Facilities

Kelvin probe force microscopy (KPFM)

KPFM is also known as surface potential microscopy, is a noncontact variant of atomic force microscopy (AFM). With KPFM, the work function of surfaces can be observed at atomic or molecular scales.

X-Ray Diffraction (XRD)

X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions.

Time-Resolved Photoluminescence (TRPL)

Photoluminescence lifetime is an intrinsic characteristic of a luminescent character that provides insight into the species excited state dynamics. Time-Resolved Photoluminescence (TRPL) is a choice for studying the electronic processes that result in the emission of photons– a process called fluorescence.

External Quantum Efficiency (EQE)

EQE-R quantum efficiency system is a PV cell tester that can provide cell EQE. IPCE, IQE, and spectral response data accurately and rapidly. The figure on the right shows the EQE spectra and the corresponding integrated current densities of the SnO2 (an ETL layer) and modified PSCs.

Electrochemical impedance/ UV-vis spectrometers

EIS is a nondestructive electrical characterization method to investigate the charge dynamics in the bulk and/or interfaces of different perovskite materials with both electronic and ionic behaviors.

UV-Vis Spectroscopy (or Spectrophotometry) is a quantitative technique used to measure how much a sample absorbs light. This could be done by measuring the intensity of light that passes through a sample with respect to the intensity of light through a reference sample or blank.

Dual (DC/RF) magnetron sputtering sources

Sputtering relies on a physical process where any particles of interest are ejected from a solid target material; this is due to the bombardment of the target by energetic gases. We use the RF&DC sputtering system for preparation of different layers of metal and semiconducting as well as composite materials. The advanced energy MDX 1.5K and RFX 600 equipped with ATX matching network are used as DC and RF power sources, respectively. A rotating substrate holder is installed in the system for uniformity of the deposited films.

Ultrasonic sprayed coating

Ultrasonic spray nozzles are constructed to vibrate longitudinally at high frequency by means of piezoelectric transducers. Within a collaborative work with Dr. Supasai in nano-photovoltage laboratory (http://nano-pv.sci.ku.ac.th/), the chemical-sprayed nebulous system has been designed and setup for low-cost thin film preparation. The utilization of co-misted generators containing different chemical sources benefits to prepare materials in different stoichiometries.