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We review a method to produce cylindrical magnetic nanowires displaying several segments, with a large versatility in terms of segment diameter and length. It is based on electroplating in alumina templates, the latter being prepared by several steps of anodization, wet etching, and atomic layer deposition to produce, widen, or shrink pores, respectively. We propose an analytical model to analyze the in-plane and out-of-plane magnetization loops of dense assemblies of multisegmented wires. The model considers inter-wires dipolar fields and end-domain curling and predicts the switching field of individual wires with no adjustable parameter. Its ingredients are crucial to extract reliable parameters from the fitting of loops, such as magnetization or the porosity of the array. [ABSTRACT FROM AUTHOR]

Disproportionation reactions of chlorosilane compounds in the presence of boron trichloride yield the compound H[B(SiCl3)4]. Spectroscopic analyses of the yellow‐whitish solid with IR‐, Raman‐, and NMR‐spectroscopy (29Si, 11B) show the presence of a highly symmetric anion containing boron, which is fourfold coordinated with silicon. Due to the high symmetry 1J(11B,29Si) and even 1J (10B, 29Si) couplings can be observed in the NMR spectra of the dissolved compound. The crystal structure analysis with a crystal obtained from toluene solution proves the existence of a highly symmetric borate anion, which is stabilized by four trichlorosilyl groups. The molecular structure consists of a para‐protonated toluene cation and the weakly coordinating borate anion [B(SiCl3)4]−. Quantum chemical analysis of the tetrakis(trichlorosilyl)borate ion shows a negatively charged boron atom and the presence of polar Si−Cl and Si−B bonds. Highly reactive compounds [E(SiCl3)n]− which are stabilized solely by trichlorosilyl groups have been prepared with E=C, Si, Ge, P, S in recent years. The superacid H[B(SiCl3)4] represents a new member in this elusive compound family. [ABSTRACT FROM AUTHOR]

Disproportionation reactions of chlorosilane compounds in the presence of boron trichloride yield the compound H[B(SiCl3)4]. Spectroscopic analyses of the yellow‐whitish solid with IR‐, Raman‐, and NMR‐spectroscopy (29Si, 11B) show the presence of a highly symmetric anion containing boron, which is fourfold coordinated with silicon. Due to the high symmetry 1J(11B,29Si) and even 1J (10B, 29Si) couplings can be observed in the NMR spectra of the dissolved compound. The crystal structure analysis with a crystal obtained from toluene solution proves the existence of a highly symmetric borate anion, which is stabilized by four trichlorosilyl groups. The molecular structure consists of a para‐protonated toluene cation and the weakly coordinating borate anion [B(SiCl3)4]−. Quantum chemical analysis of the tetrakis(trichlorosilyl)borate ion shows a negatively charged boron atom and the presence of polar Si−Cl and Si−B bonds. Highly reactive compounds [E(SiCl3)n]− which are stabilized solely by trichlorosilyl groups have been prepared with E=C, Si, Ge, P, S in recent years. The superacid H[B(SiCl3)4] represents a new member in this elusive compound family. [ABSTRACT FROM AUTHOR]

Amorphous MoS 2 has been investigated abundantly as a catalyst for hydrogen evolution. Not only its performance but also its chemical stability in acidic conditions have been reported widely. However, its adhesion has not been studied systematically in the electrochemical context. The use of MoS 2 as a lubricant is not auspicious for this purpose. In this work, we start with a macroporous anodic alumina template as a model support, add an underlayer of SnO 2 to provide electrical conduction and adhesion, then provide the catalytically active, amorphous MoS 2 material by atomic layer deposition (ALD). The composition, morphology, and crystalline or amorphous character of all layers are confirmed by spectroscopic ellipsometry, X-ray photoelectron spectroscopy, grazing incidence X-ray diffractometry, scanning electron microscopy and energy dispersive X-ray spectroscopy. The electrocatalytic water reduction performance of the macroporous AAO/SnO 2 /MoS 2 electrodes, quantified by voltammetry, steady-state chronoamperometry and electrochemical impedance spectroscopy, is improved by annealing the SnO 2 layer prior to MoS 2 deposition. Varying the geometric parameters of the electrode composite yields an optimized performance of 10 mA cm -2 at 0.22 V overpotential, with a catalyst loading of 0.16 mg cm -2 . The electrode's stability is contingent on SnO 2 crystallinity. Amorphous SnO 2 allows for a gradual dewetting of the originally continuous MoS 2 layer over wide areas. In stark contrast to this, crystalline SnO 2 maintains the continuity of MoS 2 until at least 0.3 V overpotential., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

TiO 2 nanotubes generated by anodization of metallic titanium sputter-coated on indium tin oxide (ITO) substrates are used as a conductive scaffold for all solid-state Sb 2 S 3 -sensitized extremely thin absorber (ETA) solar cells. A blocking layer of TiO 2 placed between Ti and ITO in combination with optimized Ti deposition and anodization conditions enables the formation of crack-free layers of straight, cylindrical TiO 2 nanotubes of tunable length and diameter. ALD (atomic layer deposition) is subsequently used to coat this substrate conformally with a highly pure Sb 2 S 3 light absorber layer under an inert atmosphere. The high absorption coefficient of Sb 2 S 3 as compared to molecular dyes allows for the utilization of very short nanotubes, which facilitates the infiltration of the organic hole transport material and formation of a p-i-n heterojunction in an interdigitated and tunable geometry. We investigate the influence of nanotube length and of the absorber thickness to enhance the photocurrent value to twice that of planar reference structures., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)