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Zeolites have been recognized as one type of the most promising adsorbents for capturing volatile organic compounds (VOCs, e.g., toluene), but their performance suffers severely from water vapor under wet conditions. In this contribution, we demonstrated that the hydrophobicity of microporous zeolites can be significantly improved by coating vertically aligned LDH nanoplatelets when the contact angle is increased from 16.5−20.1°to 44.4−64.2°. The toluene adsorption capacity of such synthesized zeolite@ LDH core@shell composites in wet conditions can thus be largely enhanced when the breakthrough time is increased from 6.4−10.8 to 20.1−27.5 min.

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A series of CuCo 2 O 4 composite spinels with an interconnected meso-macroporous nanosheet morphology were synthesized using the hydrothermal method and subsequent calcination treatment to activate peroxymonosulfate (PMS) for benzophenone-4 (BP-4) degradation. As-prepared CuCo 2 O 4 composite spinels, especially CuCo-H3 prepared by adding cetyltrimethylammonium bromide, showed superior reactivity for PMS activation. In a typical reaction, BP-4 (10.0 mg/L) was almost completely degraded in 15 min by the activation of PMS (200.0 mg/L) using CuCo-H3 (100.0 mg/L), with only 9.2 μg/L cobalt leaching detected. Even after being used six times, the performance was not influenced by the lower leaching of ions and surface-absorbed intermediates. The possible interface mechanism of PMS activation by CuCo-H3 was proposed, wherein a unique interconnected meso-macroporous nanosheet structure, strong interactions between copper and cobalt, and cycling of Co(II)/Co(III) and Cu(I)/Cu(II) effectively facilitated PMS activation to generate SO 4•− and • OH, which contributed to BP-4 degradation. Furthermore, combined with intermediates detected by liquid chromatography quadrupole time-of-flight mass spectrometry and density functional theory calculation results, the degradation pathway of BP-4 involving hydroxylation and C−C bond cleavage was proposed.

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