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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]

A photocatalyst comprising binary organic polymer dots (Pdots) was prepared. The Pdots were constructed from poly(9,9‐dioctylfluorene‐alt‐benzothiadiazole), as an electron donor, and 1‐[3‐(methoxycarbonyl)propyl]‐1‐phenyl‐[6.6]C61, as an electron acceptor. The photocatalyst produces H2O2 in alkaline conditions (1 M KOH) with a production rate of up to 188 mmol h−1 g−1. The external quantum efficiencies were 30 % (5 min) and 14 % (75 min) at 450 nm. Furthermore, photo‐oxidation of methanol by Pdots, followed by a disproportionation reaction and an oxidation reaction, produced the high‐value chemical formate. On the basis of various spectroscopic and electrochemical measurements, the photophysical processes of the system were studied in detail and a reaction mechanism was proposed. [ABSTRACT FROM AUTHOR]

Carbon‐based gas molecules are readily available feedstocks and are widely used in industry as building blocks or fuels. However, their application in the synthesis of fine chemicals has been hampered due to operational complexity, poor reaction efficiency and selectivity. Recent development of photoredox‐promoted transformations using such gaseous reagents has received considerable attention from the synthetic community. In this review, efforts in developing light‐promoted organic transformations using carbon‐based natural gases as C1 or C2 feedstocks and to overcome the associated challenges are briefly summarized. [ABSTRACT FROM AUTHOR]

The electrocatalytic oxidation of glucose plays a vital role in biomass conversion, renewable energy, and biosensors, but significant challenges remain to achieve high selectivity and high activity simultaneously. In this study, we present a novel approach for achieving complete glucose electrooxidation utilizing Cu‐based metal‐hydroxide‐organic framework (Cu‐MHOF) featuring coordinatively unsaturated Cu active sites. In contrast to traditional Cu(OH)2 catalysts, the Cu‐MHOF exhibits a remarkable 40‐fold increase in electrocatalytic activity for glucose oxidation, enabling exclusive oxidation of glucose into formate and carbonate as the final products. The critical role of open metal sites in enhancing the adsorption affinity of glucose and key intermediates was confirmed by control experiments and density functional theory simulations. Subsequently, a miniaturized nonenzymatic glucose sensor was developed showing superior performance with a high sensitivity of 214.7 μA mM−1 cm−2, a wide detection range from 0.1 μM to 22 mM, and a low detection limit of 0.086 μM. Our work provides a novel molecule‐level strategy for designing catalytically active sites and could inspire the development of novel metal–organic framework for next‐generation electrochemical devices. [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]

While bio‐inspired synthesis offers great potential for controlling nucleation and growth of inorganic particles, precisely tuning biomolecule–particle interactions is a long‐standing challenge. Herein, we used variations in peptoid sequence to manipulate peptoid–Au interactions, leading to the synthesis of concave five‐fold twinned, five‐pointed Au nanostars via a process of repeated particle attachment and facet stabilization. Ex situ and liquid‐phase TEM observations show that a balance between particle attachment biased to occur near the star points, preferential growth along the [100] direction, and stabilization of (111) facets is critical to forming star‐shaped particles. Molecular simulations predict that interaction strengths between peptoids and distinct Au facets differ significantly and thus can alter attachment kinetics and surface energies to form the stars. This work provides new insights into how sequence‐defined ligands affect particle growth to regulate crystal morphology. [ABSTRACT FROM AUTHOR]

Facet Stabilization, Five-Fold Twinned Au Star, Particle Attachment, Sequence-Defined Peptoids Frontispiz: Peptoid-Directed Formation of Five-Fold Twinned Au Nanostars through Particle Attachment and Facet Stabilization Keywords: Facet Stabilization; Five-Fold Twinned Au Star; Particle Attachment; Sequence-Defined Peptoids EN Facet Stabilization Five-Fold Twinned Au Star Particle Attachment Sequence-Defined Peptoids 1 1 1 03/23/22 20220328 NES 220328 B Nanopartikel b Die peptoiddirigierte Bildung von verzwillingten Au-Nanosternen durch Partikelanlagerung und Facettenstabilisierung wird im Forschungsartikel von James J. DeYoreo, Chun-Long Chen et al. vorgestellt (e202201980). [Extracted from the article]