Department of Chemical Engineering, Indian Institute of Technology Gandhinagar, Gujarat-382355, India.
Phys Chem Chem Phys. 2019 Feb 6;21(6):3164-3173. doi: 10.1039/c8cp06766j.
The classic Belousov-Zhabotinsky (BZ) reaction, which involves transition metal catalysed redox reactions, represents a family of nonlinear chemical oscillators. Here, we show that it is possible to tune the oscillatory dynamics of the BZ reaction by using a hybrid 2D material, i.e., graphene-based nanosheets decorated with Ru nanoparticles. Specifically, we demonstrate that the frequency of chemical oscillations in a BZ reaction increases, by up to four-fold, when catalyzed by the Ru-graphene nanocomposite. We show that this observed behaviour is attributed to enhanced access to active catalytic sites on Ru nanoparticles, as well as the rapid shuttling of electrons facilitated by the highly conductive graphene platform. We further demonstrate that this enhancement of oscillations facilitated by the graphene platform can be simulated using the Oregonator model. Our numerical simulations reveal a strong correlation between the rate of charge transfer and the frequency of chemical oscillations. This ability of a 2D material, like graphene, to influence the dynamics of an oscillatory chemical reaction, as showcased in this work, is studied for the first time and opens up new avenues to tune the dynamics of chemical oscillators. We anticipate that these findings would enable us to design a variety of intrinsically powered biomimetic systems with controllable dynamic behavior.
经典的 Belousov-Zhabotinsky(BZ)反应涉及过渡金属催化的氧化还原反应,代表了一类非线性化学振荡器。在这里,我们展示了通过使用混合 2D 材料,即负载 Ru 纳米粒子的石墨烯基纳米片,可以调节 BZ 反应的振荡动力学。具体来说,我们证明了当被 Ru-石墨烯纳米复合材料催化时,BZ 反应的化学振荡频率可以增加高达四倍。我们表明,这种观察到的行为归因于对 Ru 纳米粒子上活性催化位点的增强访问,以及石墨烯平台促进的电子的快速穿梭。我们进一步证明,石墨烯平台促进的这种振荡增强可以使用 Oregonator 模型进行模拟。我们的数值模拟揭示了电荷转移速率与化学振荡频率之间的强相关性。这种像石墨烯这样的 2D 材料影响振荡化学反应动力学的能力,如本工作所示,是首次进行研究的,为调节化学振荡器的动力学开辟了新途径。我们预计这些发现将使我们能够设计具有可控动态行为的各种内在动力仿生系统。