Atomic Layer Deposition of Platinum Catalysts on Nanowire Surfaces for Photoelectrochemical Water Reduction
journal contributionposted on 04.09.2013 by Neil P. Dasgupta, Chong Liu, Sean Andrews, Fritz B. Prinz, Peidong Yang
Any type of content formally published in an academic journal, usually following a peer-review process.
The photocathodic hydrogen evolution reaction (HER) from p-type Si nanowire (NW) arrays was evaluated using platinum deposited by atomic layer deposition (ALD) as a HER cocatalyst. ALD of Pt on the NW surface led to a highly conformal coating of nanoparticles with sizes ranging from 0.5 to 3 nm, allowing for precise control of the Pt loading in deep submonolayer quantities. The catalytic performance was measured using as little as 1 cycle of Pt ALD, which corresponded to a surface mass loading of ∼10 ng/cm2. The quantitative exploration of the lower limits of Pt cocatalyst loading reported here, and its application to high-surface-area NW photoelectrodes, establish a general approach for minimizing the cost of precious-metal cocatalysts for efficient and affordable solar-to-fuel applications.