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A hetero-nanostructured photoanode with enhanced near-infrared light harvesting is developed for photoelectrochemical cells by Alfred Iing Yoong Tok, Xiaogang Liu and co-workers on page 1603. The photoanode comprises upconversion nanoparticles on the surface of titanium oxide inverse opal. A nanoshell of titanium oxide is deposited on the nanoparticles, followed by CdSe quantum dots. Upon near infrared excitation, upconversion nanoparticles emit visible light that excites quantum dots for charge separation. Electrons are injected into titanium oxide with minimal carrier losses. This heteronanostructure is envisioned to be applicable to thin film, liquid-junction, and organic solar cells where near-infrared light can be harvested for improved photon-to-electricity conversion efficiency.