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Different transition metal loaded metal–organic frameworks (MOFs) have been extensively studied. However, little literature has been written about alkali and alkali-earth metal-loaded MOFs. In this study, we take the DPyDFP linker used for the construction of MOFs as an example. The structures and electronic properties of alkali metals and alkaline earth metals loaded DPyDFP clusters have been investigated using density functional theory. The results indicate that the structural stability of alkali metals and alkaline earth metals loaded DPyDFP clusters is less than that of transition metals loaded DPyDFP clusters. The interior of the DPyDFP clusters has not enough space to locate a large alkali metal or alkaline earth metal atom except for Li, Be and Mg. It indicates that if the IAM and IIAM atoms are loaded on the linker to build a MOF framework, Li, Be and Mg are worth considering. The DPyDFP-IIAM clusters exhibit more structural stability and chemically stable than corresponding DPyDFP-IAM clusters. The HOMOs and LUMOs of the DPyDFP-IAM and DPyDFP-IIAM clusters mostly surround N and C atoms. The IAM-N and IIAM-N bonds exhibit certain covalent character. Due to the limited charge transfer between the IAM (or IIAM) atoms and the DPyDFP clusters, the IAM (or IIAM) atoms are not a good choice to design the novel linker to build a MOF framework. [ABSTRACT FROM AUTHOR]

The low concentration of formaldehyde (HCHO) released from decoration materials still display potential carcinogenicity due to the high toxicity of HCHO. Boron nitride nanotubes (BNNTs) as a stable material become a candidate for adsorbing HCHO. The differences in the structural stability of HCHO interacted with BNNTs with different diameters owing to the adsorption sites deserve further discussion. It provides a promising direction for the experimental preparation of appropriate diameter BNNTs. The structures, stability and electronic properties of HCHO adsorbed on the surfaces of BmNm (HCHOBmNm(s)), HCHO adsorbed at the ends of BmNm (HCHOBmNm(e)) and HCHO embedded into BmNm (HCHO@BmNm) (m = 48, 72 and 96) clusters have been investigated by using density functional theory. The results reveal that the diameter of B48N48 clusters (or (4,4) armchair single-walled BNNTs) is too small to embed HCHO while promote charge transfer between the HCHO and B48N48 clusters. The HCHOB48N48(s), HCHOB72N72(e) and HCHOB96N96(e) clusters exhibit higher chemical stability than other HCHOBmNm(s), HCHOBmNm(e) and HCHO@BmNm clusters. The results also suggest that BNNTs is an ideal material for HCHO adsorption since physisorption is helpful to recycle BNNTs. [ABSTRACT FROM AUTHOR]