Themed collection Photoelectron spectroscopy and the future of surface analysis

Three different directions have evolved during the last decade and will become even more essential in the future to come and these are in situ and operando approaches, interface probing and ultrafast time resolved measurements.

Recent advances in photoelectron spectroscopy are reviewed, focussing on advances in in situ and time-resolved measurements, and in extending the sampling depth of the technique. The future prospects for each are considered.

Cryo-XPS study of fast-frozen particulate PbS and ZnS in aqueous solutions allows the minimizing of the distortions of the reaction interfaces.

Dynamic surface and subsurface morphology and chemistry of socketed nanoparticles is monitored in situ for an important emerging class of nanoparticles.

HAXPES enables the detection of buried interfaces with an increased photo electron sampling depth.

Graphene on Ir(111) was hydrogenated selectively in the HCP and FCC regions by controlling the substrate temperature during exposure. Hydrogenated carbon in these areas both form ordered clusters, but are found to contribute to different components.

The temperature-dependence of photoemission from a gold alloy, n-type β-Ga₂O₃ and p-type diamond reveals reversible and irreversible changes in energy, due to changes in surface chemistry, band-bending, thermal expansion and a surface photovoltage.

Time-resolved photoemission spectroscopy is used to study the photophysics of droplets containing dioctyl phthalate. Long-lived excited states survive longer at lower phthalate concentrations, and in larger or electrically charged droplets.

Pd and Pd–Pt alloys are studied with NAP-XPS under methane oxidation conditions. Pd–Pt catalysts showed greater resistance to oxidation under reaction conditions, with this coupled to surface restructuring and Pt migration away from the surface.

We have used the ΔSCF method for calculating TM 2p_3/2 core electron binding energies in compounds of first row transition metals. After correcting for element dependent systematic errors, the MAE of the calculated binding energies is just 0.20 eV.

The optical excitation of a 2H-MoTe₂ crystal leads to a lattice deformation in the out-of-plane direction which has a lifetime of about 600 ps. The atomic displacement results in a transient binding energy shift of the Te 4d core level.

We have monitored the temporal evolution of the band bending at controlled silicon surfaces after a fs laser pump excitation.

We demonstrate the validity of using valence resonant X-ray photoelectron spectroscopy to identify atomic contributions for both solutes and solvents.

Different operando approaches based in PES were used and compared under OER conditions on IrO_x. ResPES indicates that single coordinated oxygen atoms (μ₁-O) are the active species yielding the formation of peroxo (μ₁-OO) and finally O₂ as product.

We use ambient pressure X-ray photoelectron and absorption spectroscopies coupled with on-line gas detection to investigate in situ performance and interface chemistry of an electrodeposited Cu on a carbon support under conditions of CO₂ reduction.

We propose a strategy for time-resolved measurements that can provide quantitatively reconciled spectroscopic (AP-XPS) and kinetic (TAP) information about catalytic reactions on tailored 2D and 3D model materials prepared via Atomic layer deposition (ALD).

We present calculations of the photoelectron spectra of water and a simple solution of NaCl under pressure at conditions relevant to the Earth’s interior (11 GPa and 1000 K).

In situ deposition is critical to studying interfacial reactions between alkali-metals and solid electrolytes. The species formed on Li₆PS₅Cl are found to vary with deposition method, with impingement of more energetic atoms causes physical damage.

In this review, the status of hard X-ray photoelectron spectroscopy (HAXPES) implemented with chromium Kα excitation (5.414 keV) and applied to technological research in nanoelectronics is presented.

Methanol oxidation on amorphous aluminum-transition metal oxides: active sites, intermediates, and support effects via photoelectron spectroscopy and mass spectrometry.

In situ and time-resolved APXPS reveals the initial ALD process beyond the standard ligand exchange model, resulting in native oxide-free InAs/HfO₂ interfaces for high-speed MOSFET.

XPS data recorded under AC modulation together with simulations allows extraction of impedance-type information.

XPS spectra demonstrate that the chemistry of well-inhibited carbon steel interfaces, formed through sorption of organic surface-actives, is acid dependent.