Applications of an amorphous silicon-based area detector for high-resolution, high-sensitivity and fast time-resolved pair distribution function measurements

摘要

The application of a large-area (41 x 41 cm, 2048 x 2048 or 1024 x 1024 pixel) high-sensitivity (detective quantum efficiency > 65%) fast-readout ( up to 7.5 or 30 Hz) flat-panel detector based on an amorphous silicon array system to the collection of high-energy X-ray scattering data for quantitative pair distribution function (PDF) analysis is evaluated and discussed. Data were collected over a range of exposure times (0.13 s-7 min) for benchmark PDF samples: crystalline nickel metal and amorphous silica (SiO2). The high real-space resolution of the resultant PDFs (with Q(max) up to similar to 40 angstrom(-1)) and the high quality of fits to data [R-Ni(0.13s) = 10.5%, R-Ni(1.3s) = 6.3%] obtained in short measurement times indicate that this detector is well suited to studies of materials disorder. Further applications of the detector to locate weakly scattering H-2 molecules within the porous Prussian blue system, Mn-3(II)[Co-III(CN)(6)](2) (.) xH(2), and to follow the in situ reduction of (PtO2)-O-IV to Pt-0 at 30 Hz, confirm the high sensitivity of the detector and demonstrate a new potential for fast time-resolved studies.