Mn‐Doped Perovskite Nanocrystals for Photocatalytic CO₂ Reduction: Insight into the Role of the Charge Carriers with Prolonged Lifetime

Abstract

As an emerged photocatalyst, perovskites have attracted enormous interest in photocatalysis due to their excellent photoelectronic properties. However, most of the photoexcited electron–hole pairs recombine together before they reach the surface of perovskite for photocatalysis. The undesired charge recombination would compete with the surface photocatalytic reaction. Hence, the regulation of charge carriers is essential for improving the photocatalytic performance of perovskites. Herein, the charge transfer dynamics by doping Mn2+ in CsPbCl3 perovskite nanocrystals (NCs) is manipulated and the role of the charge carriers with a prolonged lifetime in photocatalysis is investigated. The photogenerated charge carriers with a prolonged lifetime at both Mn2+ dopants and conduction band (CB) endow Mn:CsPbCl3 NCs with an enhanced photocatalytic activity toward CO2 reduction. The doping strategy provides us with a powerful tool to regulate the charge transfer dynamics in perovskite NCs for photocatalysis. It is believed that the long‐lived charge carriers in perovskite NCs have great potential in promoting charge separation and suppressing charge recombination in solar‐to‐fuel conversions.

Surface Halogen Compensation on CsPbBr3 Nanocrystals with SOBr2 for Photocatalytic CO2 Reduction

“…12−19 However, the photocatalytic performance of most MHP NCs is largely limited by severe charge recombination. 20 To overcome this problem, various semiconductor or metal cocatalysts were coupled with MHP NCs to form heterojunctions for suppressing undesired charge recombination. 21−38 The charge transfer efficiency in heterojunctions is highly dependent on the interfacial interactions between MHP NCs and nearby cocatalysts.…”

“…With the ever-increasing concerns on fossil fuel consumption and carbon dioxide (CO 2 ) overproduction, the scientific community has been searching for a solution to decrease CO 2 emission and utilize CO 2 in a sustainable way. − Photocatalytic CO 2 reduction is a potential capstone technology to convert CO 2 into high-value-added chemicals. − However, a grand challenge still remains in achieving an efficient photocatalytic system for CO 2 reduction. Concerning the excellent photoelectrical properties, , such as strong light harvesting ability, tunable band gaps, and low exciton binding energy, metal halide perovskite nanocrystals (MHP NCs) are regarded as an ideal candidate for photocatalysis. − However, the photocatalytic performance of most MHP NCs is largely limited by severe charge recombination . To overcome this problem, various semiconductor or metal cocatalysts were coupled with MHP NCs to form heterojunctions for suppressing undesired charge recombination. − The charge transfer efficiency in heterojunctions is highly dependent on the interfacial interactions between MHP NCs and nearby cocatalysts. , However, high-quality and monodispersed MHP NCs, generally prepared by hot-injection or ligand-assisted reprecipitation methods, , are capped with long-chain organic ligands, which impede the electronic coupling between MHP NCs and cocatalysts .…”

Metal-doping of halide perovskite nanocrystals for energy and environmental photocatalysis: challenges and prospects

“…This work effectively reduces the cost of metal-doped HPNCs and promotes the practical photocatalysis application of metal-doped HPNCs. Recently, Li et al 121 tuned the charge transfer kinetics by doping Mn 2+ in CsPbCl 3 HPNCs and investigated the role of charge carriers with extended lifetimes in photocatalysis. Mn 2+ doping CsPbCl 3 extended carrier lifetime, suppressed photoexcitation-separated holes and caused charges to recombine before photocatalytic reduction of CO 2 .…”

Z‐scheme SnS2/CsPbBr3 Heterojunctions for Photoreduction CO2 Reaction and Related Photoinduced Carrier Behaviors

“…[15] Still, research on CsPbBr 3 -related photocatalysts for photocatalytic CO 2 reduction and developing an effective Z-scheme system to enhance the photocatalytic property of CsPbBr 3 is at a primary stage, and how photogenerated carriers can influence CO 2 reduction reaction is still unclear. [16] In this work, aiming at further improving photogenerated carrier separation efficiency and demonstrating the CsPbBr 3 -related heterojunction property, a new heterojunction photocatalyst for photocatalytic CO 2 reduction has been constructed by modifying SnS 2 on CsPbBr 3 nanocrystals (NCs) for the first…”

“…[ 15 ] Still, research on CsPbBr 3 ‐related photocatalysts for photocatalytic CO 2 reduction and developing an effective Z‐scheme system to enhance the photocatalytic property of CsPbBr 3 is at a primary stage, and how photogenerated carriers can influence CO 2 reduction reaction is still unclear. [ 16 ]…”