Development of sorbent materials with high selectivity and sorption capacity, easy collection and recyclability is demanding for spilled oil recovery. Although many sorption materials have been proposed, a systematic study on how they can be reused and possible performance degradation during regeneration remains absent. Here we report magnetic carbon nanotube sponges (Me-CNT sponge), which are porous structures consisting of interconnected CNTs with rich Fe encapsulation. The Me-CNT sponges show high mass sorption capacity for diesel oil reached 56 g/g, corresponding to a volume sorption capacity of 99%. The sponges are mechanically strong and oil can be squeezed out by compression. They can be recycled using through reclamation by magnetic force and desorption by simple heat treatment. The Me-CNT sponges maintain original structure, high capacity, and selectivity after 1000 sorption and reclamation cycles. Our results suggest that practical application of CNT macrostructures in the field of spilled oil recovery is feasible.

Efficient use of precious metal atoms in heterogeneous catalysis is important in chemical transformation and environmental remediation. Co3O4 with singly dispersed Rh atoms, Rh1/Co3O4, was synthesized for reduction of nitric oxide with hydrogen. Studies using extended X-ray absorption fine structure (EXAFS) showed that the singly dispersed Rh atoms are bonded to surface oxygen atoms before catalysis. In situ studies using ambient pressure X-ray photoelectron spectroscopy (AP-XPS), EXAFS, and X-ray Absorption Near Edge Structure (XANES) suggested that the surface of Rh1/Co3O4 with singly dispersed Rh atoms is restructured into a new geometry at 220 °C in the mixture of reactant gases (NO and H2). It forms RhCo n nanoclusters singly dispersed in the surface layer of Co3O4. The restructured catalyst, RhCo n /Co3O4 exhibits a much better catalytic performance in contrast to Rh1/Co3O4 without a restructuring. RhCo n /Co3O4 is highly active for reduction of nitric oxide with hydrogen. Selectivity to the production of N2 at 220 °C is 87% and reaches 97% at 300 °C. In situ studies showed this catalyst maintains its single dispersion of Rh atoms up to 300 °C during catalysis.

Rotatable spacer increases the motions of ionic side-chain to accelerate both ion and H2O transport during fuel cell operation.