Dark Photocatalysis: Storage of Solar Energy in Carbon Nitride for Time-Delayed Hydrogen Generation

Lau, Vincent Wing-hei; Klose, Daniel; Kasap, Hatice; Podjaski, Filip; Pignié, Marie-Claire; Reisner, Erwin; Jeschke, Gunnar and Lotsch, Bettina V. (2017): Dark Photocatalysis: Storage of Solar Energy in Carbon Nitride for Time-Delayed Hydrogen Generation. In: Angewandte Chemie-international Edition, Vol. 56, No. 2: pp. 510-514

Abstract

While natural photosynthesis serves as the model system for efficient charge separation and decoupling of redox reactions, bio-inspired artificial systems typically lack applicability owing to synthetic challenges and structural complexity. We present herein a simple and inexpensive system that, under solar irradiation, forms highly reductive radicals in the presence of an electron donor, with lifetimes exceeding the diurnal cycle. This radical species is formed within a cyanamide- functionalized polymeric network of heptazine units and can give off its trapped electrons in the dark to yield H-2, triggered by a co-catalyst, thus enabling the temporal decoupling of the light and dark reactions of photocatalytic hydrogen production through the radical's longevity. The system introduced here thus demonstrates a new approach for storing sunlight as long-lived radicals, and provides the structural basis for designing photocatalysts with long-lived photo-induced states.

• Item Type: Journal article
• EU Funded Grant Agreement Number: 639233
• EU Projects: Horizon 2020 > ERC Grants > ERC Starting Grant > ERC Grant 639233: Fuel from sunlight: Covalent organic frameworks as integrated platforms for photocatalytic water splitting and CO2 reduction
• Faculties: Chemistry and Pharmacy > Department of Chemistry
• Subjects: 500 Science > 540 Chemistry
• ISSN: 1433-7851
• Language: English