The photocatalyst-enzyme coupled system for artificial photosynthesis process is one of the most promising methods of solar energy conversion for the synthesis of organic chemicals or fuel. Here we report the synthesis of a novel graphene-based visible light active photocatalyst which covalently bonded the chromophore, such as multianthraquinone substituted porphyrin with the chemically converted graphene as a photocatalyst of the artificial photosynthesis system for an efficient photosynthetic production of formic acid from CO(2). The results not only show a benchmark example of the graphene-based material used as a photocatalyst in general artificial photosynthesis but also the benchmark example of the selective production system of solar chemicals/solar fuel directly from CO(2).

Order/disorder interfacial engineering realizes highly efficient co-catalyst free hydrogen generation.

Hydrogen has been touted as an energy carrier of the future because it combines with oxygen to produce only water with no greenhouse gases or other pollutants. For hydrogen to play the role, it must be produced in a sustainable manner from a renewable energy source, such as solar energy. [1] Unlike the electricity produced from the most common photovoltaic cells, hydrogen could store the solar energy in the form of chemical energy. One of the most attractive solar energy conversion reactions is the photoelectrochemical (PEC) or photocatalytic water splitting directly to H 2 and O 2 . Since its initial demonstration by Fujishima and Honda with a TiO 2 electrode under ultraviolet light, [2] there has been steady progress in this field in search of semiconductor photocatalytic electrode materials that work under visible light irradiation for ample solar light absorption. However, the photocatalysts with high efficiency, durability, and economic feasibility are still elusive. [3,4] Scheelite-monoclinic BiVO 4 (mBiVO 4 ) is a well-known photocatalyst, which absorbs visible light owing to a suitable band-gap energy (E g % 2.4 eV). [5,6] It is also nontoxic and chemically stable in aqueous solution under irradiation. However, pristine mBiVO 4 usually shows a low photocatalytic activity owing to poor charge-transport characteristics [7] and the weak surface adsorption properties. [8] Numerous attempts have been made to improve the photocatalytic activity of BiVO 4 , including heterojunction structure formation, [7,9,10] loading co-catalysts, [11][12][13] and impurity doping. [8,14,15] Impurity doping, that is, the addition of a small percentage of foreign atoms in the regular crystal lattice of semiconductors, produces dramatic changes in their electrical properties by increasing their electron or hole densities. In photocatalysis by BiVO 4 , for example, doping with molybdenum to replace a small fraction of vanadium was found to improve the photocatalytic activity for water oxidation. [8,14,15] Phosphorus is a typical dopant for silicon or germanium to make it an n-type semiconductor. However, it has been rarely used as dopant for semiconductor photocatalysts. This is rather surprising because other non-metallic elements, such as N, C, and S, have been widely used as anionic dopants for photocatalysts to reduce their band-gap energies. [16] In the present work, for the first time we doped phosphorous into the vanadium sites in the host lattice of BiVO 4 , replacing some of the VO 4 oxoanions in BiVO 4 with PO 4 oxoanions. Oxoanion doping into the photocatalyst is to the best of our knowledge also a new concept. Herein we report effects of PO 4 oxoanion doping on the photoelectrochemical or photocatalytic behavior of mBiVO 4 under visiblelight illumination. The PO 4 oxoanion doping did not bring about significant changes in the optical absorption behavior and crystal structure of mBiVO 4 . When an appropriate amount PO 4 oxoanion was doped, however, the activity of photoelectrochemical water oxidation increased very sign...

The successful development of a photocatalyst/biocatalyst integrated system that carries out selective methanol production from CO2 is reported herein. The fine-tuned system was derived from a judicious combination of graphene-based visible light active photocatalyst (CCG-IP) and sequentially coupled enzymes. The covalent attachment of isatin-porphyrin (IP) chromophore to chemically converted graphene (CCG) afforded newly developed CCG-IP photocatalyst for this research endeavor. The current work represents a new benchmark for carrying out highly selective methanol formation from CO2 in an environmentally benign manner.

The successful development of a triazine based covalent organic framework as an inexpensive and highly efficient visible light active flexible film photocatalyst for solar fuel production from CO2is described.