High‐Throughput Screening of Thin‐Film Semiconductor Material Libraries I: System Development and Case Study for TiWO

Abstract

An automated optical scanning droplet cell (OSDC) enables high-throughput quantitative characterization of thin-film semiconductor material libraries. Photoelectrochemical data on small selected measurement areas are recorded including intensity-dependent photopotentials and -currents, potentiodynamic and potentiostatic photocurrents, as well as photocurrent (action) spectra. The OSDC contains integrated counter and double-junction reference electrodes and is fixed on a precise positioning system. A Xe lamp with a monochromator is coupled to the cell through a thin poly(methyl methacrylate) (PMMA) optical fiber. A specifically designed polytetrafluoroethylene (PTFE) capillary tip is pressed on the sample surface and defines through its diameter the homogeneously illuminated measurement area. The overall and wavelength-resolved irradiation intensities and the cell surface area are precisely determined and calibrated. System development and its performance are demonstrated by means of screening of a TiWO thin film.

Tuning Light‐Driven Water Oxidation Efficiency of Molybdenum‐Doped BiVO4 by Means of Multicomposite Catalysts Containing Nickel, Iron, and Chromium Oxides

“…Supporting electrolyte was 0.1 M sodium tetraborate, pH 9.3. The prepared samples were examined with the use of an optical scanning droplet cell (OSDC) . The dimensions of the working electrode were determined by the diameter of the cell tip opening (0.735±0.037 mm 2 ).…”

High‐Throughput Screening of Thin‐Film Semiconductor Material Libraries II: Characterization of FeWO Libraries

“…To screen for interesting materials, an in-house-developed, fully automated optical scanning droplet cell (OSDC) setupw as used, which is described elsewhere. [18] XRD mapping revealed the existence of three different crystalline phases and an amorphous region in the investigated FeÀ WÀOc ompositionr ange. These regionss how also at hickness dependence, which is not unusualfor sputtered thin films.…”

“…Measurement of the photoelectrochemical (PEC) properties was carried out using ac ustom-designed automated OSDC. [18] The measurements were performed in at hree-electrode configuration using aP tw ire as counter electrode and aA g/AgCl 3 m KCl reference electrode. The selected measurement area was connected as working electrode.…”

Correlating Oxygen Evolution Catalysts Activity and Electronic Structure by a High-Throughput Investigation of Ni1-y-zFeyCrzOx

“…The SDC contained a double junction reference electrode (Ag/AgCl/3M KCl/0.1M KOH) with a potential of +239 mV vs. the normal hydrogen electrode (NHE) and a Pt-wire counter electrode housed in a special PTFE tip that was mounted on a three-axes micropositioning system32. Prior to the electrochemical measurements an electrochemical impedance spectrum (EIS) was acquired.…”