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至今为止所报道的对固体表面原子水平的研究几乎毫无例外的局限在单晶表面。其主要原因之一是存在着在多晶或粗糙表面上获得原子分辨ＳＴＭ图象的困难性。尽管如此，由于多晶材料是更为普遍、更切实际的进行各种物理和化学过程的场所，若能实现多晶或粗糙表面的原子水平的观察，其研究意义和前景将大为拓宽。本文报道在含氯化钾的电化学体系中极端条件下金（１１１）面和多晶金表面结构的原子水平的ＳＴＭ观察。图一为Ａｕ（１１１）面在不同条件下的电化学现场ＳＴＭ图。在４００～－４００ｍＶ电位区间内Ａｕ（１１１）保持稳定的（１ｘ１）结构，未观察到来自于Ａｕ表面的重构或Ｃｌ－吸附层结构。当电位负移至－６００以内，尽管此时金电极仍处于双电层区，Ａｕ表面已出现一定程度的粗糙。有趣的是，当电位经过１．０Ｖ后返回至０Ｖ时，大范围的ＳＴＭ图象显示了由原子台阶构成的孔洞和原子平整的晶面共成的情形。图二为空气下得到的金多晶的表面形貌（Ａ）和原子分辨表面结构（Ｂ）的ＳＴＭ图。分析图二（Ｂ）和（Ｃ）可以得知，图中两亮点之间的平均距离为０．４ｎｍ，可以排除原子簇结构的可能。可以确定这些具有一定取向的亮点为原子阵列，而较大的原子间距正反应了多晶表面与本体结构的不同之?
So far reported on the solid surface atomic level almost no exception to the single-crystal surface. One of the main reasons for this is the difficulty of obtaining atomically resolved STM images on polycrystalline or rough surfaces. Nonetheless, as polycrystalline materials are more prevalent and more practical places to conduct a variety of physical and chemical processes, their implications and prospects for broadening the atomic level of polycrystalline or rough surfaces can be broadened. This paper reports the STM observation of the atomic level of the gold (111) surface and the polycrystalline gold surface under extreme conditions in an electrochemical system containing potassium chloride. Figure 1 shows the electrochemistry field STM of Au (111) under different conditions. Au (111) remained stable (1x1) within 400 ~ -400mV potential range, and no remodeling or Cl-adsorbed layer structure from Au surface was observed. When the potential negative shift to -600 or less, although at this time the gold electrode is still in the electric double layer, Au surface has a certain degree of roughness. Interestingly, when the potential returns to 0V after passing 1.0V, a wide range of STM images show the coexistence of voids formed by atomic steps and atomically flat crystal planes. Figure 2 shows the surface morphology (A) and atomic resolution surface structure (B) of gold polygons obtained under the STM diagram. Analysis of Figure 2 (B) and (C) shows that the average distance between two bright spots in the figure is 0.4nm, which can eliminate the possibility of cluster structure. Can determine these bright spots with a certain orientation for the atomic array, and a larger atomic spacing is the polycrystalline surface and the body structure is different?