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Fe3C nanoparticles hold promise as catalysts and nanozymes, but their low activity and complex preparation have hindered their use. Herein, this study presents a synthetic alternative toward efficient, durable, and recyclable, Fe3C-nanoparticle-encapsulated nitrogen-doped hierarchically porous carbon membranes (Fe3C/N–C). By employing a simple one-step synthetic method, we utilized wood as a renewable and environmentally friendly carbon precursor, coupled with poly(ionic liquids) as a nitrogen and iron source. This innovative strategy offers sustainable, high-performance catalysts with improved stability and reusability. The Fe3C/N–C exhibits an outstanding peroxidase-like catalytic activity toward the oxidation of 3,3′,5,5′-tetramethylbenzidine in the presence of hydrogen peroxide, which stems from well-dispersed, small Fe3C nanoparticles jointly with the structurally unique micro-/macroporous N–C membrane. Owing to the remarkable catalytic activity for mimicking peroxidase, an efficient and sensitive colorimetric method for detecting ascorbic acid over a broad concentration range with a low limit of detection (~2.64 µM), as well as superior selectivity, and anti-interference capability has been developed. This study offers a widely adaptable and sustainable way to synthesize an Fe3C/N–C membrane as an easy-to-handle, convenient, and recoverable biomimetic enzyme with excellent catalytic performance, providing a convenient and sensitive colorimetric technique for potential applications in medicine, biosensing, and environmental fields. [ABSTRACT FROM AUTHOR]

Controllable integration of two or more functional components is one of the most convenient and effective ways to obtain composite advanced materials with collective properties and improved performance. In this work, in combination with organic single crystals and metal–organic frameworks (MOFs), a novel 1D well‐defined core–shell heterostructure with single copper phthalocyanine (CuPc) ribbon cores coated with a uniform isoreticular MOF‐3 (IRMOF‐3) shell is successfully constructed. Impressively, thanks to performance the integration and synergy of the CuPc cores and the IRMOF‐3 shells, the sensor devices based on such single heterostructures exhibit outstanding selectivity for NH3 detection at ≈60% relative humidity at room temperature, the current response of which to NH3 is around 34–265 times the magnitude of response to ten potential interfering gases even in the case of the 1:100 concentration ratio of NH3 (5 ppm) and the interfering gases (500 ppm). Moreover, the detection limit of such CuPc@IRMOF‐3 sensors toward NH3 is estimated to be 52 ppb (signal to noise ratio = 3) based on 11 blank determinations, and good stability and reusability can also be achieved. This work highlights that the integration of organic single crystals and MOFs into well‐defined structures offers a new opportunity for high‐performance gas sensors. [ABSTRACT FROM AUTHOR]

Core–shell Au@zeolitic-imidazolate-framework-8 (ZIF-8) nanostructures are reported as a nanocarrier with both a high drug payload and high cancer treatment efficiency in vitro. Impressively, when used as multifunctional drug delivery vehicles, such core–shell Au@ZIF-8 nanostructures not only exhibit light- and pH-controlled drug release properties, but also provide two synergetic therapeutic modes for cancer treatment, resulting in 98% cell-killing activity after 30 min light irradiation followed by 24 h incubation even though HeLa cells are treated only by Au@ZIF-8 nanostructures loaded with 10 μM doxorubicin hydrochloride. All these results demonstrate the promising applications of this type of core–shell nanostructure in biomedical fields. [ABSTRACT FROM AUTHOR]

Efficient nonprecious‐metal oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) electrocatalysts are key for the commercial viability of fuel cells, metal–air batteries, and water‐splitting systems. Thus, high‐performance ORR and OER electrocatalysts in acidic electrolytes are needed to support high‐efficiency proton exchange membrane (PEM)‐based systems. Herein, we report a new approach to design and prepare an ultrathin N‐doped holey carbon layer (HCL) on a graphene sheet that exhibits outstanding bifunctional ORR/OER activities in both alkaline and acidic media. The edge sites of HCL are utilized to achieve selective doping of highly active pyridinic‐N. The sandwiched graphene sheet provides mechanical support, stabilizes HCL structure and promotes charge transfer. The synergetic effect of the catalyst structure overcomes the drawbacks of holey graphene approaches. The resulting ORR and OER performances are equal to or better than the top‐ranked electrocatalysts. Holey suitable: Ultrathin N‐doped holey carbon@graphene was synthesized and used as high‐performance oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) electrocatalyst in both alkaline and acidic media. [ABSTRACT FROM AUTHOR]

Seeking the cost-effective and stable electrocatalysts is urgent for oxygen evolution reaction (OER). The surface reconstruction is the key to improve the OER activity of catalysts. Herein, a simple and scalable pyrolysis approach is applied to prepare a novel self-supported electrode. This electrode is consisted of cobalt molybdate (CoMo 1 O 4) nanoparticles in-situ grow on carbon fiber paper (CP), termed as CoMo 1 O 4 @CP. And Mo-doped cobalt oxyhydroxide (Mo 1 –CoOOH) is generated from structural evolution occurring on the surface of CoMo 1 O 4 @CP. The Mo 1 –CoOOH@CP exhibits highly OER activity, which is verified by a low current overpotential of 274 mV at 10 mA cm−2, small Tafel slope (66 mV dec−1) and long-term stability (100 h) in 1 M KOH solution. In-situ Raman spectroscopy and density functional theory (DFT) calculations jointly reveal that etching of MoO 4 2- enable the surface structure of CoMo 1 O 4 @CP electrode transformation to Mo 1 –CoOOH@CP, and thereby bring dramatically enhanced OER activity. This study presents an effective approach on surface self-reconstruction of catalysts, with the characteristic of favorable OER activity, simple process and low cost. Accordingly, this sort of electrocatalyst demonstrates feasible applications in the fields of energy storage and conversion. • CoMo 1 O 4 @CP was synthesized via a facile pyrolysis approach. • The etching of MoO 4 2- cause the in-situ formed oxohydroxide. • The Mo 1 –CoOOH@CP shows low overpotential and long-term stability for OER. • This study presents an effective approach on surface reconstruction of catalysts. [ABSTRACT FROM AUTHOR]