Templated Synthesis of Diamond Nanopillar Arrays Using Porous Anodic Aluminium Oxide (AAO) Membranes

Abstract

Diamond nanostructures are mostly produced from bulk diamond (single- or polycrystalline) by using time-consuming and/or costly subtractive manufacturing methods. In this study, we report the bottom-up synthesis of ordered diamond nanopillar arrays by using porous anodic aluminium oxide (AAO). Commercial ultrathin AAO membranes were adopted as the growth template in a straightforward, three-step fabrication process involving chemical vapor deposition (CVD) and the transfer and removal of the alumina foils. Two types of AAO membranes with distinct nominal pore size were employed and transferred onto the nucleation side of CVD diamond sheets. Subsequently, diamond nanopillars were grown directly on these sheets. After removal of the AAO template by chemical etching, ordered arrays of submicron and nanoscale diamond pillars with ~325 nm and ~85 nm diameters were successfully released.

Advances in the Fabrication of Nanoporous Anodic Aluminum Oxide and Its Applications to Sensors: A Review

“…The barrier type of AAO, with a thin and compact structure, was largely used in the past for protection and dielectric capacitors [6]. By contrast, the porous type of AAO, with a highly ordered nanopore arrangement, has received increasing attention as a template for fabricating nanowires or synthesizing other 1D/2D nanostructures [6][7][8][9][10], and as a nanopattern transfer for micro/nano applications, for instance, in the triboelectric nanogenerator (TENG) field [11,12]. AAO, as a nanomaterial template, is fabricated using certain electrochemical processes.…”

“…Since the 1950s, thousands of AAO-related papers have been published in international journals, covering a wide range of applications. These include nanomaterial synthesis [7,[29][30][31][32], electrical humidity sensors [33][34][35][36][37][38][39][40][41][42][43][44][45][46], optical sensors [47][48][49][50][51][52][53], photonic and electronic devices [54][55][56][57][58][59][60][61][62][63][64], photocatalysis [65][66][67], bio-applications [68][69][70], and other fields [71][72][73], as highlighted in Figure 1. A noteworthy contribution to AAO-based nanomaterial synthesis is the work proposed by Masuda et al [74...…”