Research Article Online first
Oriented magnetic liquid metal-filled interlocked bilayer films as multifunctional smart electromagnetic devices
Nano Research
Published: 13 September 2022

Smart electromagnetic functional devices prepared based on electromagnetic wave responsive materials will provide more convenience for human life in the future. Here, we prepare oriented magnetic liquid metal droplet-filled polydimethylsiloxane films with micropillar array patterned surfaces, and further assemble them into bilayer films with interlocked structures. Once compressed, the increase in conductivity of the film due to the tunneling effect between microarrays and the elongation of liquid metal droplets leads to a rapid increase in electromagnetic interference shielding performance. Accordingly, a tunable electromagnetic interference shielding material with high sensitivity and wide control range is obtained, which has potential applications in electromagnetic wave control systems and intelligent electromagnetic protection systems. Meanwhile, we assemble a strain sensor and a magnetic sensor, which can precisely sense pressure and magnetic field according to changes in electromagnetic signal and electrical signal, respectively.

Research Article Issue
Synergy between metallic components of MoNi alloy for catalyzing highly efficient hydrogen storage of MgH2
Nano Research 2020, 13 (8): 2063-2071
Published: 05 August 2020

Catalysts play a critical role in improving the hydrogen storage kinetics in Mg/MgH2 system. Exploring highly efficient catalysts and catalyst design principles are hot topics but challenging. The catalytic activity of metallic elements on dehydrogenation kinetics generally follows a sequence of Ti > Nb > Ni > V > Co > Mo. Herein, we report a highly efficient alloy catalyst composed of low-active elements of Mo and Ni (i.e. MoNi alloy) for MgH2 particles. MoNi alloy nanoparticles show excellent catalytic effect, even outperforming most advanced Ti-based catalysts. The synergy between Mo and Ni elements can promote the break of Mg-H bonds and the dissociation of hydrogen molecules, thus significantly improves the kinetics of Mg/MgH2 system. The MoNi-catalyzed Mg/MgH2 system can absorb and release 6.7 wt.% hydrogen within 60 s and 10 min at 300 oC, respectively, and exhibits excellent cycling stability and low-temperature hydrogen storage performance. This study provides a strategy for designing efficient catalysts for hydrogen storage materials using the synergy of metal elements.

Research Article Issue
Boosting electrocatalytic water splitting via metal-metalloid combined modulation in quaternary Ni-Fe-P-B amorphous compound
Nano Research 2020, 13 (2): 447-454
Published: 16 January 2020

Design and synthesis of highly efficient and cost-effective bifunctional catalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) remain a big challenge. Herein, a quaternary amorphous nanocompound Ni-Fe-P-B has been synthesized by a facile, scalable co-reduction method. The Ni-Fe-P-B exhibits high electrocatalytic activity and outstanding durability for both HER and OER, delivering a current density of 10 mA·cm-2 at overpotentials of 220 and 269 mV, respectively. When loaded on carbon fiber paper (CFP) as a bifunctional catalyst, the Ni-Fe-P-B@CFP electrode requires a low cell voltage of 1.58 V to obtain 10 mA·cm-2 for overall water splitting with negligible recession over 60 h. The excellent catalytic performances of Ni-Fe-P-B mainly benefit from the metal-metalloid combined composition modulation and the unique amorphous structure. This work provides new insights into the design of robust bifunctional catalysts for water splitting, and may promote the development of multicomponent amorphous catalysts.

Research Article Issue
Yolk–shell structured Co-C/Void/Co9S8 composites with a tunable cavity for ultrabroadband and efficient low-frequency microwave absorption
Nano Research 2018, 11 (8): 4169-4182
Published: 12 February 2018

A yolk–shell structured Co-C/Void/Co9S8 ternary composite composed of a Co nanoparticle-embedded porous carbon core and Co9S8 shell was synthesized by the sulfidation of a Co-based zeolitic imidazolate framework and subsequent pyrolysis. The composition and interior cavity of the Co-C/Void/Co9S8 composite could be precisely modulated by controlling the sulfidation reaction. Due to the abundant heterointerfaces, well-controlled cavity, and magnetic–dielectric synergistic effects, the Co-C/Void/Co9S8 exhibited excellent and tunable microwave-absorbing properties. The optimized Co-C/Void/Co9S8, having a loading of 25 wt.% and thickness only 2.2 mm, displayed an ultrabroad absorption bandwidth of 8.2 GHz at high frequencies. Moreover, the composite could achieve an extremely high reflection loss of–54.02 dB at low frequencies by adjusting its loading to 30 wt.%. This study provides a new insight into promising lightweight microwave-absorbing materials with ultrabroad absorption bandwidths and strong low-frequency absorption.

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