The chemical components and antioxidant activity of 16 Rehmannia glutinosa samples were investigated to reveal the high‐quality raw resource for pharmaceutical products. 22 main chemical components were detected with significant content differences (P<0.05). The contents of 14 substances reached the maximum in S1 sample such as catalpol (6.74 mg g−1), rehmaionoside A (1.93 mg g−1) and rehmannioside D (5.13 mg g−1). However, the content distribution of the other eight substances had no obvious change regulation. Three antioxidant evaluation methods commonly showed that S1 sample had strong antioxidant activity with a low IC50 value of 0.022 mg mL−1, a high ABTS value of 524.196 μmol equiv. Trolox g−1, and a high FRAP value of 200.517 μmol equiv. Trolox g−1. Considered the medicinal value, S1 had high quality based on the present phytochemical profiles and antioxidant activity. These results also indicated that the root extracts of R. glutinosa could become useful supplement for pharmaceutical products as new antioxidant agents.

he discovery of tungsten carbide (WC) as an analog of noble metal Pt atom is of great significance toward designing novel highly-active catalysts from the viewpoint of the superatom concept....

Predicting superatoms with multiple desired properties is of great interest and challenge. To achieve this goal, a series of organometallic M@36adz (M = Sc ∼ Zn) complexes have been obtained by embedding the 3d transition-metal atoms into the 36adamanzane (36adz) complexant. Under the intramolecular interaction between M and 36adz, the magnetic moments of M atoms are either enhanced or preserved in the resulting M@36adz complexes. Also, the αSOMO levels of M@36adz are significantly raised by the presence of the M impurities, resulting in their greatly lower adiabatic ionization energies (AIEs) of 1.78–2.56 eV than the IE (3.89 eV) of Cs atom. As a result, these complexes can be regarded as a new kind of magnetic superalkalis. Moreover, due to the existence of diffuse electrons in their αSOMO, most of the M@36adz complexes also exhibit remarkable nonlinear optical responses with large first hyperpolarizabilities (β0) of 1.56 × 106–6.33 × 107 au. Hence, this study provides a possible strategy to design a new kind of multifunctional species with high reducing ability, magnetic properties, and large NLO responses by doping various transition metals into such cage-like organic complexants.

The unique characteristic of superatoms to show chemical properties like those of individual atoms opens a new avenue towards replacing noble metals as catalysts. Given the similar electronic structures of the ZrO superatom and the Pd atom, the CO oxidation mechanisms catalysed by (ZrO) n (n = 1-4) clusters were investigated in detail to evaluate their catalytic performance. Our results reveal that a single ZrO superatom exhibits superior catalytic ability in CO oxidation than both larger (ZrO) n (n = 2-4) clusters and a Pd atom, indicating the promising potential of ZrO as a "single-superatom catalyst". Moreover, the mechanism of CO oxidation catalysed by ZrO + /À suggests that depositing a ZrO superatom onto the electron-rich substrates is a better choice for practical catalysis application. Accordingly, a graphene nanosheet (coronene) was chosen as a representative substrate for ZrO and Pd to assess their catalytic performances in CO oxidation. Acting as an "electron sponge", this carbon substrate can both donate and accept charges in different reaction steps, enabling the supported ZrO to achieve enhanced catalytic performance in this process with a low energy barrier of 19.63 kcal/mol. This paper presents a new realization on the catalytic performance of Pd-like superatom in CO oxidation, which could increase the interests in exploring noble metal-like superatoms as efficient catalysts for various reactions.

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