We describe a simple, inexpensive coating method to produce thin silica and titania films with surfactant templated, orthogonally tilted cylindrical nanopore arrays. These films can be deposited onto any substrate because orientation of the 2D hexagonally close packed (HCP) mesophases out of the plane of the film is directed by a chemically neutral sacrificial copolymer layer. Orientation of the HCP mesophases through the entire thickness of films cured in open air is achieved by limiting the coating thickness. This generalizes the coating method by making it possible to deposit oriented films on substrates of any curvature and size. We find a critical thickness between 70 and 100 nm, below which the triblock copolymer surfactant-templated HCP phase aligns completely out of the plane of glass and silicon wafer substrates. Above this thickness, the effect of the chemically neutral bottom layer does not propagate across the entire film, and alignment of the HCP mesophases parallel to the (nonpolar) air interface produces a mixed orientation.

We fabricated ordered bulk heterojunction photovoltaic (PV) cells using a perfluoropolyether (PFPE) elastomeric mold to control the donor−acceptor interfacial morphology within devices. Anatase titania nanostructures with postlike features ranging from 30 to 100 nm in height and 30 to 65 nm in spacing were fabricated using the Pattern Replication In Nonwetting Templates (PRINT) process. The nanostructured devices showed a 2-fold improvement in both short-circuit current (J sc) and power conversion efficiency (PCE) relative to reference bilayer cells. Additionally, the titania was functionalized with Z907 dye to increase both the short-circuit current (J sc) and open-circuit voltage (V oc). As a result we observed a device efficiency (ηeff) of 0.6%, the highest recorded efficiency value so far for an imprinted titania−P3HT device.