By acetylene pyrolysis at 650 and 5508C, carbon nanotubes were synthesized successfully in porous alumina templates anodized in sulfuric and/or oxalic acid solution. For templates anodized in oxalic acid followed by boiling in distilled water, thermal decomposition of acetylene at 6508C in the pores results in the formation of carbon nanofibres. For templates anodized in sulfuric acid, only car...

Aluminum (Al) anodization leads to formation of porous structures with a broad spectrum of applications. Naturally or intentionally created defects on Al surfaces can greatly affect pore initiation. However, there is still a lack of systematic understanding on the defect dependent morphology evolution. In this paper, anodization processes on unpolished, polished, and nanoimprinted Al substrates...

Amorphous Si nanowires have been directly synthesized by a thermal processing of Si substrates. This method involves the deposition of an anodic aluminum oxide mask on a crystalline Si (100) substrate. Fe, Au, and Pt thin films with thicknesses of ca. 30 nm deposited on the anodic aluminum oxide-Si substrates have been used as catalysts. During the thermal treatment of the samples, thin films o...

We report on Si nanopatterning through an on-chip self-assembled porous anodic alumina (PAA) masking layer using reactive ion etching based on fluorine chemistry. Three different gases/gas mixtures were investigated: pure SF6, SF6/O2, and SF6/CHF3. For the first time, a systematic investigation of the etch rate and process anisotropy was performed. It was found that in all cases, the etch rate ...

Self-organized porous anodic alumina (PAA) formed by electrochemical anodization have become a fundamental tool to develop various functional nanomaterials. However, it is still a great challenge to break the interpore distance (Dint) limit (500 nm) by using current anodization technologies of mild anodization (MA) and hard anodization (HA). Here, we reported a new anodization mode named "Janus...

A surface with a simple nanopillar array and hierarchical micro-/nano structures consisting of microconvexes were fabricated by nanoimprinting using two types anodic porous alumina mold. On both surfaces, the height polymer nanopillars could be controlled adjusting anodization time for preparation Regarding water-repellent properties, higher contact angle was observed on structure than array. I...

Oxide-supported amine materials are widely known to be effective CO2 sorbents under simulated flue-gas and direct-air-capture conditions. Most work has focused on amine species loaded onto porous silica supports, though potential stability advantages may be offered through the use of porous alumina supports. Unlike silica materials, which are comparably inert, porous alumina materials can be tu...

A zeolite NaA (A-type zeolite of ca. 0.4 nm pore size; Linde Type A, LTA) membrane for the dehydration of alcohol was characterized by X-ray diffraction analysis (XRD). Also, the relationship between the X-ray absorption and the EtOH/H2O pervaporation (PV) dehydration performance (water selectivity and permeation flux) of the LTA membrane was first investigated. The LTA membranes used here were...