TiO₂/MoX₂?X=S?Se?Heterostructure And Its Application For Catalytic Hydrogen Evolution

With the rapid development of human society,more and more fossil energy has been consumed,at the same time,the environment has brought a huge burden due to number of fossil energy consume.In order to sustainable develop the human society,exploit a new energy is definitely urgent.Hydrogen energy provided by gaseous hydrogen has been considered as the most promising candidate to supply clean energy in the future due to its rich raw materials,pollution-free and high energy density and other advantages.Catalytic hydrogen evolution is one of the most effective ways to obtain hydrogen energy.TiO₂,as the typical photocatalyst,have been investigated deeply because of its low-cost,high chemical stability and other advantages,but the board band-gap and high electron-hole pair recombination rate limited its widely application on photocatalytic hydrogen evolution.In electrocatalytic hydrogen evolution,the effective catalyst such as metal platinum can't be used on large scale because of high-cost,rare resources and other deficiencies.With the emergence of novel two-dimensional materials,it has been widely investigated in hydrogen evolution field due to its excellent electronic properties,optical properties and so on,in this paper,we have make some improvements to enhance its catalytic hydrogen evolution ability of TiO₂ and MoSe2 or MoS₂,the details as follows:1.Because of the high recombination rate of electon-hole pairs and limited range of solar absorption of TiO₂ photocatalyst materials,we introduced a two-dimensional material MoSe2 with a narrow bandgap,to combine with TiO₂ form a tpye ?TiO₂/MoSe2 heterostructure,this heterostructure promote the separation of photogenerated electron-hole pairs and broaden the range of light absorption,thereby improving the efficiency of photocatalytic hydrogen evolution.2.Investigation demonstrated that the active sites restricted on the thermodynamically unstable area of the layered MoS₂ nanosheets for hydrogen evolution.We fabricated a MoS₂/TiO₂ composite that TiO₂ nanoparticles loading on MoS₂ nanosheets,additional active sites could be formed in the interface of MoS₂/Ti O2 composite,lead to the improvement of active sites density thereby enhanced the catalytic efficiency.