The utility of unmanned micro underwater vehicles (MUVs) is paramount for exploring confined spaces, but their spatial agility is often impaired when maneuvers require burst-propulsion. Herein we develop highaspect ratio (150:1), multiwalled carbon nanotube microarray membranes (CNT-MMs) for propulsive, MUV thrust generation by the decomposition of hydrogen peroxide (H 2 O 2 ). The CNT-MMs are grown via chemical vapor deposition with diamond shaped pores (nominal diagonal dimensions of 4.5 × 9.0 μm) and subsequently decorated with urchin-like, platinum (Pt) nanoparticles via a facile, electroless, chemical deposition process. The Pt-CNT-MMs display robust, high catalytic ability with an effective activation energy of 26.96 kJ mol -1 capable of producing a thrust of 0.209 ± 0.049 N from 50% [w/w] H 2 O 2 decomposition within a compact reaction chamber of eight Pt-CNT-MMs in series. A n upward trend in the research and use of unmanned underwater vehicles (UUVs), and in particular micro underwater vehicles (MUVs, small UUVS between 1 and 50 cm in length), for exploration of confined spaces such as ship wrecks, submerged oil pipelines, and various military purposes has been observed over recent years. 1À3 The locomotion of these vehicles is typically controlled by propellerbased systems, which are often used for long-endurance missions. 4À6 However, propeller-based systems are usually limited in their ability to perform tight radius turns, burst-driven docking maneuvers, and lowspeed course corrections. ABSTRACT The utility of unmanned micro underwater vehicles (MUVs) is paramount for exploring confined spaces, but their spatial