a catalytically active, PTC gold (Au)@polydopamine (PDA) nanoreactor driven by infrared irradiation using assembled PS-b-P2VP nanosphere as soft template. The particles exhibit multi-compartment structure which is revealed by 3D electron tomography characterization technique. They feature permeable shells with tunable shell thickness. Full kinetics for the reduction reaction of 4-nitrophenol has been investigated using these particles as nanoreactors and compared with other reported systems. Notably, a remarkable acceleration of the catalytic reaction upon near-infrared irradiation is demonstrated, which reveals for the first time the importance of the synergistic effect of photothermal conversion and complex inner structure to the kinetics of the catalytic reduction. The ease of synthesis and fresh insights into catalysis will promote a new platform for novel nanoreactor studies.

Synthetic advances of internally nanostructured polymer particles: From and beyond block copolymer

“…Another significant application of internally structured polymer particles is to use their porous structure, formed after removal of one polymer component, as a soft template to incorporate functional inorganic materials, especially in catalysis and energy storage field. [91][92][93][94] For example, Lu's group demonstrated a highly efficient sulfur-host material for lithium-sulfur batteries using porous PS-b-P2VP particles as a template. Multifunctional Ti 4 O 7 particles with interconnected-mesopore structure are facilely designed to suppress the dissolution of polysulfide, leading to excellent electrochemical performances.…”

Polydopamine-based nanoreactors: synthesis and applications in bioscience and energy materials

“…Recently, a PDA-based catalytic nanoreactor with an interconnected tunnel structure was reported using porous polystyrene-block-poly(2-vinylpyridine) particles derived from a selective swelling process to serve as a soft template (Figure 1d). 34 The advantage of using block copolymer assemblies, which have highly tunable nanostructures and are easily removed by organic solvents, is that more complex structures can be obtained. This strategy enlightens us to circumvent the aforementioned synthetic challenges by using block copolymer assemblies as soft templates, which can produce PDA nanoreactors with complex nanostructures and preserve the functionality of the PDA for further use.…”

“…Very recently, the unique photothermal conversion property has been demonstrated to promote an advanced, controllable catalytic reaction for the reduction of 4-nitrophenol (Figure 6ac). 34 A catalytically active, PDA@Au nanoreactor with multicompartment structure using porous PS-b-P2VP nanospheres as a soft template was synthesized. When applied for the reduction of 4-nitrophenol by NaBH 4 , a remarkable acceleration of the reaction upon near-infrared irradiation was demonstrated.…”

Artificial Melanogenesis by Confining Melanin/Polydopamine Production inside Polymersomes

“…[6] Different nano objects, e.g., liposomes or polymeric nanospheres have been used as PDA-coated templates to form shell-like or multicompartment structures. [7][8][9][10] However, severe drawbacks including compromised colloidal stability, especially over extended periods of time [11] (>3 months) and cytotoxicity when the melanin/PDA biopolymers are exposed at the surface of the particles [12][13][14] are common to melanin/PDA-based nanosystems. [1,[15][16][17] In order to solve these drawbacks, we drew inspiration from the architecture and functionality of melanosomes, specialized vesicles in melanocytes that produce and confine native melanin within a phospholipidic membrane and when transferred to the outer skin layer, serve to protect the epidermis from UV-related damages.…”