The National Institute for Materials Science, Advanced Materials Laboratory , 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
ACS Nano. 2015 Oct 27;9(10):10347-55. doi: 10.1021/acsnano.5b04443. Epub 2015 Sep 14.
The fluorescence of a two-dimensional supramolecular network of 5,10,15,20-tetrakis(4-carboxylphenyl)porphyrin (TCPP) adsorbed on hexagonal boron nitride (hBN) is red-shifted due to, primarily, adsorbate-substrate van der Waals interactions. TCPP is deposited from solution on hBN and forms faceted islands with typical dimensions of 100 nm and either square or hexagonal symmetry. The molecular arrangement is stabilized by in-plane hydrogen bonding as determined by a combination of molecular-resolution atomic force microscopy performed under ambient conditions and density functional theory; a similar structure is observed on MoS2 and graphite. The fluorescence spectra of submonolayers of TCPP on hBN are red-shifted by ∼30 nm due to the distortion of the molecule arising from van der Waals interactions, in agreement with time-dependent density functional theory calculations. Fluorescence intensity variations are observed due to coherent partial reflections at the hBN interface, implying that such hybrid structures have potential in photonic applications.
吸附在六方氮化硼（hBN）上的 5,10,15,20-四（4-羧基苯基）卟啉（TCPP）二维超分子网络的荧光由于吸附剂-衬底范德华相互作用而发生红移。TCPP 从溶液中沉积在 hBN 上，并形成具有典型尺寸为 100nm 的具有正方形或六边形对称性的有角岛。分子排列通过在环境条件下进行的分子分辨率原子力显微镜和密度泛函理论的组合确定的面内氢键来稳定；在 MoS2 和石墨上也观察到类似的结构。由于范德华相互作用引起的分子变形，hBN 上 TCPP 的亚单层的荧光光谱红移了约 30nm，这与时间相关的密度泛函理论计算结果一致。由于 hBN 界面处的相干部分反射，观察到荧光强度变化，这意味着这种混合结构在光子学应用中具有潜力。
