Welcome to the Surface Science Center Laboratory (SSCL) at SJSU
The Surface Science Center Laboratory (SSCL) at San Jose State University focuses on the atomic and molecular structure of bulk and nanoscale surfaces. Surfaces play an outsized role in chemistry, physics, biology and engineering. For example, platinum catalyst in a catalytic converter in automobiles removes toxic emissions (nitrogen oxide, nitrogen dioxide and carbon monoxide) after combustion and decreases air pollution (Catalytic converter). Work on surface reactions by Gerhardt Ertl (Gerhard Ertl) and Gabor Somorjai (Gabor Somorjai) led to a Nobel prize and Wolf Prize in surface chemistry (2007 Nobel Laureate). In biology, the influenze virus infects bronchial epithelial cells in a process described as multi-valent interaction wherein hemagglutinin on the virus surface and sialic acid groups on the cell surface bind and virus endocytosis begins. Whitesides et al. review polyvalent interactions in this highly cited review. Whitesides Review Polyvalent Interactions
Surface Science Center researchers Grace Jean-pierre, Jocelyn Valenzuela and Cynthia Melendrez collect X-ray photoelectron spectroscopy (XPS) data at The Molecular Foundry at Lawrence Berkeley National Laboratory. Information on Imaging and Manipulation Facility at The Molecular Foundry can be found here: The Molecular Foundry
Surface Science Center researcher Andres Arreola (2015-2018) images high-pressure high-temperature nanodiamond with 5-20 nm thick SiO2 shells using a high resolution transmission electron microscope (HRTEM). The HRTEM is a JOEL 2100 F and is capable of TEM, STEM (scanning TEM), STEM-EDS (energy dispersive X-ray spectroscopy) and electron energy loss spectroscopy (EELS). The 2100F is housed in the Imaging and Manipulation of Nanostructures facility at The Molecular Foundry (JOEL 2100F).
SSCL Research Thrusts
In the Wolcott lab we have projects involving:
- High-pressure high-temperature nanodiamond surface chemistry with nitrogen vacancy centers for biosensing applications and cellular imaging
- Metal oxide photoelectrochemical cells for solar fuel production
- Semiconductor quantum dot photophyics investigations (PbSe and CdSe)
- Photovoltaic cells using PbI3 perovskite thin films
In the foreground is the ultra-high vacuum analysis chamber at beamline 8-2 at Stanford Synchrotron Radiation Lightsource (SSRL). SSRL is operated by Stanford University for the Department of Energy. X-ray absorption spectroscopy and X-ray photoelectron spectroscopy experiments are conducted by Wolcott lab members at beamline 8-2 and 10-1. SSRL website
Wolcott lab members Cynthia Melendrez, Anida Len and Polo Tran preparing for a X-ray absorption spectroscopy experiment at the Stanford Synchrotron Radiation Lightsource (SSRL) beamline 8-2. Beamline 8-2 allows for surface chemistry investigations of low-Z elements such as carbon, nitrogen and oxygen. The Wolcott lab uses XAS to examine nanoscale diamond which hosts the nitrogen vacancy center, an atomic defect capable of magnetic and electric field sensing.
From left to right: Henry Yang, Carlos Amaral, Prof Wolcott, Tony Nguyen and Ryan Robinson take a break to smile that data collection is underway at 8-2 at SSRL. In the background is the analysis chamber for 8-2 (left) and 10-1 (right) at SSRL. These two beamlines provide soft X-ray emission from 100-1300 eV and is well suited for core-level absorption spectroscopy of low-Z elements. Information on X-ray absorption can be found here: X-ray absorption near edge structureXAS