As Co₃O₄ is one of the most attractive catalysts for H₂ generation (HG) from NaBH₄ hydrolysis, Co₃O₄ nanoparticle (NP)-immobilized composites are intensively developed for NaBH₄ hydrolysis. Nevertheless, these Co₃O₄ composites involve complicated fabrication procedures and long preparation time. More importantly, these composites typically consist of a large fraction of “dead” weight of inactive substrates, causing these composites unnecessarily effective. Unlike immobilizing Co₃O₄ NPs on substrates, this study proposes a Co₃O₄ catalyst completely comprised of Co₃O₄ NPs which are framed but the entire Co₃O₄ catalyst can still exhibit porosity. To this end, a cobaltic zeolitic imidazolate framework (ZIF-67) with morphology of rhombic dodecahedron is adopted as a templated precursor, which is converted into Co₃O₄ rhombic dodecahedral (RD) granule. Because of cobaltic species and hierarchical structures of ZIF-67, the resulting Co₃O₄ RD granule can consist of densely packed Co₃O₄ NPs, but remain porous, making it a promising catalyst for NaBH₄ hydrolysis. This ZIF-67 derived Co₃O₄ (ZIFCoO) exhibits a considerably higher catalytic activity than its precursors, ZIF-67 and carbonized ZIF-67, as well as the commercial Co₃O₄ NPs. While a higher dose of ZIFCoO facilitates NaBH₄ hydrolysis to generate more H₂, 500 mg/L of ZIFCoO is the optimal catalyst dose to obtain the highest HG rate. ZIFCoO also exhibits a relatively low E_a as 39.4 kJ/mol compared to most of the reported catalysts. ZIFCoO can be also reused for multiple cycles of HG efficiently. These features make ZIFCoO a conveniently-prepared and promising heterogeneous catalyst for H₂ generation from NaBH₄ hydrolysis.

由于Co ₃ O ₄是NaBH ₄水解产生H ₂的最有吸引力的催化剂（HG）之一，因此大力开发了Co ₃ O ₄纳米粒子（NP）固定的复合材料用于NaBH ₄水解。然而，这些Co ₃ O ₄复合材料涉及复杂的制造过程和长的制备时间。更重要的是，这些复合材料通常由很大一部分“无用”重量的惰性基材组成，从而导致这些复合材料不必要地有效。与将Co ₃ O ₄ NPs固定在基质上不同，本研究提出了Co ₃ O_4种催化剂完全由带框的Co ₃ O ₄ NP组成，但整个Co ₃ O ₄催化剂仍可显示出孔隙度。为此，采用具有菱形十二面体形态的钴沸石咪唑酸盐骨架（ZIF-67）作为模板化前体，将其转化为Co ₃ O ₄菱形十二面体（RD）颗粒。由于ZIF-67的钴物种和分层结构，所得的Co ₃ O ₄ RD颗粒可以由致密堆积的Co ₃ O ₄ NP组成，但仍保持多孔状态，使其成为有希望的NaBH ₄催化剂水解。这种ZIF-67衍生的Co ₃ O ₄（ZIFCoO）表现出比其前体ZIF-67和碳化ZIF-67以及市售Co ₃ O ₄ NP更高的催化活性。尽管较高的ZIFCoO剂量有助于NaBH ₄水解生成更多的H ₂，但500 mg / L的ZIFCoO是获得最高HG速率的最佳催化剂剂量。与大多数报道的催化剂相比，ZIFCoO还显示出相对较低的E _a，为39.4 kJ / mol。ZIFCoO还可以有效地用于HG的多个循环。这些特性使ZIFCoO成为可方便制备且很有前景的NaBH生成H _2的非均相催化剂₄水解。