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1.
Inorg Chem ; 63(37): 17116-17126, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39231020

RESUMO

Precisely tuning how and where a reaction occurs in a one-step selective system is important but challenging owing to the similar electronic environments in multiple active sites. In this work, highly selective and effective reaction sites were obtained by generating copper coordination polymers (Cu-CP) of a range of sizes and morphologies, from bulk solid crystals (1) to uniform nanosphere structures (1a), by controlling the amount of surfactant hexadecyl trimethylammonium bromide (CTAB). The results indicated that the morphology and size of the uniform nanosphere structures were affected by the proportion of CTAB; uniform distribution of nanosphere structures was achieved with a premade building carrier when the content of CTAB was 0.005 mmol, generating a well-established platform. Photocatalytic cadmium sulfide (CdS) was then immobilized on the surface of the premade platform unit 1a through an in situ process to generate CdS@1a composites with well-dispersed catalytic CdS active sites. Furthermore, the well-defined CdS@1a composite platform was utilized as photocatalysts to explore the selective one-step depolymerization reaction under blue-light irradiation. Notably, the CdS0.149@1a composite, which featured a unique structure with evenly dispersed, closely spaced catalytic sites, exhibiting remarkable photoelectrochemical behaviors for selective one-step depolymerization of lignin model substances to aromatic monomer phenol and acetophenone framework products. This work demonstrates the use of an inherently morphological process to construct outstanding photocatalysts that could enable a wide range of photocatalytic reactions.

2.
J Colloid Interface Sci ; 663: 919-929, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38447406

RESUMO

Accurately controlling and achieving selective reactivity at difficult-to-access reaction sites in organic molecules is challenging owing to the similar local and electronic environments of multiple reaction sites. In this work, we regulated multiple reaction sites in a highly selective and active manner using cobalt coordination polymers (Co-CP) 1 and 1a with various particle sizes and morphologies ranging from large granular to ordered hollow hemispheres by introducing sodium dodecyl sulfate (SDS) as a surfactant. The size and morphology of the catalysts could be tuned by controlling the amount of SDS. An SDS concentration of 0.03 mmol generated 1a having a highly ordered hollow hemispherical microstructure with a well-defined platform as a pre-made building unit. Cadmium sulfide (CdS), as a typical photocatalyst, was subsequently uniformly anchored in-situ on the premade building unit 1a to produce CdS@1a composites, that inherited the originally ordered hollow hemispherical microstructure while integrating CdS as well-dispersed catalytic active sites. Furthermore, the well-established CdS@1a composites were used as photocatalysts in selective oxidation reactions under air atmosphere with blue irradiation. The CdS0.109@1a composite with unique structural characteristics, including uniformly distributed and easily accessible catalytic sites and excellent photoelectrochemical performance, served as a highly efficient heterogeneous photocatalyst for promoting the selective oxidation of sulfides to sulfoxides as the sole products. This work presents an approach for fabricating CPs as premade building units that function as well-defined platforms for integration with photocatalysts, enabling tuning of the structure-selectivity-activity relationships.

3.
Chemistry ; 29(33): e202300528, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-36905206

RESUMO

A friction layer with stability and durability is important to promote the practical application of triboelectric nanogenerators (TENGs). In this work, a two-dimensional cobalt coordination polymer (Co-CP) was successfully synthesized using cobalt nitrate, 4,4',4''-tricarboxyltriphenylamine and 2,2'-bipyridine. To clearly clarify the effect of the doping proportions of Co-CP and the types of composite polymers on the output performance of the TENG, Co-CP was combined with two organic polymers having different polarities (polyvinylidene fluoride (PVDF) and ethyl cellulose (EC)) to form a series of composite films, which were used as the friction electrode materials to fabricate TENGs. Electrical characterizations indicated that a high output current and voltage were obtained from the TENG based on 15 wt.% Co-CP incorporated in PVDF (Co-CP@PVDF), which could be further improved by the Co-CP@EC composite film at the same doping ratio. Furthermore, the optimally fabricated TENG was demonstrated to prevent electrochemical corrosion of carbon steel.


Assuntos
Polímeros , Polivinil , Carbono , Cobalto
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