An apparatus for preparing frozen solution samples in ultrahigh vacuum experiments.

Area of Science:

• Surface science
• Materials science
• Physical chemistry

Background:

• Characterizing solution samples under ultrahigh vacuum (UHV) conditions presents significant challenges.
• Existing methods often struggle to maintain sample integrity and cleanliness during transfer to UHV environments.

Purpose of the Study:

• To develop a novel apparatus for preparing and transferring frozen solution samples into UHV.
• To enable in situ surface science characterization of solution crystallization and related phenomena.

Main Methods:

• A temperature-controlled substrate makes contact with a frozen solution at 77 K, causing local melting and refreezing.
• In situ cleavage and transfer of the frozen solution onto the substrate within a high vacuum environment.
• Atomic force microscopy (AFM) in UHV at 5 K for atomic-resolution imaging.

Main Results:

• Successfully transferred frozen NaCl and LiNO3 solutions onto an Au substrate.
• Directly imaged the crystallization of NaCl and LiNO3 with atomic resolution using AFM in UHV.
• Demonstrated the apparatus's capability to maintain sample cleanliness and glassy states.

Conclusions:

• The developed apparatus offers a new pathway for transferring solution samples into UHV.
• This technique facilitates fundamental research into crystallization, hydration, and chemical reactions in solution.
• Lays the groundwork for advanced applications in materials synthesis and bioimaging.