The rational design and controllable synthesis of hollow nanoparticles with both a mesoporous shell and an asymmetric architecture are crucially desired yet still significant challenges. In this work, a kinetics-controlled interfacial super-assembly strategy is developed, which is capable of preparing asymmetric porous and hollow carbon (APHC) nanoparticles through the precise regulation of polymerization and assembly rates of two kinds of precursors. In this method, Janus resin and silica hybrid (RSH) nanoparticles are first fabricated through the kinetics-controlled competitive nucleation and assembly of two precursors. Specifically, silica nanoparticles are initially formed, and the resin nanoparticles are subsequently formed on one side of the silica nanoparticles, followed by the co-assembly of silica and resin on the other side of the silica nanoparticles. The APHC nanoparticles are finally obtained via high-temperature carbonization of RSH nanoparticles and elimination of silica. The erratic asymmetrical, hierarchical porous and hollow structure and excellent photothermal performance under 980 nm near-infrared (NIR) light endow the APHC nanoparticles with the ability to serve as fuel-free nanomotors with NIR-light-driven propulsion. Upon illumination by NIR light, the photothermal effect of the APHC shell causes both self-thermophoresis and jet driving forces, which propel the APHC nanomotor. Furthermore, with the assistance of phase change materials, such APHC nanoparticles can be employed as smart vehicles that can achieve on-demand release of drugs with a 980 nm NIR laser. As a proof of concept, we apply this APHC-based therapeutic system in cancer treatment, which shows improved anticancer performance due to the synergy of photothermal therapy and chemotherapy. In brief, this kinetics-controlled approach may put forward new insight into the design and synthesis of functional materials with unique structures, properties, and applications by adjusting the assembly rates of multiple precursors in a reaction system.

Alloy/perovskite composites prepared by exsolution of Fe-based perovskite have attracted wide attention due to their embedded and well-anchored structure, which have broad applications in heterogeneous catalysis and energy conversion. Herein, we use Co-doped lanthanum ferrite as a model to study the effect of doping on the B-site exsolution of Fe-based perovskite. CoFe alloy can be exsolved from La0.9Fe0.9Co0.1O3 (LFCO) after heat treatment at 500 °C in a reduced atmosphere, whereas Fe will not be exsolved from La0.9FeO3 (LFO). Density functional theory calculations revealed that the stability of LFCO decreased after Co is doped into the lanthanum ferrite perovskite lattice and the formation energy of the Co–Fe bond on the surface of LFCO is lower than that of Fe–Fe in LFO, which promises an easier exsolution of CoFe alloy than the pristine Fe cluster. In addition, owing to the strong interaction and charge transfer between the exsolved CoFe alloy and parent perovskite, as well as the longer Fe–O bond after exsolution, the exsolved composite can act as an excellent bifunctional electrocatalyst for oxygen evolution and oxygen reduction reactions. Our work not only reveals the mechanism of the alloy exsolution in Fe-based perovskites but also provides a potential route to prepare the highly efficient electrocatalysts.

The exsolution of noble metal nanoparticles (NPs) from perovskite usually requires high doping ratio of noble metal. Herein, we constructed a RuO2/LFRO composite by the exsolution of a low Ru-substituted A-site deficient perovskite, La0.9Fe0.92Ru0.08O3 (LFRO). In this process, pure Ru NPs are in situ exsolved from LFRO via a relatively low temperature heat treatment in 5% H2/Ar. Then the exsolved Ru NPs were oxidized to RuO2 for oxygen evolution reaction (OER) applications. The RuO2/LFRO composite achieved a high OER performance compared with the pristine LFRO, which is mainly originated from the generation of electrochemically active RuO2 NPs and the improvement of conductivity. In addition, the exsolution is a reversible process that the exsolved Ru NPs can disappear into the perovskite lattice at 550 °C in air. Our work thereof demonstrates an effective strategy to minimize the dosage of precious metals for catalytic applications in different fields.

Metal−air batteries have attracted great attention because of their high energy density merits, among which zinc−air batteries (ZABs) are of great interest owing to their high energy density, intrinsic safety, and low cost. However, sluggish kinetics of the electrochemical oxygen evolution reactions and oxygen reduction reactions (OER and ORR) greatly hinder the development of ZABs. [5,6] Preparing a low-cost electrocatalyst with low overpotential and high stability is thereof a key issue. Effective synthesis methods are appealing to obtain robust catalysts. [7][8][9] Previous reports show that modifying the surface or bulk of materials by constructing composites, such as heterogeneous phase constructing, vacancy constructing, and interfacial engineering, can largely improve the performance of catalysts. [10][11][12][13] With regard to structural regulation, disrupting long-range order by constructing composite structures facilitates to obtain unexpected catalytic properties due to the synergistic coupling effect. [4,14] These methods can merely improve the performance of specific catalytic reactions, however, the method universality remains being improved.Surface modification and reconstruction are interesting topics from a viewpoint of catalysis, and many challenges Constructing composite structures is an essential approach for obtaining multiple functionalities in a single entity. Available synthesis methods of the composites need to be urgently exploited; especially in situ construction. Here, a NiS/NiFe 2 O 4 composite through a local metal−S coordination at the interface is reported, which is derived from phase reconstruction in the highly defective matrix. X-ray absorption fine structure confirms that long-range order is broken via the local metal−S coordination and, by using electron energy loss spectroscopy, the introduction of NiS/NiFe 2 O 4 interfaces during the irradiation of plasma energy is identified. Density functional theory (DFT) calculations reveal that in situ phase reconfiguration is crucial for synergistically reducing energetic barriers and accelerating reaction kinetics toward catalyzing the oxygen evolution reaction (OER). As a result; it leads to an overpotential of 230 mV @10 mA cm −2 for the OER and a half-wave potential of 0.81 V for the oxygen reduction reaction (ORR); as well as an excellent zinc−air battery (ZAB) performance with a power density of 148.5 mW cm −2 . This work provides a new compositing strategy in terms of fast phase reconstruction of bifunctional catalysts.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.202110172.

The ethanol oxidation reaction (EOR), the anode reaction of direct ethanol fuel cells, suffers from the sluggish oxidation kinetics and its low selectivity toward complete oxidation to CO2. The key...

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