Scanning Tunneling and Atomic Force Microscope

EMSL's Molecular Imaging, Inc. PicoSPM™ scanning tunneling microscopy (STM)/atomic force microscopy (AFM) supports a wide range of scanning-probe techniques used to examine surfaces of diverse materials such as conductive and nonconductive minerals, bacterial biofilms, and self-assembled protein monolayers. The microscope incorporates temperature control, fluid cells, and an environmental chamber that collectively allow imaging of air- and moisture-sensitive samples under controlled conditions.

The microscope supports most AFM imaging techniques, including contact and intermittent-contact modes of operation. The intermittent-contact mode is magnetically driven (MAC™ mode). In addition, PicoSPM incorporates the capability to examine conductive materials by STM and by current-sensing AFM. The microscope can detect currents ranging from 1 pA to 100 nA and can perform I/V spectroscopy measurements in both STM and current-sensing AFM modes.

The microscope is equipped with Teflon fluid cells for in situ imaging in liquids. The cells can hold aqueous and nonaqueous media and have flow-through capabilities, allowing users to perform real-time kinetic experiments while imaging the samples. Coupled with the electrochemical unit that includes a low-noise potentiostat/galvanostat, fluid cells can be used for imaging under electrochemical control both in the AFM and in the STM modes of operation.

Two temperature-controlled sample mounts can heat and/or cool samples from -30°C to 250°C. Additionally, the microscope is equipped with an environmental chamber that can be used to maintain samples in a controlled atmosphere during imaging. This allows users to maintain complete control of the imaging environment, and creates the capability to perform in situ kinetic measurements on a variety of systems from minerals to biological systems.

User Portal Name: Microscope: Scanning Probe, STM/AFM, PicoSPM
Instrument ID:
1042
Availability: 10 hours a day, 5 days a week
Shewanella oneidensis MR-1 produced electrically conductive pilus-like appendages called bacterial nanowires in direct response to electron-acceptor...
    • Allows imaging of air and moisture-sensitive samples under controlled conditions
    • Capable of tetecting currents from 1pA to 100 nA
    • Can perform I/V spectroscopy in STM and current-sensing AFM modes
Posted: Wednesday, April 17, 2013 - 17:00
Scientists from EMSL and Pacific Northwest National Laboratory tracked carbon dioxide using EMSL’s scanning tunneling microscope. They found, in...