This work reports laboratory angle resolved XRF measurements with the goal of establishing laboratory techniques to obtain a more complete idea of the intralayer composition of multilayer samples.

Angle‐resolved X‐ray fluorescence spectroscopy gives access to elemental analysis of nanoscaled materials. The two main techniques of this method are grazing incidence X‐ray fluorescence (GIXRF) and grazing emission X‐ray fluorescence (GEXRF) spectroscopy. Principles of both techniques including main applications are discussed in this Review. The main focus lies on the description of GEXRF technique and its new analytical possibilities in the nano‐world.

The development of thin-film thermoelectric applications in sensing and energy harvesting can benefit largely from suitable deposition methods for earth-abundant materials. In this study, p-type copper oxide thin films have been prepared on soda lime silicate glass by direct current (DC) magnetron sputtering at room temperature from a pure copper metallic target in an argon atmosphere, followed by subsequent annealing steps at 300 °C under various atmospheres, namely air (CuO:air), nitrogen (CuO:N) and oxygen (CuO:O). The resultant films have been studied to understand the influence of various annealing atmospheres on the structural, spectroscopic and thermoelectric properties. X-ray diffraction (XRD) patterns of the films showed reflexes that could be assigned to those of crystalline CuO with a thin mixed Cu^(I)Cu^(II) oxide, which was also observed by near edge X-ray absorption fine structure spectroscopy (NEXAFS). The positive Seebeck coefficient (S) reached values of up to 204 μV K⁻¹, confirming the p-type behavior of the films. Annealing under oxygen provided a significant improvement in the electrical conductivity up to 50 S m⁻¹, resulting in a power factor of 2 μW m⁻¹ K⁻². The results reveal the interplay between the intrinsic composition and the thermoelectric performance of mixed copper oxide thin films, which can be finely adjusted by simply varying the annealing atmosphere.

Fire‐gilding is a historic technique for the application of golden layers on a number of different base materials utilizing a gold amalgam. This technique leaves a significant amount of Hg in the golden layer, giving archeometrists a reliable indicator to identify fire‐gildings. Recent findings on presumably fire‐gilded objects have shown in several cases significantly lower Hg content than previously studied objects. This prompted a synchrotron‐based X‐ray fluorescence investigation into the Hg distribution along the material–gilding interface, as well as a series of measurements regarding the Hg content development in fire‐gilded samples during artificial aging. This work presents findings on laboratory‐prepared fire‐gildings, indicating an Hg enrichment at the interface of fire‐gilded silver samples. Notably, such an enrichment is missing in fire‐gilded copper samples. Further, it is confirmed that fire‐gilded layers typically do not undercut an Hg bulk content of 5%. In this light, it seems improbable that ancient samples that contain <5% Hg are fire‐gilded. The results presented in this study might lead to a non‐destructive method to identify the Hg enrichment at the interface. This might be obtained by a combination of different non‐destructive measurements and might also work unambiguously in samples in which the gold top layer is altered.

In principle, most X-ray sensitive pixelated detectors like CCDs or active pixel sensors (e.g. CMOS detectors) can be operated in single-photon counting (SPC) mode. In combination with rather simple data post-processing steps, this allows the exploitation of energy-dispersive properties similar to hybrid-pixel detectors and pnCCDs. For example, energy discrimination can be used to simultaneously measure the spatial distribution of various fluorescence lines on the detector chip or enable noise suppression in wavelength-dispersive measurements. Furthermore, due to the analysis of the charge distribution on the detector resulting from an absorbed X-ray photon, sub-pixel spatial resolution can be achieved. Where applicable, those additional features can be utilized without any hardware modification at the detector. There is a large potential for novel experiments and sensitivity gain in many laboratories already applying pixelated detectors, but only a few experiments indeed use this potential. The up until now published algorithms are hardly validated and rarely described in detail. Besides a thorough description of various algorithms for photon event evaluation, this work concentrates on a quantitative and qualitative comparison of such algorithms with respect to energy resolution, efficiency and photon recovery. For this purpose, the algorithms are tested on simulated data featuring various detector noise and charge-cloud size values and the influence of noise thresholds and photon density is discussed. Finally, we present two examples to demonstrate the advantages of photon event evaluation and highlight its benefits for X-ray spectroscopic applications.