Viewpoint: Challenges in Colloidal Photocatalysis and Some Strategies for Addressing Them

Abstract

Colloidal semiconductor nanocrystals, or "quantum dots" (QDs), have several optical and chemical properties that give them the potential to enable nonincremental increases in the efficiencies of many types of photocatalytic reactions relevant for energy conversion and organic synthesis. Colloidal photocatalysts have many desirable characteristics of both heterogeneous and homogeneous catalysts but come with their own particular set of challenges. This viewpoint outlines some of the obstacles one first encounters when driving reactions with these colloids and offers some strategies for overcoming these obstacles, including ways to extend their excited state lifetimes, prevent corrosion by photogenerated holes, and choose a surface chemistry and buffering system for maximum colloidal stability over a range of environmental conditions.

Molecular tunability of surface-functionalized metal nanocrystals for selective electrochemical CO2 reduction

“…In contrast, pristine metallic surfaces are conventionally preferred for studies in heterogeneous catalysis. Nevertheless, the promoting effects of tailor-made ligands on heterogeneous catalysts are boldly emerging in various reactions, ranging from catalytic organic transformations [1][2][3][4][5] to photocatalysis [6][7][8] and electrocatalysis, including the oxygen-reduction reaction (ORR) 9 and the hydrogen-evolution reaction (HER). [10][11][12] The electrochemical reduction of carbon dioxide (CO 2 RR) holds enormous potential to meet modern-day challenges in energy storage thanks to its ability to convert CO 2 into energydense and transportable hydrocarbons and alcohols.…”

Light‐driven catalysis with engineered enzymes and biomimetic systems

“…2) [76,77]. Nanocrystalline sensitizers like CdS QDs have tunable electronic and surface properties, both of which can be advantageous in preparing QD-biocatalyst hybrids [78,79]. P450 BSβ catalyzes the hydroxylation of fatty acids at the α and β positions using hydrogen peroxide as an oxidant [80].…”

Quantum Dots Based Photocatalytic Hydrogen Evolution

“…Conversion of solar energy into chemical fuel as hydrogen from water splitting is one of the best solutions . Apart from bulk semiconductors and molecule chromophores, quantum dots (QDs) have emerged as a rising star as photocatalysts (Figure ) . QDs are a kind of semiconductor nanocrystals whose radius are less than their exciton Bohr radius .…”

“…[1][2][3][4][5] Apart from bulk semiconductors and molecule chromophores, quantum dots (QDs) have emerged as a rising star as photocatalysts ( Figure 1). [6][7][8][9][10] QDs are a kind of semiconductor nanocrystals whose radius are less than their exciton Bohr radius. [11,12] Typically, these QDs has a diameter from 2 nm to 20 nm and the charge carriers in QDs are confined with barriers in three dimensions.…”