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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]

We report an efficient approach to assemble a variety of electrostatically stabilized all-inorganic semiconductor nanocrystals (NCs) by their linking with appropriate ions into multibranched gel networks. These all-inorganic non-ordered 3D assemblies benefit from strong interparticle coupling, which facilitates charge transport between the NCs with diverse morphologies, compositions, sizes, and functional capping ligands. Moreover, the resulting dry gels (aerogels) are highly porous monolithic structures, which preserve the quantum confinement of their building blocks. The inorganic semiconductor aerogel made of 4.5 nm CdSe colloidal NCs capped with I− ions and bridged with Cd2+ ions had a large surface area of 146 m2 g−1. [ABSTRACT FROM AUTHOR]

One plausible approach to endow aerogels with specific properties while preserving their other attributes is to fine-tune the building blocks. However, the preparation of metallic aerogels with designated properties, for example catalytically beneficial morphologies and transition-metal doping, still remains a challenge. Here, we report on the first aerogel electrocatalyst composed entirely of alloyed PdNi hollow nanospheres (HNSs) with controllable chemical composition and shell thickness. The combination of transition-metal doping, hollow building blocks, and the three-dimensional network structure make the PdNi HNS aerogels promising electrocatalysts for ethanol oxidation. The mass activity of the Pd83Ni17 HNS aerogel is 5.6-fold higher than that of the commercial Pd/C catalyst. This work expands the exploitation of the electrocatalysis properties of aerogels through the morphology and composition control of its building blocks. [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]

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]

Facet Stabilization, Five-Fold Twinned Au Star, Particle Attachment, Sequence-Defined Peptoids 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 Nanoparticles b The peptoid-directed formation of five-fold twinned Au nanostars through particle attachment and facet stabilization is reported by James J. DeYoreo, Chun-Long Chen et al. in their Research Article (e202201980). Frontispiece: Peptoid-Directed Formation of Five-Fold Twinned Au Nanostars through Particle Attachment and Facet Stabilization. [Extracted from the article]