Search

Developing low‐cost and efficient photocatalysts to convert CO2 into valuable fuels is desirable to realize a carbon‐neutral society. In this work, we report that polymer dots (Pdots) of poly[(9,9′‐dioctylfluorenyl‐2,7‐diyl)‐co‐(1,4‐benzo‐thiadiazole)] (PFBT), without adding any extra co‐catalyst, can photocatalyze reduction of CO2 into CO in aqueous solution, rendering a CO production rate of 57 μmol g−1 h−1 with a detectable selectivity of up to 100 %. After 5 cycles of CO2 re‐purging experiments, no distinct decline in CO amount and reaction rate was observed, indicating the promising photocatalytic stability of PFBT Pdots in the photocatalytic CO2 reduction reaction. A mechanistic study reveals that photoexcited PFBT Pdots are reduced by sacrificial donor first, then the reduced PFBT Pdots can bind CO2 and reduce it into CO via their intrinsic active sites. This work highlights the application of organic Pdots for CO2 reduction in aqueous solution, which therefore provides a strategy to develop highly efficient and environmentally friendly nanoparticulate photocatalysts for CO2 reduction. [ABSTRACT FROM AUTHOR]

Electrochemiluminescence (ECL) represents a widely explored technique to generate light, in which the emission intensity relies critically on the charge‐transfer reactions between electrogenerated radicals. Two types of charge‐transfer mechanisms have been postulated for ECL generation, but the manipulation and effective probing of these routes remain a fundamental challenge. Here, we demonstrate the design of quantum dot (QD) aerogels as novel ECL luminophores via a versatile water‐induced gelation strategy. The strong electronic coupling between adjacent QDs enables efficient charge transport within the aerogel network, leading to the generation of highly efficient ECL based on the selectively improved interparticle charge‐transfer route. This mechanism is further verified by designing CdSe‐CdTe mixed QD aerogels, where the two mechanistic routes are clearly decoupled for ECL generation. We anticipate our work will advance the fundamental understanding of ECL and prove useful for designing next‐generation QD‐based devices. [ABSTRACT FROM AUTHOR]

Abstract: The development of core–shell structures remains a fundamental challenge for pure metallic aerogels. Here we report the synthesis of PdxAu‐Pt core–shell aerogels composed of an ultrathin Pt shell and a composition‐tunable PdxAu alloy core. The universality of this strategy ensures the extension of core compositions to Pd transition‐metal alloys. The core–shell aerogels exhibited largely improved Pt utilization efficiencies for the oxygen reduction reaction and their activities show a volcano‐type relationship as a function of the lattice parameter of the core substrate. The maximum mass and specific activities are 5.25 A mgPt−1 and 2.53 mA cm−2, which are 18.7 and 4.1 times higher than those of Pt/C, respectively, demonstrating the superiority of the core–shell metallic aerogels. The proposed core‐based activity descriptor provides a new possible strategy for the design of future core–shell electrocatalysts. [ABSTRACT FROM AUTHOR]