attractive application potentials as battery-type anodes. [2] Heteroatom doping as one of the most popular strategies has improved Li-ion diffusion kinetics of carbons. [3] However, the dopants are mainly limited to nonmetal heteroatoms, such as N, S, and P. In fact, theoretical simulations suggested that, compared with nonmetal doping, doping of single atomic metals (SAMs) in carbon can better increase adsorption energy, decrease diffusion energy barriers, and exceptionally improve storage capacity. [4] Additionally, experimental investigations show that SAMs in carbon networks are usually coordinated by nonmetal atoms such as N, O, P, and C, [5,6] so SAMs together with their coordination atoms are just like atomic-scale metal compounds such as oxide, nitride, phosphide, and carbide. These metal compounds, especially nanosized ones composited with carbon, are well-known highly active Li-ion storage materials. [7] In the SAM-doped carbon, atomic-scale metal compounds are expected to own higher activity than those nanosized ones due to atomic interface interaction between SAMs and carbon. [6,8] Therefore, doping of SAMs will be a new pathway to design amazing carbon anodes for LICs. Carbon-supported SAMs have exhibited promising application in various catalysis fields. [5,9] Nevertheless, application of SAMs in LICs has not yet been carried out. Pyrolysis using organic precursors and metal compounds as sources is one of the most popular methods to synthesize SAM-doped carbon. [5,9a] During pyrolysis, heteroatoms of organic precursors are converted to nonmetal anchoring sites to stabilize metal atoms. Metal atoms are apt to aggregate due to high surface energy. Various strategies have been employed to suppress metal aggregation such as spatial confinement, [10] Zn-evaporation, [11] constraint of uncoordinated groups, [12] and polymer encapsulation. [13] However, these efforts mainly focus on the static modulation on the organic precursors and metal sources. In fact, evolution of metal atoms and anchoring sites during pyrolysis is a dynamic process. [13c] On the one hand, migration of metal atoms becomes more active at high temperature. On the other hand, nonmetal anchoring sites are not static but dramatically decreased by pyrolysis. Limited anchoring sites are not enough to support high loading of SAMs. The mass content of SAMs is generally less than 1.5 wt%, [5d] which is still Carbon-supported single atomic metals (SAMs) have attracted great interest in energy research. However, it is still a great challenge to control the content of SAMs in carbon. In this work, a dynamic inhibition strategy is proposed to achieve content-controllable synthesis of Cu atoms loaded in carbon nanofibers (CNFs) using polyacrylonitrile (PAN) and Cu(NO 3) 2 as precursors by electrospinning. Interestingly, N-anchoring sites in PAN-derived carbon matrix are dynamically increased to inhibit the aggregation of Cu atoms. Therefore, Cu atom content can be linearly controlled by adjusting the ratio of Cu(NO 3) 2 /PAN, and a high mass conten...

One-pot three-component Mannich reaction was carried out at room temperature using mesocellular cellular foam (MCF) silica loaded H 3 PW 12 O 40 as catalyst. The H 3 PW 12 O 40 /MCF catalyst was prepared by the traditional impregnation method and confirmed by a series of characterizations such as nitrogen adsorption, X-ray diffraction (XRD), Fourier-transform infrared spectra (FT-IR), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The results showed that the H 3 PW 12 O 40 /MCF catalyst with 50 wt% loading of H 3 PW 12 O 40 exhibited the highest catalytic activity for the Mannich reaction of benzaldehyde, aniline and acetophenone with the yield of 94% in 1.8 hours under the optimal condition. In addition, the H 3 PW 12 O 40 /MCF catalyst could be easily recycled and reused four times without significant decline of activity. This work provided an improved modification of the three-component Mannich reaction in terms of efficient activity, mild reaction conditions, clean reaction profiles and a simple workup procedure.

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