Xu Zhenbo, Sun Xiaolei, Chen Yao
The State Key Laboratory of Refractories and Metallurgy, Faculty of Materials, Wuhan University of Science and Technology, Wuhan 430081, China.
School of Materials Science and Engineering, Nankai University, Tianjin 300350, China.
Molecules. 2024 Apr 12;29(8):1761. doi: 10.3390/molecules29081761.
Graphene is a good support for immobilizing catalysts, due to its large theoretical specific surface area and high electric conductivity. Solid chemical converted graphene, in a form with multiple layers, decreases the practical specific surface area. Building pores in graphene can increase specific surface area and provide anchor sites for catalysts. In this study, we have prepared porous graphene (PG) via the process of equilibrium precipitation followed by carbothermal reduction of ZnO. During the equilibrium precipitation process, hydrolyzed N,N-dimethylformamide sluggishly generates hydroxyl groups which transform Zn into amorphous ZnO nanodots anchored on reduced graphene oxide. After carbothermal reduction of zinc oxide, micropores are formed in PG. When the Zn feeding amount is 0.12 mmol, the average size of the Pt nanoparticles on PG in the catalyst is 7.25 nm. The resulting Pt/PG exhibited the highest turnover frequency of 511.6 min for ammonia borane hydrolysis, which is 2.43 times that for Pt on graphene without the addition of Zn. Therefore, PG treated via equilibrium precipitation and subsequent carbothermal reduction can serve as an effective support for the catalytic hydrolysis of ammonia borane.
由于石墨烯具有较大的理论比表面积和高电导率，因此它是固定催化剂的良好载体。固体化学转化的多层石墨烯会降低实际比表面积。在石墨烯中构建孔隙可以增加比表面积并为催化剂提供锚固位点。在本研究中，我们通过平衡沉淀过程，随后对氧化锌进行碳热还原，制备了多孔石墨烯（PG）。在平衡沉淀过程中，水解的N，N-二甲基甲酰胺缓慢产生羟基，这些羟基将锌转化为锚定在还原氧化石墨烯上的无定形氧化锌纳米点。氧化锌经过碳热还原后，PG中形成了微孔。当锌的进料量为0.12 mmol时，催化剂中PG上铂纳米颗粒的平均尺寸为7.25 nm。所得的Pt/PG对氨硼烷水解表现出最高的周转频率，为511.6 min⁻¹，是未添加锌的石墨烯上铂的周转频率的2.43倍。因此，通过平衡沉淀和随后的碳热还原处理的PG可以作为氨硼烷催化水解的有效载体。
