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Two-dimensional (2D) hierarchical Mn2O3@graphene composite is synthesized by a one-step solid-phase reaction. The nanosheets of Mn2O3 are vertically grown on few-layered graphene, constructing a unique 2D hierarchical structure. As an anode material for lithium-ion batteries (LIBs), this hierarchical composite displays excellent electrochemical performances, showing an extraordinary reversible discharge capacity of 2125.9 mA h g–1. Moreover, a record high reversible capacity of 1746.8 mA h g–1 is maintained after 100 cycles at a current density of 100 mA g–1, which retains 82.2 % of the initial capacity. Such an outstanding performance could be attributed to its novel structure and the synergistic effects between the Mn2O3 and graphene.

Metal-based catalysts in advanced oxidation processes (AOPs) are not stable under strong acidic condition due to the remarkable leaching, which will also lead to a secondary pollution. In this study, an aminated N-doped graphene hydrogel (ANGH) is synthesized from graphene oxide and ethylenediamine (EDA) via an in-situ hydrothermal process. The ANGH shows a free-standing structure and has high catalytic activity especially in phenol degradation under strong-acidic condition because of a non-radical dominated mechanism determined in this process. On the large scale, a longer lifetime of ∼1700 min for ANGH is obtained under strong-acidic condition on a dynamic amplifying device, 2.9 times longer than that at neutral condition. It is proposed that amine N can be protected by hydrogen ions from being oxidized, thus leading to the better stability. Meanwhile, the active sites of ANGH can transform from N containing groups into oxygenous groups, and the deactivated material can be reutilized 10 times for rhodamine B degradation on a large scale. The ANGH synthesized facilely and could be recycled repeatedly, which is also very stable in the strong acidic environment, thus should have great potential in wastewater remediation.

this paper presents the design of two structures of substrate integrated waveguide (SIW) bandpass filter (BPF) for millimeter-wave application. By approaching the cruciform slot and ground vias, the numbers of resonance frequency was increased, and the filter structure can be miniaturized. Finally, the filter is designed to work at the center frequency of 22 GHz with the bandwidth of 1.4 GHz, and the numerical simulations shows good performance in the pass band and stopband.