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TiO2/SiO2-Based nanocomposites with highly porous structures have received increasing attention due to their excellent photocatalytic activity. In this work, a TiO2/SiO2/Ag ternary composite aerogel with enhanced visible-light photocatalytic activity has been successfully synthesized through a facile sol–gel method combined with a supercritical drying technique. The specific surface area and pore structure of TiO2/SiO2/Ag aerogel could be controlled by adjusting the Si content. The TiO2/SiO2/Ag aerogel with pore size of 9.2 nm achieved the maximum adsorption capacity of oxytetracycline. The presence of SiO2 in TiO2/SiO2/Ag improved the compression strength of the aerogel and thus achieved long-term stability in photocatalysis. Furthermore, the addition of Ag particles in TiO2/SiO2/Ag effectively decreased the recombination of photo-electrons and holes. The photocatalytic degradation rates of oxytetracycline over the TiO2/SiO2/Ag aerogel with a mole ratio of Ag : Si : Ti = 0.1 : 10 : 4 were 3.1 and 2.3 times those over P25 and a TiO2/SiO2 aerogel. The enhanced photocatalytic performance of the TiO2/SiO2/Ag aerogel is attributed to the large specific surface area, 3-D porous structure, high electrical conductivity and compression strength of this novel composite aerogel. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • In 1−x Zn x O y heterogeneous NFs with mixed phases of c- and rh-In 2 O 3 are fabricated. • Rh-In 2 O 3 phase improves electrical conductivity and optimizes interface interplay. • Phase compositions of rh-In 2 O 3 and c-In 2 O 3 can be controllably tuned. • Excellent performance is attributed to the phase composition and interfaces. Abstract Poor cyclability and rate performance are two key problems hindering the practical application of In 2 O 3 in high power lithium-ion batteries. Herein, we report a phase transition strategy to fabricate novel In 1−x Zn x O y heterogeneous nanofibers with mixed phases of cubic bixbyite-type In 2 O 3 and rhombohedral corundunm-type In 2 O 3 to enhance the lithium ion storage ability. The one-dimensional structure shortens the path for lithium ion diffusion and electron transfer, and accommodates the large volume changes upon cycling. The introduction of rhombohedral corundunm-type In 2 O 3 can favorably improve the electrical conductivity, provide more pathways for lithium ion diffusion, and optimize the interface interplay. The optimal In 0.5 Zn 0.5 O 1.25 heterogeneous nanofibers exhibit superior cyclic stability and outstanding high-rate performance, which can be ascribed to the synergistic effects of excellent electrical conductivity, more pathways for lithium ion diffusion, and the coupling effect of heterogeneous interface. This new phase-transition induced formation of heterostructure nanofibers is enlightening in design high performance electrode materials for lithium ion batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • SAM aerogel is prepared by directional freeze-drying method. • Tuning carbonization temperature and activator ratio to optimize performance. • SAM-700-4 shows 3D interconnected structure with large specific surface area. • SAM-700-4 shows excellent specific capacitance of 441.80 F/g at 0.5 A/g. • SAM-700-4//SAM-700-4 all-solid-state supercapacitor exhibit high energy density. Hierarchical porous carbon shows great potential in the field of energy storage due to high porosity, large surface area, and excellent electrical conductivity. Here, we successfully fabricated carbon aerogel derived from sodium alginate/melamine composite (SAM) by directional freeze-drying combined with simple carbonization and activation process. The optimal SAM-700-4 possesses a high nitrogen (5.67 at.%) and oxygen (8.98 at.%) contents along with high specific surface area of 2577.62 m2/g and unique directional channel structure. Due to their synergistic effect, the SAM-700-4 electrode exhibits a high specific capacitance of 441.80 F/g at a current density of 0.5 A/g. Interestingly, the all-solid-state symmetric supercapacitor based on SAM-700-4//SAM-700-4 in PVA/SA/KOH gel electrolyte has a large energy density of 20.87 Wh/kg at a power density of 4000 W/kg and exhibits excellent cycling stability. It is believed that this N, O co-doped directional hierarchical porous carbon aerogel may show promising prospects as advanced energy storage materials. [ABSTRACT FROM AUTHOR]