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The treatment of dyes in wastewater is important to solve environmental problems. Advanced oxidation processes has been proved to be an effective treatment. In this work, a novel nanocomposite catalyst of ZIF-9@Fe3O4 (cobalt-containing zeolitic imidazolate framework-9 coated Fe3O4 nanocomposite) modified reduced graphite oxide (RGO) was prepared for the first time and coded as ZIF-9@CA-Fe3O4/RGO. Then, ZIF-9@CA-Fe3O4/RGO was immobilized on a cellulose membrane to obtain a composite membrane, which was used as a composite catalyst for activating peroxymonosulfate to degrade methylene blue (MB). The results demonstrated that the composite membrane could efficiently degrade approximately 96% of MB in 9 min without adjusting the initial pH and maintain good catalytic activity even after seven cycles. Furthermore, the composite membrane can be easily separated from the solution at the end of the reaction. This work indicates that the composite membrane has a broad application prospect in industrial applications. [ABSTRACT FROM AUTHOR]

The heterogenized metallomacrocycles with atomically dispersed active sites are identified as the promising candidates for electrocatalytic CO 2 reduction reaction (CO 2 RR), where their unique heterointerface with interaction between sp2 carbon and macrocyclic molecules is important but remains vague. Herein, based on well-structured nickel phthalocyanine and porphyrin with the same functional groups (MeNiPc and MeNiPp), the influences of heterointerfacial effect on catalytic performances are systematically disclosed. Through the molecular structure-induced self-adaptive adsorption with optimized heterointerfacial distance, MeNiPc/graphene reveals a high CO Faradaic efficiency of ~99% in a wide potential window, greatly outperforming the MeNiPp/graphene counterpart (≤29.6%). Detailed measurements and theoretical calculations decipher that the higher CO 2 RR activity of MeNiPc/graphene is attributed to the unique electronic structures of the Ni-N 4 configurations suitable for well-suited heterointerfacial charge transfer and rapid CO desorption. Additionally, the extended research confirms the universality of heterointerface engineering on boosting the catalytic performances. [Display omitted] • The influences of heterointerfacial effect in CO 2 RR were systematically disclosed. • Well-suited heterointerfacial charge transfer steers 99.4% CO Faradaic efficiency. • Confirming the universality of heterointerface engineering on boosting activity. [ABSTRACT FROM AUTHOR]

Designed alloy catalysts have shown promise in structure-controlled growth of single-wall carbon nanotubes (SWCNTs). However, due to the high-dimensional growth parameter space and low efficiency of the conventional trial-and-error optimizing approach, it is still challenging to explore and to establish the relations between catalyst compositions and the structure of SWCNTs. Here, we present a high-throughput strategy to investigate the statistical patterns in catalyst activity and selective growth of SWCNTs using Co/Pt/Mo ternary catalysts. Statistical analysis reveals that in the Co/Pt/Mo ternary diagram, there is an active region in the Co-rich Co–Mo corner to grow SWCNTs with high yield (≥25 tubes/μm2) and high quality (I G / I D ≥ 40). Enriched semiconducting (s-) SWCNTs with a purity higher than 90% were obtained along the boundary of the high yield region, near the Co–Pt axis. The statistical patterns of the yield, quality and selectivity are associated with the alloy composition, revealing a negative correlation between the yield and enrichment of s-SWCNTs. High-resolution transmission electron microscope characterization shows that a Co–Pt alloy catalyst with a uniform size distribution facilitates the s-SWCNT enrichment. And the separate phases of a Co–Mo/Co catalyst stabilize the active Co phase, leading to long catalyst lifetime and high yield of SWCNTs. A high-throughput strategy is developed to investigate the statistical patterns of the catalyst activity and the selective growth of single-wall carbon nanotubes (SWCNTs) grown from Co/Pt/Mo ternary catalysts. The structure of Co/Pt and Co/Mo catalysts linked with SWCNTs are further identified by using high-resolution transmission electron microscope. [Display omitted] [ABSTRACT FROM AUTHOR]

High-purity (∼96%) isolated s-SWCNT film with narrow diameter distribution were prepared on large scale by oxygen-assisted FCCVD method. [Display omitted] • Bulk isolated s-SWCNT films with a high content of 96% were selectively prepared. • O 2 was found to play function on catalyst particle size and s-SWCNT diameter. • FET devices show good performance verifying the enrichment of s-SWCNTs. Semiconducting single-wall carbon nanotubes (s-SWCNTs) are promising for use in flexible electronics as a channel material. However, it remains a big challenge to directly grow high purity, high-quality s-SWCNTs in large scale. Here we report the synthesis of isolated s-SWCNTs by an oxygen-assisted floating catalyst chemical vapor deposition method. By controlling the density of nucleated SWCNTs, isolated or small-bundled, rather than large-bundled SWCNTs were generated in a floating state, so that the oxygen introduced could more efficiently selectively etch the metallic-SWCNTs formed. In addition, it was found that the oxygen also functions in limiting the size of Fe catalyst nanoparticles in a narrow range of 5–8 nm. As a result, isolated s-SWCNTs with a narrow diameter distribution were synthesized. The content of s-SWCNTs reached ∼96%, and the percentage of isolated tubes was estimated to be ∼83%. Thin-film transistors (TFTs) constructed using the s-SWCNT film showed high on/off ratios ranging from 2.1 × 104 to 1.2 × 106, verifying the effective enrichment of s-SWCNTs. [ABSTRACT FROM AUTHOR]