Precise spatial control of 2D materials is the key capability of engineering their optical, electronic, and mechanical properties. However, growth of novel 2D Mo2C on Cu surface by chemical vapor deposition method was revealed to be seed-induced 2D growth, limiting further synthesis of complex Mo2C spatial structures. In this research, we demonstrate the controlled growth of Mo2C pyramids with numerous morphologies, which are characterized with clear terraces within the structures. The whole evolution for Mo2C pyramids in the coursed of CVD process has been detected, posing significant potential in probing growth mechanism. The formation of the Mo2C pyramids arises from the supersaturation-induced nucleation and concentration-gradient driven diffused growth of a new Mo2C layer on the edged areas of intrinsic ones, as supported by STEM imaging. This work provides a novel Mo2C-based pyramid structure and further reveals a sliding growth mechanism, which could offer impetus for the design of new 3D spatial structures of Mo2C and other 2D materials.

中文翻译：

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液态铜表面上 Mo2C 金字塔的受控生长

二维材料的精确空间控制是设计其光学、电子和机械性能的关键能力。然而，通过化学气相沉积方法在 Cu 表面上生长的新型 2D Mo2C 被证明是种子诱导的 2D 生长，限制了复杂 Mo2C 空间结构的进一步合成。在这项研究中，我们展示了具有多种形态的 Mo2C 金字塔的受控生长，其特征在于结构内具有清晰的阶地。已检测到在 CVD 过程中 Mo2C 金字塔的整个演变过程，在探索生长机制方面具有重要潜力。Mo2C 金字塔的形成源于过饱和诱导的成核和浓度梯度驱动的新 Mo2C 层在固有层边缘区域的扩散生长，这得到了 STEM 成像的支持。