Biohybrid Organic Heterostructure Based on Chlorophyll‐Bacteriochlorophyll Aggregates for Ecofriendly Hydrogen Production

Abstract

Hydrogen energy is an abundant, clean, sustainable and environmentally friendly renewable energy source. Therefore, the production of hydrogen by photocatalytically splitting water on semiconductors has been considered in recent years as a promising and sustainable strategy for converting solar energy into chemical energy to replace conventional energy sources and to solve the growing problem of environmental pollution and the global energy crisis. However, highly efficient solar-driven photocatalytic hydrogen production remains a huge challenge due to the poor visible light response of available photocatalytic materials and the low efficiency of separation and transfer of photogenerated electron-hole pairs. In the present work, organic heterojunction structures based on bacteriochlorophyll (BChl) and chlorophyll (Chl) molecules were introduced and used for solar-driven photocatalytic hydrogen production from water under visible light. Also, noble metal-free photocatalyst was successfully constructed on Ti 3 C 2 T x nanosheets by simple successive deposition of Chl and BChl, which was used for the photocatalytic splitting water to hydrogen evolution reaction (HER). The results show that the optimal BChl@Chl@Ti 3 C 2 T x composite has a high HER performance with 114 μmol/h/g cat , which is much higher than the BChl@Ti 3 C 2 T x and Chl@Ti 3 C 2 T x composites.

Biohybrid Molecule‐Based Photocatalysts for Water Splitting Hydrogen Evolution

“…Subsequently, Li et al replaced the Chl-2 in the previous research with another chlorophyll derivate BChl, of which the HOMO and LUMO are both higher than the Chl-1, and constructed another photocatalytic system. [90] The Z-scheme electron transport process proved to be feasible when employed in a Chl-based photocatalyst system based on previous research, and the novel organic-inorganic heterojunction photocatalytic system (BChl/Chl-1/Ti 3 C 2 T x ) also can be explained in similar way (Figure 14). Due to the interleaved energy band structure, photogenerated electrons can easily transfer from the LUMO of BChl to the LUMO of Chl and then to the surface of Ti 3 C 2 T x to recombine of the H + ions due to high conductivity of Ti 3 C 2 T x , while the holes can transfer from the HOMO of Chl to the HOMO of BChl and later gain electrons from the sacrificial agent.…”

“…Subsequently, Li et al. replaced the Chl‐2 in the previous research with another chlorophyll derivate BChl, of which the HOMO and LUMO are both higher than the Chl‐1, and constructed another photocatalytic system [90] . The Z‐scheme electron transport process proved to be feasible when employed in a Chl‐based photocatalyst system based on previous research, and the novel organic‐inorganic heterojunction photocatalytic system (BChl/Chl‐1/Ti 3 C 2 T x ) also can be explained in similar way (Figure 14).…”

Efficient photocatalytic hydrogen production by organic–inorganic heterojunction structure in Chl@Cu2O/Ti3C2Tx

“…28 MXenes, a new family of novel two-dimensional (2D) materials, first reported by Gogotsi in 2011, have the general formula M n+1 X n T x , where M represents for an early transition metal element, X for carbon or nitrogen, and T for a surface termination group. [29][30][31] Ti 3 C 2 T x , as a common MXene material, has been widely investigated in solar cells, 32 energy storage 33 and photocatalysis [34][35][36][37] due to its non-precious metal, excellent electrical conductivity, strong work function, large specific surface area and the presence of a large number of hydrophilic groups. The Ti 3 C 2 T x MXene co-catalyst with metallic properties was coupled with a Cu 2 O semiconductor in order to construct a Schottky junction photocatalytic system.…”

Mechanistic insights into photoinduced energy and charge transfer dynamics between magnesium-centered tetrapyrroles and carbon nanotubes

“…7,8 These magnesium-centered tetrapyrroles with an extended p electron system possess remarkable absorption capacities in the visible light region, making them ideal candidates as photosensitizers in photodynamic therapy (PDT), photocatalysis, etc. 9,10 Single-walled carbon nanotubes (SWNTs) are rapidly finding their way into nanoscale optoelectronic devices nowadays because of their large surface areas and superior charge transport properties. [11][12][13][14] What's more, the properties of SWNTs can be flexibly tailored by functionalizing with special organic molecules.…”

“…7,8 These magnesium-centered tetrapyrroles with an extended π electron system possess remarkable absorption capacities in the visible light region, making them ideal candidates as photosensitizers in photodynamic therapy (PDT), photocatalysis, etc. 9,10…”