One-Step Synthesis of Carbon-Hybridized ZnO on Polymeric Foams by Atomic Layer Deposition for Efficient Absorption of Oils from Water

Reusable absorbents with high absorption capacity, good selectivity, and low cost are highly demanded for efficient removal of oil spills and organic leakages from water. We discover that ZnO produced by atomic layer deposition (ALD) is hybridized with carbon moieties, and consequently exhibits an appreciable hydrophobicity. By taking this advantage, we develop a "dry" process to produce high-performance oil absorbents. Originally amphiphilic polymeric foams are directly turned into strongly hydrophobic oil absorbents simply by ALD of ZnO and exhibit excellent absorption capacity, selectivity and reusability. Such absorption capacities and reusability are better than most foam-based oil absorbents. Surprisingly, we find that ALD-deposited ZnO can reverse the wettability of polymeric foams depending on the foam porosities. This ALD-enabled surface functionalization is expected to find important applications in the synthesis of many other interfacial materials.