Metal Ion-Linked Molecular Multilayers on Inorganic Substrates: Structure and Applications

Abstract

Metal ion-linked multilayers have emerged as a simple and modular means of assembling molecular components on an inorganic substrate. The choice of molecules, based on their excited state energies and redox potentials, has enabled the directional control of energy and electron transfer events for application in electrochromics, solar energy harvesting, molecular rectifiers, photocatalysis, and more. Here, we recount the more than 35-year journey of metal ion-linked multilayers and their transition from planar to mesoporous substrates and from homogeneous to heterogeneous multilayers. This includes showcasing the vast range of components (i.e., substrates, metal ions, and molecules), structural insights, and applications. We also highlight current limitations in our knowledge of and ability to control these systems which must be overcome to realize the full potential of metal ion-linked multilayers.

Photoredox Cascade Catalyst for Efficient Hydrogen Production with Biomass Photoreforming

“…The dye sensitization technique has been widely applied to effectively harvest sunlight by systematically controlling dye absorption [29–31] . Although most dye‐sensitized photocatalysts (DSPs) suffer from charge‐recombination at the dye–semiconductor interface, [32–33] this issue could be overcome by utilizing multiple dye and electron‐mediator layers to form a photoredox cascade structure [34–37] . Furthermore, this molecular‐assembly technique would make it possible to control the surface reactivity of the DSP with an electron mediator [35–36] .…”

“…[29][30][31] Although most dye-sensitized photocatalysts (DSPs) suffer from charge-recombination at the dye-semiconductor interface, [32][33] this issue could be overcome by utilizing multiple dye and electron-mediator layers to form a photoredox cascade structure. [34][35][36][37] Furthermore, this molecular-assembly technique would make it possible to control the surface reactivity of the DSP with an electron mediator. [35][36] In this work, to open a new avenue for biomass photoreforming, a new three-step photoredox cascade catalyst (PRCC, Scheme 1) consisting of TEMPO and a dual-dye sensitized photocatalyst (DDSP = Zr-RuCP 6 -Zr-RuP 6 @Pt-TiO 2 ) was fabricated.…”

Dual-productive photoredox cascade catalyst for solar hydrogen production and methylarene oxidation

“…20–22 Recent developments on photosensitizing dye assembly on a semiconductor surface suggest that suitable assembling of photosensitizing dyes and electron mediators to form multiple photoredox cascade structures like the electron transport chain in natural photosynthesis is beneficial in separating electron–hole pairs as well as reduction and oxidation sites. 23–31 In this work, we developed a new photoredox cascade catalytic (PRCC, Scheme 1) system by combining a dual-dye ( RuCP 6 and RuP 6 ) sensitized Pt–TiO 2 H 2 production photocatalyst (DDSP) 27 and N -hydroxyphthalimide (NHPI) 32–34 that can act as the hydrogen atom transfer (HAT) mediator to activate benzylic/allylic C–H bonds of various organic substrates.…”