Picosecond time-resolved x-ray photoemission spectroscopy provides real-time electron distributions of donors and acceptors in a prototypical bipyridyl-ZnO hybrid light harvesting system. The measurements show that photo-injected electrons remain localized within the defect-rich surface region of the nanoporous ZnO substrate, revealing a challenge for the extraction of free charge carriers. Read more »
When Timing Isn’t Everything: Spontaneous Chemical Dynamics
Researchers combined aspects of x-ray photoelectron spectroscopy (XPS) with correlation spectroscopy—a statistical method capable of detecting patterns in microscopic fluctuations across space and time. The new technique, called time-correlation XPS, allows researchers to monitor dynamics without the need for a timed trigger. Read more »
Scientists Capture Candid Snapshots of Electrons Harvesting Light at the Atomic Scale
A team of scientists has gained important new insight into electrons’ role in the harvesting of light in gold/TiO2 nanoparticle photoelectrochemical (PEC) systems. The scientists say that their study can help researchers develop more efficient material combinations for the design of high-performance solar fuels devices. Read more »
A Probe of Light-Harvesting Efficiency at the Nanoscale
Using time-resolved experiments at the ALS, researchers found a way to count electrons moving back and forth across a model interface for photoelectrochemical cells. The findings provide real-time, nanoscale insight into the efficiency of nanomaterial catalysts that help turn sunlight and water into fuel through artificial photosynthesis. Read more »
Signal Speed in Nanomagnetic Logic Chains
A time-resolved x-ray imaging technique directly observes signal propagation dynamics in nanomagnetic logic (NML) chains. The technique can assess NML reliability on fast time scales and help optimize chain engineering for this promising ultralow-power computing architecture. Read more »