Determination of surface electronic states of solids in solution by means of charge transfer reaction inverse photoemission spectroscopy (CTRIPS).

采用两种实验方法研究了金属/电解质界面上电子转移反应引起的光子发射的细节：第一种方法是在含有氧化还原物种的溶液中进行测量;电位阶跃到负电位U_i。其中氧化还原物种转化为阴离子自由基，然后转化为各种正电位U_f，其中阴离子自由基被氧化。研究了电极金属（Au、Pt和Pd）和氧化还原物种（苯甲腈.二苯乙烯和二苯甲酮）对发光性能的影响。光谱的高能量阈值E_<th>与电极电位U_f成线性关系，几乎等于-e（U_f-U_f），其中U_f是化学物种的氧化还原电位。谱的峰位E_p也依赖于U_f和U_p，但不太敏感。虽然E_p<th>仅由U_f和U_p决定，但E_p具有金属依赖性。排放效率。PHI，单位： ...更多信息 随着U_f变得更正，增加，饱和，然后减小。PHI的电位依赖性还取决于金属的选择。在此基础上，考虑了几种可能的光子发射机制，认为光子发射的主要贡献是涉及体能带态的电荷转移反应逆光电子发射（CTRIP）过程。当电极电势变为正时，发射光的效率急剧增加。当电极电势变为正的1 eV/V时，光谱的高能量阈值也增加。当电极电势变为正的时，峰值能量也正向移动，尽管移动的程度小得多。各种过程被认为是光子发射的可能机制。通过对铂电极和金电极上结果的定性比较，提出了电化学体系中逆光电发射过程对发光过程中体带态的贡献。将这种现象应用于一种新的光谱学的可行性进行了讨论。也得到了溶剂化电子的电子态信息。少

The details of the photon emission at metal/electrolyte interfaces induced by an electron transfer reaction was investigated by employing two experimental procedures.In the first method, the measurements were carried out in solutions containing some redox species. The potential was stepped to a negative potential, U_i. where the redox species is converted to as anion radical, and then to various positive potentials, U_f, where the anion radical is oxidized. The effects of electrode metals (Au, Pt and Pd) and redox species (benzonitrile. tstilbene and benzophenone) on emission properties were studied. The high energy threshold of the spectrum, E_<th>, changes linearly with the electrode potential, U_f, and is almost equal to -e (Uﾟ-U_f) where Uﾟis the redox potential of the chemical species. The peak position of the spectrum, E_p, also depends though less sensitively on U_f and Uﾟ. Although E_<th> is solely determined by U_f and Uﾟ, E_p has metal dependence. Emission efficiency. PHI, in … More creases, saturates and then decreases as U_f becomes more positive. The potential dependence of PHI also depends on the choice of metal. Based on these results, several possible mechanisms for the photon emission are considered and it is concluded that the major contribution to the photon emission is the charge transfer reaction inverse photoemission (CTRIP) process involving bulk band states.In the second method, solvated electrons were used as electron injecting spesies and the electrode potential was kept constant. The efficiency of emitted light increases drastically as the electrode potential becomes positive. The high energy threshold of the spectrum also increases as the electrode potential becomes positive by 1 eV/V. The peak energy also shifts positively as the electrode potential becomes positive, although the degree of the shift is much smaller. Various processes are considered as a possible mechanism for a photon emission. From the qualitative comparison of the results at plantinum and gold electrode, the contribution of the inverse photoemission process to thebulk band states at the light emission process in the electrochemical system is suggested. The feasibility of applying this phenomenon to a novel spectroscopy is discussed. Information on electronic states of solvated electrons was also obtained. Less