Hefei National Laboratory for Physical Sciences at the Microscale, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Hefei Science Center (CAS) and CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science & Technology of China, Hefei, 230026, PR China.
CAS Key Lab of Materials for Energy Conversion, Department of Materials Science and Engineering, University of Science & Technology of China, Hefei, 230026, PR China.
Angew Chem Int Ed Engl. 2016 Feb 24;55(9):3176-80. doi: 10.1002/anie.201511436. Epub 2016 Jan 28.
The graphene system is actively pursued in spintronics for its nontrivial sp electron magnetism and its potential for the flexible surface chemical tuning of magnetoelectronic functionality. The magnetoresistance (MR) of graphene can be effectively tuned under high magnetic fields at cryogenic temperatures, but it remains a challenge to achieve sensitive magnetoelectric response under ambient conditions. We report the use of surface modulation to realize superparamagnetism in reduced graphene oxide (rGO) with sensitive magnetic field response. The superparamagnetic rGO was obtained by a mild oxidation process to partially remove the thiol groups covalently bound to the carbon framework, which brings about large low-field negative MR at room temperature (-8.6 %, 500 Oe, 300 K). This strategy provides a new approach for optimizing the intrinsic magnetoelectric properties of two-dimensional materials.
在自旋电子学中，石墨烯系统因其非平凡的 sp 电子磁性及其在柔性表面化学调控磁电子功能方面的潜力而受到广泛关注。在低温下，通过强磁场可以有效地调节石墨烯的磁电阻（MR），但在环境条件下实现灵敏的磁电响应仍然是一个挑战。我们报告了使用表面调制来实现还原氧化石墨烯（rGO）中的超顺磁性，以及其对磁场的灵敏响应。通过温和的氧化过程部分去除与碳骨架共价结合的巯基，得到超顺磁 rGO，从而在室温下产生大的低场负磁电阻（-8.6%，500 Oe，300 K）。该策略为优化二维材料的固有磁电性能提供了一种新途径。
