The Prepration And Photocatalytic Performance Of Novel Bi₂MoO₆-based Hybrid Photocatalyst

Over the past few years,TiO2 has been widely used and investigated for the photodegradation of organic pollutants in water owing to its cheapness,strong oxidizing power and nontoxicity.However,due to its large band gap(3.2 eV for anataseTiO2),pure TiO2 can only absorb a small fraction of solar energy.Therefore,in order to effectively utilize solar energy in photocatalytic processes,some visible-light-driven photocatalysts have received great interest.Bi2Mo06 is an important Aurivillius oxide,and it is showed that Bi2MoO6 also possesses excellent visible-light-driven photocatalytic activity for water splitting and degradation of organic contaminants.But,there is still more than 55%of solar energy cannot be absorbed by Bi2MoO6.In order to further meet the requirement of environmental pollutants treatment,a great deal of effort has been made to develop Bi2MoO6 photocatalysts.Herein,for the first time.ordered mesoporous Bi2MoO6 crystals was synthesized employing a novel vacuum-assisted nanocasting method.More interestingly,this nanocasting method creatively utilized the amorphous complex as precursor instead of metal salt ions,by which a new kind of single phase Bi2MoO6(M-Bi2MoO6)could be successfully prepared.The as-prepared M-Bi2MoO6 exhibited much enhanced photocatalytic activity,which is about 5 times higher than that of conventional Bi2MoO6.More importantly,in this paper,through some quantitative results,the mechanism of the photocatalytic activity enhancement of ordered mesoporous Bi2MoO6 was thoroughly investigated.Using a simple one-step method,the Bi2MoO6-based photocatalyst with novel ultrathin nanohollow structure and simultaneous sub-10-nm Bi nanoparticles and sub-l-nm graphitic nitrogen-doped carbon nanodots(NCDs)modification were successfully obtained.The coordination impact between novel structure,SPR effect of Bi nanoparticles,up-conversion performance of graphitic NCDs and cooperative electronic capture property of Bi metal and NCDs make the hybrid simultaneously exhibits fast charge separation and broad spectrum photocatalytic activity under UV,Visible and Near-Infrared irradiation,leading to excellent photooxidation and photoreduction performance.Utilizing the chemical oxidation strategy,the graphene nanodots with uniform size were successfully synthesized.Then,the as-prepared graphene nanodots were incorporated into the mesoporous Bi2MoO6 framwork via electrostaticself-assembly.The novel photosensitization and peroxidase-like peoperties simultaneously promote photocatalytic performane enhancementof the as-prepared Bi2MoO6 based hybrid photocatalyst.Using anovel electrochemical tailoring method,the high-quality graphene nanodots were successfully synthesized.Moreover,utilizing the synergistic effect between the abundant surface oxygen defects over TiO2 catalyst and the anchored graphene nanodots,the hybrid Bi2MoO6 photocatalyst exhibits very excellent photocatalytic activity towards VOCs decomposition.The mesoporous Bi2MoO6 hollow photocatalyst which possesses novel core-shell structure and abundant surface oxygen defects was successfully synthesized via solvothermalroute follow by hydrogenationtreatment.The as-prepared Bi2MoO6 photocatalyst excellent catalysis activity towards sunlight-driven nitrogen fixation.At last,the mesoporous hollow Bi2MoO6 photocatalyst with ultrathin subunitswas originally synthesized via one-step solvothermal mothed.Benefiting from its excellent photoelectric conversion efficiency and abundant surface active sites,the as-prepared sample exhibits excellent photocatalytic performance for water oxidation.