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We demonstrate area-selective atomic layer deposition (ALD) of oxides on DNA nanostructures. Area-selective ALD of Al2O3, TiO2, and HfO2 was successfully achieved on both 2D and 3D DNA nanostructures deposited on a polystyrene (PS) substrate. The resulting DNA–inorganic hybrid structure was used as a hard mask to achieve deep etching of a Si wafer for antireflection applications. ALD is a widely used process in coating and thin film deposition; our work points to a way to pattern oxide materials using DNA templates and to enhance the chemical/physical stability of DNA nanostructures for applications in surface engineering.

Here, we report the synthesis and near‐infrared photoluminescence properties of small‐diameter (∼2–3 nm) silver and copper nanoparticles. Periodic trends in nanoparticle quantum yields, observed lifetimes, and emission peak features are studied and compared to each other as well as to previously reported small diameter gold nanoparticles. These trends are distinct from optoelectronic features observed from either their cluster (4–100 atoms) or larger NP (diameter >5 nm) counterparts. Taken together, the successful synthesis and characterization of these materials introduces potential alternatives to small, Au‐based nanoparticles in photoluminescence‐driven applications such as bio‐labeling and sensing, as well as provides additional insight into particle properties at this important size range between molecular and bulk materials.

It is commonly accepted that during conductive atomic force microscopy (CAFM) measurement in ambient, a liquid meniscus can form between the tip and the sample. Such a liquid bridge, normally assumed to be composed of water, is a major factor in analyzing and understanding CAFM results. Here, we show that the adsorption of adventitious hydrocarbons from the air to a surface can greatly affect CAFM data both in imaging mode and in local spectroscopy (current–voltage or I – V curves). We propose a model to explain the phenomena whereby hydrocarbon contaminates contribute to the composition of the liquid bridge between the tip and the sample.