Synthetic Melanin Hybrid Patchy Nanoparticle Photocatalysts

Abstract

Rational design and preparation of bioinspired polydopamine (PDA)-based synthetic melanin hybrid materials with well-controlled morphologies and improved properties face a grand challenge at the current situation. Herein, we report the facile fabrication of photocatalytic CdS@PDA patchy nanoparticles with tunable inorganic patchy densities via different Cd2+-loaded PDA precursors. Both of “postdoping” and “predoping” strategies can be used to fabricate CdS@PDA hybrid NPs with distinct CdS patchy densities, which could further induce distinct physical properties and catalytic behaviors. Those resulting functional nanocomposites exhibited significantly enhanced photoactivity and photostability toward the catalytic degradation of methylene blue under visible light irradiation. We believe that the excellent adsorption, redox potential, and free-radical scavenging properties of PDA substrates could provide the outstanding photoactivity and photostability for CdS photocatalytic reaction. This work could inspire more kinds of synthetic melanin-based functional hybrids for stable, efficient, and sustainable photocatalysis.

Strategic Advances in Spatiotemporal Control of Bioinspired Phenolic Chemistries in Materials Science

“…[49] Besides the intrinsic affinity to various metal ions, the mild reducing capability of PDA toward noble metal ions favors the in situ nucleation and growth of metallic nanomaterials, a process that is known otherwise as electroless metallization. We have currently developed four types of PDA-metal hybrid materials with varying compositions and properties, namely, PDA-M n+ , [247] PDA-M, [248] and PDA-M x O y [88] /PDA-M x S y [249] and PDA-MOF. [250][251] These hybrids, with strong coordination between PDA and metals, can have greater stability and functionality for applications in energy, catalysis, and others.…”

Progress in polydopamine-based melanin mimetic materials for structural color generation

“…From this viewpoint, research focusing on the structure-function relationship between natural melanin and PDA is progressing [ 49 ]. Inspired by the functionality of natural melanin, PDA-based functional materials such as free radical scavengers [ 50 ], UV absorbers [ 51 ], metal ion probes [ 52 ], catalyst [ 53 , 54 ], and antioxidants [ 55 ] have been developed.…”

Melanin Biopolymers: Tailoring Chemical Complexity for Materials Design

“…[90] Further opportunities may derive by the clever use of melanin-containing hybrid systems based on for example, nanostructures,s ilica, halloysite,a nd zeolites. [91][92][93][94][95] Notably, PDAc an be exploited as am ultifunctional melanin-type system serving as an anoscale spacer to afford controllable nanogap sizes,ar edox-active coating to promote metal shell growth, or generating reactive oxygen species for antimicrobial applications, [96] as well as ar eactive scaffold to lock molecular probes inside the nanogap. [97] Several recent reviews may provide additional information as to the present and future of melanin-based materials.…”