Swathi R S, Sebastian K L
Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India.
J Chem Phys. 2008 Aug 7;129(5):054703. doi: 10.1063/1.2956498.
We study the distance dependence of the rate of resonance energy transfer from the excited state of a dye to the pi system of graphene. Using the tight-binding model for the pi system and the Dirac cone approximation, we obtain the analytic expression for the rate of energy transfer from an electronically excited dye to graphene. While in traditional fluorescence resonance energy transfer, the rate has a (distance)(-6) dependence, we find that the distance dependence in this case is quite different. Our calculation of rate in the case of the two dyes, pyrene and nile blue, shows that the distance dependence is Yukawa type. We have also studied the effect of doping on energy transfer to graphene. Doping does not modify the rate for electronic excitation energy transfer significantly. However, in the case of vibrational transfer, the rate is found to be increased by an order of magnitude due to doping. This can be attributed to the nonzero density of states at the Fermi level that results from doping.
我们研究了从染料的激发态到石墨烯π体系的共振能量转移速率的距离依赖性。利用π体系的紧束缚模型和狄拉克锥近似，我们得到了从电子激发染料到石墨烯的能量转移速率的解析表达式。在传统的荧光共振能量转移中，速率具有（距离）^（-6）依赖性，而我们发现这种情况下的距离依赖性有很大不同。我们对芘和尼罗蓝这两种染料情形下的速率计算表明，距离依赖性是汤川型的。我们还研究了掺杂对向石墨烯能量转移的影响。掺杂对电子激发能量转移的速率没有显著改变。然而，在振动转移的情形下，发现由于掺杂速率增大了一个数量级。这可归因于掺杂导致的费米能级处非零的态密度。
