Scalable neutral H2O2 electrosynthesis by platinum diphosphide nanocrystals by regulating oxygen reduction reaction pathways

Hui Li; Peng Wen; Dominique S Itanze; Zachary D Hood; Shiba Adhikari; Chang Lu; Xiao Ma; Chaochao Dun; Lin Jiang; David L Carroll; Yejun Qiu; Scott M Geyer

doi:10.1038/s41467-020-17584-9

Scalable neutral H₂O₂ electrosynthesis by platinum diphosphide nanocrystals by regulating oxygen reduction reaction pathways

Nat Commun. 2020 Aug 6;11(1):3928. doi: 10.1038/s41467-020-17584-9.

Authors

Hui Li^#¹, Peng Wen^#², Dominique S Itanze¹, Zachary D Hood^{3

4}, Shiba Adhikari⁵, Chang Lu¹, Xiao Ma¹, Chaochao Dun⁶, Lin Jiang⁷, David L Carroll⁶, Yejun Qiu⁸, Scott M Geyer⁹

Affiliations

¹ Department of Chemistry, Wake Forest University, Winston-Salem, NC, 27106, USA.
² Shenzhen Engineering Lab of Flexible Transparent Conductive Films, School of Materials Science and Engineering, Harbin Institute of Technology, Shenzhen, 518055, China.
³ Center for Nanophase Materials Sciences (CNMS), Oak Ridge National Laboratory (ORNL), Oak Ridge, TN, 37831, USA.
⁴ Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
⁵ Material Science and Technology Division (MSTD), Oak Ridge National Laboratory (ORNL), Oak Ridge, TN, 37831, USA.
⁶ Center for Nanotechnology and Molecular Materials, Department of Physics, Wake Forest University, Winston-Salem, NC, 27109, USA.
⁷ Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, China.
⁸ Shenzhen Engineering Lab of Flexible Transparent Conductive Films, School of Materials Science and Engineering, Harbin Institute of Technology, Shenzhen, 518055, China. yejunqiu@hit.edu.cn.
⁹ Department of Chemistry, Wake Forest University, Winston-Salem, NC, 27106, USA. geyersm@wfu.edu.

^# Contributed equally.

Abstract

Despite progress in small scale electrocatalytic production of hydrogen peroxide (H₂O₂) using a rotating ring-disk electrode, further work is needed to develop a non-toxic, selective, and stable O₂-to-H₂O₂ electrocatalyst for realizing continuous on-site production of neutral hydrogen peroxide. We report ultrasmall and monodisperse colloidal PtP₂ nanocrystals that achieve H₂O₂ production at near zero-overpotential with near unity H₂O₂ selectivity at 0.27 V vs. RHE. Density functional theory calculations indicate that P promotes hydrogenation of OOH* to H₂O₂ by weakening the Pt-OOH* bond and suppressing the dissociative OOH* to O* pathway. Atomic layer deposition of Al₂O₃ prevents NC aggregation and enables application in a polymer electrolyte membrane fuel cell (PEMFC) with a maximum r(H₂O₂) of 2.26 mmol h^-1 cm^-2 and a current efficiency of 78.8% even at a high current density of 150 mA cm^-2. Catalyst stability enables an accumulated neutral H₂O₂ concentration in 600 mL of 3.0 wt% (pH = 6.6).