The problem is instability of oxide. The problem was overcome by usind atomic layered deposition (ALD) technique that involves covering semi conductor with thin film of atoms as zinc oxide and titanium oxide. Cuprous oxide is inexpensive and widely available, this ALD technique give complete impermeable layer. The process advances photo-electrochemical production of Hydrogen
Dr.Grimes (2005) writes at Penn state, Research work is under way to harness solar energy through highly ordered arrays of titania nanotubes arrays that would produce hydrogen and ultimately lead to rise in solar efficiency. It’s about exposing water with these arrays to sunlight, through the process of photolysis and UV illumination efficiency would be high almost 13% and result in more hydrogen against per photon. The purpose is to replace most used and depleting energy sources as petroleum through creating replenish-able stock of alternative energy.
At University of Utah (2007) physicists worked to convert heat into sound and then sound into electricity through formulating new devices. First they developed new heat engines formerly called thermoacoustics prime movers and then transformed sound into power using piezoelectric (piezo for pressure). How it works? These devices are addressed in resonators (cylinder shaped), that contains pile of material and kept in between hot and cold heat exchanger. After heat is applied, it builds to threshold with air producing sound at single frequency, these waves squeeze the device and electrical voltage is produced. These devices require flexibility of moving parts but they have long life.
Wood Angela(2008) studied that Photovoltaic or solar panels are most known these days due to least operational cost. It use silicon or any other similar material for chemical reaction with light; results in flow of currents that can be used or stored in battery. Solar Power generation could be enhanced