Visualizing the Interfacial Charge Transfer between Photoactive Microcystis aeruginosa and Hydrogenated TiO₂

Abstract

Exploring photoactive biotic–abiotic conjugations is of great importance for a variety of applications, but it remains difficult to probe the interfacial transfer of photoinduced charge carriers. In this work, Kelvin probe force microscopy, together with fluorescence imaging technique, were used to visually observe the spatial distribution and interfacial behavior of photocarriers in Microcystis aeruginosa/TiO2 hybrids. Experimental investigations suggested that photosynthetic microalgae cells were prone to trap photoholes from TiO2 photocatalysts. Oxygen vacancy defects in semiconductor exhibited significant impact on the charge migration, as the surface photovoltage of hydrogenated TiO2/microalgae hybrid was much higher than the pristine system. Profiting from the bioenhanced charge separation, biotic–abiotic architecture presented remarkably increased activity for photocatalytic inactivation of microalgae microorganisms. This work not only highlights the visual techniques for understanding the charge transfer around biotic–abiotic interface, but also provides a bioenhanced conjugation for the photocatalytic elimination of microorganisms in water treatment applications.

Development of biophoto anodes usingUlvophyceae macroalgae

“…7 The ability to produce energy from photosynthesis has been studied in subcellular clusters such as isolated photosystems I and II, [8][9][10][11] thylakoid membranes, [12][13][14][15][16][17][18][19] chloroplasts, [20][21][22] as well as various photosynthetic microorganisms such as cyanobacteria 4,[23][24][25] or microalgae. [26][27][28][29] Since the mentioned subcellular structures present few barriers, electrons can be transferred to the external component as electrodes more quickly and efficiently than from complete cell structures. 4 Nonetheless, their extraction and purication processes make them more expensive and fragile, suffering from long-term instability due to the unfavorable environment.…”

Novel TiO2/TPU composite fiber-based smart textiles for photocatalytic applications

“…[1][2][3][4][5][6] Currently, TiO2 photocatalysis is actively used in the field of photodegradation of organic compounds, specifically in environmental decontamination of wastewater, which also suffers these problems. [7][8][9][10][11] During practical application, photocatalysts exist as a powder in the water system, ensuring a high number of photoactive sites and optimizing mass transfer. 12 However, nanophotocatalysts also have some drawbacks.…”

Hydrogenated Amorphous Titania with Engineered Surface Oxygen Vacancy for Efficient Formaldehyde and Dye Removals under Visible-Light Irradiation

“…In order to pursue the best performance in solar energy conversion and utilization, one of the most effective approaches in tuning the band structure and maximizing solar energy capture is O V defect engineering of TiO 2 [ 6 , 7 , 8 , 9 ]. Among considerable strategies in O V defect engineering, the most representative and effective one is thermal hydrogenation of crystallized TiO 2 , which promotes the generation of O V -doped disordered surface at crystalline TiO 2 , i.e., a disordered surface at the crystalline core [ 9 , 10 , 11 , 12 ]. This unique configuration not only provides additional O V -induced states to absorb long-wavelength light, thereby enabling colorful TiO 2−x , but also encourages photoinduced charge separation to achieve superior visible-light photoactivity [ 13 , 14 , 15 ].…”