铜掺杂硫化锡负载氧化石墨烯气凝胶光催重整纤维素酶解液产乳酸的研究

Lactic acid production from copper-doped tin sulphide-loaded graphene oxide aerogel photocatalytic reforming of cellulose digest

本研究采用水热-冷冻干燥-煅烧的方法成功制备了铜掺杂硫化锡负载氧化石墨烯气凝胶(Cu x SnSO@GO),并采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和紫外-可见光反射分析(UV-vis DRS)对材料进行表征,研究了不同Cu掺杂量和不同反应时间对光催重整纤维素酶解液产乳酸的影响。结果表明,铜成功的掺入到SnS_(2)结构中,产生表面硫缺陷,改变了SnS_(2)的带隙,提高了SnS_(2)的光催属性。此外,煅烧工艺制备的Cu x SnSO@GO改善了光生电子和空穴的分离效率,显著提高了光催化效率。Cu x SnSO@GO在可见光照射下能够高效的光催重整纤维素酶解液产乳酸,当Cu掺杂量x=0.06反应时间为4 h时,Cu x SnSO@GO具有38.8%的最佳产率。Cu x SnSO@GO形成的表面硫空位、高吸收性、可调节的能带结构以及煅烧后形成的Cu x SnS_(2)-SnO 2异质结都有利于乳酸的选择性转化,这为研究生物质光催化重整的机理提供了一种新的途径。

In this study,copper doped tin sulfide supported graphene oxide aerogels were successfully prepared by hydrothermal freeze-drying calcination method(Cu x SnSO@GO).The material was characterized by XRD,SEM,TEM,and UV-vis DRS,and the effects of different Cu doping amounts and reaction times on the production of lactic acid from photocatalytic reforming of cellulose digest were studied.The results showed that copper was successfully incorporated into the SnS_(2) structure,resulting in surface sulfur defects,changing the band gap of SnS_(2),and improving its photocatalytic properties.In addition,Cu x SnSO@GO produced by the calcination process improved the separation efficiency of photo generated electrons and holes,significantly improving photocatalytic efficiency.Under visible light irradiation,Cu x SnSO@GO can efficiently photocatalytic reform the cellulose hydrolysis and lactic acid can be achieved.When the Cu doping amount is 6%,the reaction time is 4 hours,Cu x SnSO@GO has an optimal yield of 38.8%.The Cu x SnSO@GO surface sulfur vacancies formed,high absorption,adjustable band structure,and the Cu x SnS_(2)-SnO 2 heterojunction formed after calcination are all conducive to the selective conversion of lactic acid,providing a new approach for studying the mechanism of biomass photocatalytic reforming.