Near‐Infrared‐Light‐Driven Artificial Photosynthesis by Nanobiocatalytic Assemblies

Abstract

Artificial photosynthesis in nanobiocatalytic assemblies aims to reconstruct man-made photosensitizers, electron mediators, electron donors, and redox enzymes for solar synthesis of valuable chemicals through photochemical cofactor regeneration. Herein, we report, for the first time, on nanobiocatalytic artificial photosynthesis in near-infrared (NIR) light, which constitutes over 46% of the solar energy. For NIR-light-driven photoenzymatic synthesis, we synthesized silica-coated upconversion nanoparticles, Si-NaYF4:Yb,Er and Si-NaYF4:Yb,Tm, for efficient photon-conversion through Förster resonance energy transfer (FRET) with rose bengal (RB), a photosensitizer. We observed NIR-induced electron transfer by using linear sweep voltammetric analysis; this indicates that photoexcited electrons of RB/Si-NaYF4:Yb,Er are transferred to NAD+ through a Rh-based electron mediator. RB/Si-NaYF4:Yb,Er nanoparticles, which exhibit higher FRET efficiency due to more spectral overlap than RB/Si-NaYF4:Yb,Tm, perform much better in the photoenzymatic conversion.

In Situ Prepared Flexible 3D Polymer Film Photocatalyst for Highly Selective Solar Fuel Production from CO2

“…An increase in reduction peak potential of 3DAP‐ M at −1.1 V vs. Ag/AgCl upon addition of NAD + implied that the 3DAP‐ M system was able to catalyze the reduction of NAD + (Figure S3, Supporting Information). The nonappearance of any additional oxidation peak further showed that the 3DAP‐M followed the electrochemistry of M . Based on these observations one can conclude that following the photoexcitation of the 3DAP electron from the highest occupied molecular orbital HOMO (E=−5.9 eV vs. vaccum level) to the lowest unoccupied molecular orbital LUMO (E=−3.25 eV vs. vaccum level), it is transferred to M (Figure ) .…”

“…The nonappearance of any additional oxidation peak further showed that the 3DAP‐M followed the electrochemistry of M . Based on these observations one can conclude that following the photoexcitation of the 3DAP electron from the highest occupied molecular orbital HOMO (E=−5.9 eV vs. vaccum level) to the lowest unoccupied molecular orbital LUMO (E=−3.25 eV vs. vaccum level), it is transferred to M (Figure ) . The vicinity and potential gradient between the visible light responsive 3DAP photocatalyst and electro‐catalytic M center enables the electron transfer from the former to the latter.…”

TiO2‐Based Photocatalysis at the Interface with Biology and Biomedicine

“…The NIR‐responsive nanocomposites are effective in killing cancer cells in vitro and even in vivo (Figure ). However, some of their limitations are the lack of uniformity in size and shape, and the difficulty in controlling the amount of PS loaded in close proximity to the UC NP constructs, which is very important for efficient UC and the generation of ROS . To overcome these limitations, researchers have used a continuous layer of PS (TiO 2 ) individually coated on each UC NP core to give a well‐defined core–shell structure, with uniform size, shape, and dispersion.…”

“…However,s omeo ftheir limitations are the lack of uniformity in size and shape, and the difficulty in controlling the amount of PS loadedi nc lose proximity to the UC NP constructs, which is very important for efficient UC and the generation of ROS. [80,81] To overcomet hese limitations, researchers have used ac ontinuous layer of PS (TiO 2 )i ndividually coated on each UC NP core to give aw ell-defined core-shell structure, with uniform size, shape, and dispersion. This allows controllable and uniform TiO 2 loading onto individual UC NP cores, ande liminates the possibility of PS leakage;t hus ensuring significant ROS generation for effective and repeatable PDT.…”

Photobiocatalysis: The Power of Combining Photocatalysis and Enzymes

“…It would be also important if this large proportion of NIR energy present in the sunlight could be used in photobiocatalysis. In one clever approach aimed at utilization of NIR wavelengths, Park and coworkers [69] have prepared nanoparticles of NaYF 4 (Taken with permission from ref [69] ).…”