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The pervasive use of toxic nitroaromatics in industrial processes and their prevalence in industrial effluent has motivated the development of remediation strategies, among which is their catalytic reduction to the less toxic and synthetically useful aniline derivatives. While this area of research has a rich history with innumerable examples of active catalysts, the majority of systems rely on expensive precious metals and are submicron- or even a few-nanometer-sized colloidal particles. Such systems provide invaluable academic insight but are unsuitable for practical application. Herein, we report the fabrication of catalysts based on ultralow loading of the semiprecious metal ruthenium on 2–4 mm diameter spherical alumina monoliths. Ruthenium loading is achieved by atomic layer deposition (ALD) and catalytic activity is benchmarked using the ubiquitous para-nitrophenol, NaBH4 aqueous reduction protocol. Recyclability testing points to a very robust catalyst system with intrinsic ease of handling. 

This article reviews the process-structure-property relationship in doped ZnO thin films via atomic layer deposition (ALD). ALD is an important manufacturing-scalable, layer-by-layer, thin film deposition process that precisely controls dopant type and concentration at the nanoscale. ZnO is an important technological material, which can be doped to modulate structure and composition to tailor a wide variety of optical and electronic properties. ALD doped ZnO is viewed as a transparent conducting oxide for application in solar cells, flexible transparent electronics, and light-emitting diodes. To date, there are 22 elements that have been reported as dopants in ZnO via ALD. This article studies the underlying trends across dopants and establishes generalized relationships for (1) the role of ALD process parameters, (2) the impact of these parameters on the structure of the ZnO matrix, and (3) the impact of dopants on the optical and electrical properties. The article ends with a brief discussion on the limitations of the ALD-based doping scheme, knowledge gaps in the compositional maps, and a perspective on the future of ALD doped ZnO films. 

The intrinsic and doped amorphous silicon layers in silicon heterojunction solar cells parasitically absorb light in the short wavelength region of the solar spectrum, lowering the generation current available to the device. Herein, a promising alternative to the hole‐selective amorphous silicon contact layers using only wide bandgap, transparent oxide materials is presented. Using thermal atomic layer deposition, a 1 nm hydrogenated aluminum oxide layer is deposited followed by a 4 nm molybdenum oxide layer on n‐type crystalline silicon. This contact stack provides an effective carrier lifetime of 1.14 ms. It is shown that the molybdenum oxide layer is successfully deposited with a high work function, which facilitates efficient hole extraction and repels majority carriers from the c‐Si surface. Then the implied open‐circuit voltage, saturation current density, and contact resistivity are recorded as a function of contact annealing temperature and show that they are relatively stable up to 200 °C.