Integration of Artificial Photosynthesis System for Enhanced Electronic Energy‐Transfer Efficacy: A Case Study for Solar‐Energy Driven Bioconversion of Carbon Dioxide to Methanol

Abstract

Biocatalyzed artificial photosynthesis systems provide a promising strategy to store solar energy in a great variety of chemicals. However, the lack of direct interface between the light-capturing components and the oxidoreductase generally hinders the trafficking of the chemicals and photo-excited electrons into the active center of the redox biocatalysts. To address this problem, a completely integrated artificial photosynthesis system for enhanced electronic energy-transfer efficacy is reported by combining co-axial electrospinning/electrospray and layer-by-layer (LbL) self-assembly. The biocatalysis part including multiple oxidoreductases and coenzymes NAD(H) was in situ encapsulated inside the lumen polyelectrolyte-doped hollow nanofibers or microcapsules fabricated via co-axial electrospinning/electrospray; while the precise and spatial arrangement of the photocatalysis part, including electron mediator and photosensitizer for photo-regeneration of the coenzyme, was achieved by ion-exchange interaction-driven LbL self-assembly. The feasibility and advantages of this integrated artificial photosynthesis system is fully demonstrated by the catalyzed cascade reduction of CO2 to methanol by three dehydrogenases (formate, formaldehyde, and alcohol dehydrogenases), incorporating the photo-regeneration of NADH under visible-light irradiation. Compared to solution-based systems, the methanol yield increases from 35.6% to 90.6% using the integrated artificial photosynthesis. This work provides a novel platform for the efficient and sustained production of a broad range of chemicals and fuels from sunlight.

Opportunities and challenges for combining chemo- and biocatalysis

“…Combining the realms of photo-/electrocatalysis with biocatalysis, two benchmark contributions in the field for the reduction of CO 2 to methanol were reported by Ji et al 44 and Kuk et al 53 . Both systems combined three dehydrogenases in a cascade reaction to achieve methanol formation.…”

Green synthesis of enzyme/metal-organic framework composites with high stability in protein denaturing solvents

“…One of the important aims of enzyme immobilization is to achieve high enzyme stability at harsh conditions such as high temperature and organic solvents which often existe in industrial biocatalytic processes. Although immobilization may compromise the activity of enzyme, the greatly enhanced stability would enable the long-term and repeated use of enzyme and therefore a significantly reduced cost of enzyme (Liu et al 2015; Liang et al 2016a; Ji et al 2016; Novak et al 2015). Metal-organic frameworks (MOFs) have emerged as a new type of nanomaterials suitable for immobilization of enzyme (Feng et al 2015; Lykourinou et al 2011; Chen et al 2012; Wen et al 2016) and other biomolecules (Zhang et al 2016; Li et al 2016a, b).…”

Photobiokatalyse: Aktivierung von Redoxenzymen durch direkten oder indirekten Transfer photoinduzierter Elektronen

“…[141] Aufgrund ihrer hohen Spezifität, Effizienz und der milden Reaktionsbedingungen werden Redoxenzyme wie FDH als nachhaltige Katalysatoren in der photogetriebenen Reduktion von CO 2 eingesetzt. [147,148] Abbildung 12. [144][145][146] Dementsprechend ist eine effiziente Kopplung der katalytischen Reaktion der FDH an die photogetriebene Regeneration von NADH nçtig, um eine photoenzymatische CO 2 -Reduktion zu ermçglichen.…”

“…Die durchschnittlichen Umsatzraten der Methanolproduktion des PEC-Systems lagen bei 220 mm h À1 in Bezug auf das Reaktionsvolumen und bei 1.280 mm g cat À1 h À1 in Bezug auf das Gewicht des eingesetzten Katalysators.D amit lagen diese Umsatzraten bis zu 30-mal hçher als in anderen photoenzymatischen Systemen, welche TEOAals Elektronendonor in der Umwandlung von CO 2 zu Methanol einsetzen [147,148]. In einer Folgearbeit wurde ein mit Sonnenlicht belichtetes biokatalytisches PEC-System mit einem Solartrackermodul etabliert, das an sonnigen Tagen mit einer TOFvon 14.4 h À1 Formiat erzeugte.…”