Laser Synthesis Of Transition Metal Compounds Abundant With Structural Defects And Their Application In Energy Field

Vacanceis involved in materials will result in differences in physics and chemical properties,which show different properties compared with bulk.Vacancies are employed in nanomateirlas to enhance the performance of light absoprtion,electrocatalysis,and water evaporation.1.The mechanism of sulfur vacancies formation by laser ablation was studied.Furthur study show the vacancies were formed by reduction atmoesphere when laser ablation in reduction solvent.Meanwhile,organic salt as precusor to form large amount of Cu_1.4S nanoparticles with fine distribution.Different from other Cux S nanomaterials,this Cu_1.4S nanoparticles with month stability.This method was demonstrated as a new method to induce vacancies in materials.2.The mechanism of oxygen vacancies formation and performance enhancing were demonstrated.Compared with raw Co₃O₄,current density of laser products Co₃O₄ has increased 25-fold.Furthur study show the existance of oxygen vacancies facilitate the OH^-absorbed on surface,enhance the conductivity of catalysts.The oxygen vacancies were induced via non-equilibrium process.Hence this method was demonstrated as a new mathod to enhance the OER performance.3.Co possess good catalysis performance for OER.The catalytic activity mechanism of Co valance center was demonstrated.β-CoOOH nanosheets were synthesized by laser ablation show better catalytic performance compared with Co（II）centered Co（OH）₂ nanosheets.Compared with commercial RuO₂ and L-Co₃O₄nanoparticles,possess higher catalytic performance.The mechanism of CoOOH nanosheets formation was related to OH^-concentration.Higher concentration of OH^-was good for nanosheets formation.This facile and clean method syntheized clean catalysts without surface ligand was good for OER.4.Limited from broad band gap,the absorption of TiO₂ in visible light region is restricted.Involving in oxygen vacancies in TiO₂ benefit for enhancing light absoption.Non-equilibrium process by laser ablation induce large amount of oxygen vacancies in TiO₂.These defect TiO₂ nanoparticles possess high absorption at visible light region,which obtain 145%water evaporation frequency.5.The electrocatalytic sites of MoS₂ in hydrogen evolution reaction were at edge sites,which were difficult to expose.Laser induced larger amount of active sites,which come from Mo edge sites by laser ablation MoS₂ in alcohol.The catalytic performance was optimized.In-situ Raman spectra demonstrate the laser induced more edge,increase the HER performance.