Promoting the Direct H2O2 Generation Catalysis by Using Hollow Pd-Sn Intermetallic Nanoparticles

Although direct hydrogen (H-2) oxidation to hydrogen peroxide (H2O2) is considered as a promising strategy for direct H2O2 synthesis, the desirable conversion efficiency remains formidable challenge. Herein, highly active and selective direct H-2 oxidation to H2O2 is achieved by using hollow Pd-Sn inter-metallic nanoparticles (NPs) as the catalysts. By tuning the catalytic solvents and catalyst supports, the efficiency of direct H-2 oxidation to H2O2 can be optimized well with the hollow Pd2Sn NPs/P25 exhibiting H2O2 selectivity up to 80.7% and productivity of 60.8 mol kg(cat)(-1) h(-1). In situ diffuse reflectance infrared Fourier transform spectroscopy of CO adsorption results confirm the different surface atom arrangements between solid and hollow Pd-Sn NPs. X-ray photoelectron spectra results show that the higher efficiency of Pd2Sn NPs/P25 is due to its higher content of metallic Pd and higher ratio of Snx+, which benefit H2O2 production and selectivity.