论文标题
了解硒的强度 - 石墨烯界面
Understanding the Strength of the Selenium -- Graphene Interfaces
论文作者
论文摘要
我们提出了综合的第一原理密度功能理论（DFT）分析，对晶体强度和晶体和无定形硒（SE）之间的界面强度和粘结机制（GR）（GR），这是一种有前途的储存储能二人组。比较界面分析在用石墨烯和铝（Al）底物的石墨烯和晶体SE上列出在无定形硅（SI）上。用石墨烯（0.41 j/m2）的单斜se（0.43 j/m2）和无定形Si的界面强度在幅度上相似。尽管两种材料（C-SE，A-SI）均由石墨烯上的范德华（VDW）力松散地粘合，但对于A-SI/GR，界面电子交换较高。通过比较跨石墨烯界面的势能步骤和电荷转移（Delta Q），可以进一步阐述这一点。 C-SE/GR和A-SI/GR的增量Q分别为0.3119 E-1和0.4266 E-1。但是，3D Al底物上C-SE的界面强度较高（0.99 J/m2），表明粘附更强。用石墨烯的无定形SE具有可比的界面强度（0.34 j/m2），但是该系统中的电子交换与单斜晶型SE略有不同。对于单斜胶和非晶态SE，电子特性（状态分析的密度）和键合机制是不同的，并且它们通过表面电荷掺杂掺杂，它们通过表面电荷激活石墨烯。我们的发现突出了SE中与石墨烯相连的复杂电化学现象，这可能与它们的“自由”对应物有很大不同。
We present a comprehensive first-principles Density Functional Theory (DFT) analyses of the interfacial strength and bonding mechanisms between crystalline and amorphous selenium(Se) with graphene(Gr), a promising duo for energy storage applications. Comparative interface analyses are presented on amorphous silicon(Si) with graphene and crystalline Se with aluminum(Al) substrate. The interface strength of monoclinic Se (0.43 J/m2) and amorphous Si with graphene (0.41 J/m2) is similar in magnitude. While both materials (c-Se, a-Si) are bonded loosely by van der Waals (vdW) forces over graphene, interfacial electron exchange is higher for a-Si/Gr. This is further elaborated by comparing potential energy step and charge transfer (delta q) across the graphene interfaces. The delta q for c-Se/Gr and a-Si/Gr are 0.3119 e-1 and 0.4266 e-1, respectively. However, the interface strength of c-Se on the 3D Al substrate is higher (0.99 J/m2), suggesting stronger adhesion. The amorphous Se with graphene has comparable interface strength (0.34 J/m2), but electron exchange in this system is slightly distinct from monoclinic Se. The electronic characteristics (density of states analysis) and bonding mechanisms are different for monoclinic and amorphous Se with graphene and they activate graphene via surface charge doping divergently. Our findings highlight the complex electrochemical phenomena in Se interfaced with graphene, which may profoundly differ from their 'free' counterparts.
