Fluid Field Modulation in Mass Transfer for Efficient Photocatalysis

Abstract

Mass transfer is an essential factor determining photocatalytic performance, which can be modulated by fluid field via manipulating the kinetic characteristics of photocatalysts and photocatalytic intermediates. Past decades have witnessed the efforts and achievements made in manipulating mass transfer based on photocatalyst structure and composition design, and thus, a critical survey that scrutinizes the recent progress in this topic is urgently necessitated. This review examines the basic principles of how mass transfer behavior impacts photocatalytic activity accompanying with the discussion on theoretical simulation calculation including fluid flow speed and pattern. Meanwhile, newly emerged viable photocatalytic micro/nanomotors with self‐thermophoresis, self‐diffusiophoresis, and bubble‐propulsion mechanisms as well as magnet‐actuated photocatalytic artificial cilia for facilitating mass transfer will be covered. Furthermore, their applications in photocatalytic hydrogen evolution, carbon dioxide reduction, organic pollution degradation, bacteria disinfection and so forth are scrutinized. Finally, a brief summary and future outlook are presented, providing a viable guideline to those working in photocatalysis, mass transfer, and other related fields.

Strategies to Enhance Interfacial Spatial Charge Separation for High‐Efficiency Photocatalytic Overall Water‐Splitting: A Review

“…[ 88 ] Heterogeneous photocatalytic reactions involve four steps for the transfer of active species and targeted reactants. [ 89 ] First, active radicals such as superoxide and hydroxyl radicals are generated. Second, the targeted reactive materials (e.g., organic substances in photodecomposition reactions) adsorb onto the surface of the photocatalyst, interacting with the active radicals.…”

Electrochemically exfoliated covalent organic frameworks for improved photocatalytic hydrogen evolution

“…14 The addition of ionic groups also enabled selfexfoliation of COFs for organization into thin membranes. 15 Electrochemical exfoliation has recently been recognized as a noninvasive and environmentally friendly exfoliation method to produce large-size 2D nanomaterials (e.g., graphene), 16,17 in contrast to many invasive exfoliation methods (e.g., mechanical exfoliation). Driven by the local electric eld, electrolytic ions would intercalate gradually into the adjacent layers and hereby break their inter-plane interactions.…”

“…Driven by the local electric eld, electrolytic ions would intercalate gradually into the adjacent layers and hereby break their inter-plane interactions. 15,18 In the case of electrochemical exfoliation of COFs, Gu proved that imine-linked COFs could be delaminated in polar organic solvent (i.e., N,Ndimethylformamide) through electrochemical redox and protonation. 19 To broaden the application of the electrochemical strategy, herein, we designed two typical amine-based COFs containing either D-A or non-D-A constitutions, with applicable band gaps for photocatalytic H 2 generation, and further exfoliated them noninvasively in water via electrochemical intercalation.…”

Amoeba‐Inspired Magnetic Venom Microrobots

“…Over long evolutionary periods, nature has selected the optimal locomotion strategies for single-cell organisms to survive, such as the cilia of Paramecium, [1] the flagella of Chlamydomonas, [2,3] stimuli, including light, [13][14][15] acoustics, [16] electricity, [17][18][19] heat, [20] and magnetic fields, [21][22][23][24][25] have fascinated robotics scientists with their wide range of applications, such as environmental remediation, [26] chemical reactions, [27,28] bioassays, [29,30] and biomedicine. [31][32][33][34] Magnetic actuation strategy is a promising choice for the construction of pseudopod robots due to its advantages of easy access, biosecurity and ease of programming.…”