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At present, we are facing a severe energy and environment crisis. Solar energy conversion to hydrogen fuel or directly to electricity has been considered as a promising approach. Some methods based on the electron-hole pair generation in semiconductors have been studied since Fujishima et al in 1972. Now, a new structure based on Localized Surface Plasmon Resonance (LSPR) provides us another approach to harvest solar energy. Recently, Mubeen et al reported gold nanorod based plasmonic device for solar water splitting with titanium oxide layer and platinum nanoparticles as electron filter and hydrogen catalyst, respectively, which can harvest hot electrons arising from the decay of surface plasmons excited by the solar energy. Also, it is possible to harvest photons from the entire solar spectrum by modifying the geometry or the surface of the gold nanorods. However, the efficiency of this device is only 0.1%, which is low for practical use. Here we explore two methods to increase the efficiency. First, we modified the anodized aluminum oxide (AAO) template to increase the spacing of the nanorods to enlarge the total accessibility of the surface area and minimize potential effects of device corrosion. Secondly we increase the overall production of hydrogen by achieving greater coverage of platinum nanoparticles. As a result, we have enlarged the spacing to 200±nm, which is 5 times of previously reported result. In the future, we aim for more effective coverage with the catalyst once the surface area of the nanorods is more accessible.