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Sodium-ion batteries (SIBs) are promising alternatives to lithium-ion batteries (LIBs) in view of the natural abundance and low cost of sodium resource. Constructing high-performance anode is essential and challenging for the futuristic SIBs development. Transition metal sulfides have been proved as promising anode materials for SIBs due to their large specific capacities. Here, in situ assembly of cobalt sulfide nanosheets on stainless steel mesh (SSM/CoS) as a binder-free anode for SIBs is carried out through a facile electrochemical deposition procedure. The SSM/CoS products are directly used as anode electrodes without addition of binder and conductive additives. As a result, a high capacity of 313 mAh g−1 is obtained at a current density of 50 mA g−1 over 100 cycles.

Carbon nanotube/graphene foam/silicon carbide (CNT/GF/SiC) composites are prepared by in-situ growth of CNT in GF and followed by infiltration and pyrolysis of CNT-dispersed polycarbosilane. Results show that the CNT/GF/SiC composites exhibit outstanding electromagnetic interface (EMI) shielding effectiveness (SE) of 32.1 dB in X-band, especially the specific SE reaches up to 33.8 dB cm3/g with a low density of 0.95 g/cm3. The interconnected conductive graphene network improves the conductivity and sharply increases electric loss; meanwhile, the rich structural defects and multiscale interfaces including GF-CNT interface and CNT-SiC interface offer additional polarization loss, both of which endow composites with outstanding EMI shielding performance.

Owing to the rich abundance and low-cost of K resources, potassium-ion batteries (KIBs) have been a promising alternative to lithium-ion batteries (LIBs). The exploration of suitable anode materials is challenging but of great importance for KIBs development. Alloying anodes such as Sn, Sb and their oxides have been proved as promising anode materials for KIBs due to their high specific capacities. Here, Sn nanoparticles uniformly anchored on N doped porous carbon (Sn/NPC) are prepared using simple sol-gel method and heat treatment. As support skeleton, NPC endows Sn/NPC good conductivity and prevent agglomeration of Sn nanoparticles, which can be beneficial for high capability and rate performance. When evaluated as anode of KIBs, enhanced capacity of 198 mAh g−1 is achieved at a current density of 50 mA g−1 after 200 cycles.