Catalyst Design for Electrochemical Oxygen Reduction toward Hydrogen Peroxide

Abstract

Precise electrochemical synthesis under ambient conditions has provided emerging opportunities for renewable energy utilization. Among many promising systems, the production of hydrogen peroxide (H2O2) from the cathodic oxygen reduction reaction (ORR) has attracted considerable interest in past decades due to the increasing market demands and the vital role of ORR in the electrocatalysis field. This work describes recent advances in cathodic materials for H2O2 synthesis from 2e- ORR. By using Pt as a stereotype, the tuning knobs are overviewed, including the intrinsic binding strength of oxygenated species, the intermediate diffusion path and the isolation of Pt–Pt ensembles that enable 2e- ORR pathway from 4e- total reduction. This knowledge is successfully applied to other transition metal systems and leads to the discovery of more efficient alloy catalysts with balanced improvement on both activity and selectivity. In addition, mesostructure engineering and heteroatoms doping strategies on carbon‐based materials, which significantly boost the H2O2 production efficiency as compared to intact carbon sites, are also reviewed. Finally, future directions and challenges of transferring developed catalysts from lab scale tests to pilot plant operations are briefly outlooked.

Chemical Identification of Catalytically Active Sites on Oxygen‐doped Carbon Nanosheet to Decipher the High Activity for Electro‐synthesis Hydrogen Peroxide

“…[6][7][8][9][10][11] In recent years,e normous efforts have been devoted to searching for cost-effective and high-performance electrocatalysts to produce H 2 O 2 . [12][13][14][15][16][17] Noble-based catalysts,such as Pd-based [18][19][20] and Pt-based [21,22] materials,s how high ORR activity and H 2 O 2 selectivity in wide range of pH, but their low abundance and high cost impede the large-scale commercial applications.R ecently,c arbon materials have been identified as the promising electrocatalysts for H 2 O 2 electrosynthesis owing to their low cost, high reusability and adjustable nanostructure/interface. [23][24][25][26][27][28][29][30][31][32][33][34][35] Wherein, the oxygen-doped carbon catalysts have gained the special attentions because of their high H 2 O 2 selectivity during ORR.…”

Synthesis Strategies, Catalytic Applications, and Performance Regulation of Single‐Atom Catalysts

“…[ 110,111 ] It can be concluded that the binding energy difference between HOO* and O* species reflect the ORR selectivity and activity of SACs from several representative works toward two electron ORR for H 2 O 2 electrochemical synthesis. [ 112,113 ] The larger the difference, the better the performance for 2e − ORR, that subsequently Rh SACs showed the highest activity among them. [ 63 ] Recently, various transition metal single atoms (e.g., Fe, Pd, Co, and Mn) coordinated into vacancies of carbon nanotube with O or N coordination have been reported for pathway selection, in which Fe–C–O motifs were responsible for H 2 O 2 pathway that subsequently showed superior performance with an unprecedented onset of 0.822 V versus RHE in alkaline solution at 0.1 mA cm −2 H 2 O 2 current on rotating ring‐disc electrode (RRDE) and a maximum H 2 O 2 selectivity of up to 95% in alkaline or neutral pH.…”

Chemical Identification of Catalytically Active Sites on Oxygen‐doped Carbon Nanosheet to Decipher the High Activity for Electro‐synthesis Hydrogen Peroxide

“…[6][7][8][9][10][11] In recent years,e normous efforts have been devoted to searching for cost-effective and high-performance electrocatalysts to produce H 2 O 2 . [12][13][14][15][16][17] Noble-based catalysts,such as Pd-based [18][19][20] and Pt-based [21,22] materials,s how high ORR activity and H 2 O 2 selectivity in wide range of pH, but their low abundance and high cost impede the large-scale commercial applications.R ecently,c arbon materials have been identified as the promising electrocatalysts for H 2 O 2 electrosynthesis owing to their low cost, high reusability and adjustable nanostructure/interface. [23][24][25][26][27][28][29][30][31][32][33][34][35] Wherein, the oxygen-doped carbon catalysts have gained the special attentions because of their high H 2 O 2 selectivity during ORR.…”