Optically and Electrocatalytically Decoupled Si Photocathodes with a Porous Carbon Nitride Catalyst for Nitrogen Reduction with Over 61.8% Faradaic Efficiency

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

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Author(s)

  • Karthik Peramaiah
  • Vinoth Ramalingam
  • Hui-Chun Fu
  • Merfat M. Alsabban
  • Rafia Ahmad
  • Luigi Cavallo
  • Vincent Tung
  • Kuo-Wei Huang

Detail(s)

Original languageEnglish
Article number2100812
Journal / PublicationAdvanced Materials
Volume33
Issue number18
Online published31 Mar 2021
Publication statusPublished - 6 May 2021

Abstract

The photoelectrochemical (PEC) approach is attractive as a promising route for the nitrogen reduction reaction (NRR) toward ammonia (NH3) synthesis. However, the challenges in synergistic management of optical, electrical, and catalytic properties have limited the efficiency of PEC NRR devices. Herein, to enhance light-harvesting, carrier separation/transport, and the catalytic reactions, a concept of decoupling light-harvesting and electrocatalysis by employing a cascade n+np+-Si photocathode is implemented. Such a decoupling design not only abolishes the parasitic light blocking but also concurrently improves the optical and electrical properties of the n+np+-Si photocathode without compromising the efficiency. Experimental and density functional theory studies reveal that the porous architecture and N-vacancies promote N-2 adsorption of the Au/porous carbon nitride (PCN) catalyst. Impressively, an n+np+-Si photocathode integrating the Au/PCN catalyst exhibits an outstanding PEC NRR performance with maximum Faradaic efficiency (FE) of 61.8% and NH3 production yield of 13.8 μg h-1 cm-2 at -0.10 V versus reversible hydrogen electrode (RHE), which is the highest FE at low applied potential ever reported for the PEC NRR.

Research Area(s)

  • decoupling light-harvesting and electrocatalysis, nitrogen reduction, photoelectrochemical, porous carbon nitride

Citation Format(s)

Optically and Electrocatalytically Decoupled Si Photocathodes with a Porous Carbon Nitride Catalyst for Nitrogen Reduction with Over 61.8% Faradaic Efficiency. / Peramaiah, Karthik; Ramalingam, Vinoth; Fu, Hui-Chun et al.
In: Advanced Materials, Vol. 33, No. 18, 2100812, 06.05.2021.

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review