Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, Beijing Key Laboratory of Bio-inspired Energy Materials and Devices, School of Chemistry and Environment, Beihang University , Beijing 100191, P. R. China.
ACS Nano. 2016 Apr 26;10(4):4816-27. doi: 10.1021/acsnano.6b01752. Epub 2016 Apr 14.
In nacre, the excellent mechanical properties of materials are highly dependent on their intricate hierarchical structures. However, strengthening and toughening effects induced by the buried inorganic-organic interfaces actually originate from various minerals/ions with small amounts, and have not drawn enough attention yet. Herein, we present a typical class of artificial nacres, fabricated by graphene oxide (GO) nanosheets, carboxymethylcellulose (CMC) polymer, and multivalent cationic (M(n+)) ions, in which the M(n+) ions cross-linking with plenty of oxygen-containing groups serve as the reinforcing "evocator", working together with other cooperative interactions (e.g., hydrogen (H)-bonding) to strengthen the GO/CMC interfaces. When compared with the pristine GO/CMC paper, the cross-linking strategies dramatically reinforce the mechanical properties of our artificial nacres. This special reinforcing effect opens a promising route to strengthen and toughen materials to be applied in aerospace, tissue engineering, and wearable electronic devices, which also has implication for better understanding of the role of these minerals/ions in natural materials for the mechanical improvement.
在珍珠层中，材料的优异机械性能高度依赖于其错综复杂的层次结构。然而，由少量埋入的无机-有机界面引起的增强和增韧效果实际上源于各种具有少量的矿物质/离子，并且尚未引起足够的重视。在此，我们提出了一类典型的人工珍珠层，由氧化石墨烯 (GO) 纳米片、羧甲基纤维素 (CMC) 聚合物和多价阳离子 (M(n+)) 离子制成，其中与大量含氧基团交联的 M(n+) 离子作为增强“唤起者”，与其他协同相互作用（例如氢键）一起增强 GO/CMC 界面。与原始 GO/CMC 纸相比，交联策略极大地增强了我们人工珍珠层的机械性能。这种特殊的增强效果为增强和增韧材料开辟了一条有前途的途径，可应用于航空航天、组织工程和可穿戴电子设备，这也有助于更好地理解这些矿物质/离子在天然材料中对机械性能提升的作用。
