TiO₂ Photonic Crystal Sensitized with Mn₃O₄ Nanoparticles and Porphine Manganese(III) as Efficient Photoanode for Photoelectrochemical Water Splitting

Abstract

We report the synthesis and photoelectrochemical characterization of a novel composite consisting of Mn 3 O 4 nanoparticles, porphine manganese(III) (PMA), and TiO 2 photonic crystal (TPC). The prepared composite (Mn 3 O 4 /PMA/TPC) was used for fabricating the photoanode of a photoelectrochemical tandem cell. The obtained Mn 3 O 4 /PMA/TPC composite was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and UV−vis diffuse reflectance spectroscopy (DRS). The results demonstrated that PMA and Mn 3 O 4 nanoparticles had been loaded in the hole of TPC successfully. The photoelectrochemical characterization of the Mn 3 O 4 /PMA/TPC electrode revealed an enhanced light harvesting and effective electron−hole separation. The photoelectrochemical tandem cell, of which Mn 3 O 4 /PMA/TPC electrode acted as a photoanode and a Pt plate as counter electrode, was used to evaluate the feasibility for water splitting to produce H 2 and O 2 under a 300 W solar simulator irradiation. The gases evolved from the system when the applied voltage was 1.0 V (vs RHE). The evolution amount of hydrogen and oxygen can reach to 12.2 μmol and 4.4 μmol, respectively, under 4 h simulated solar-light irradiation. The possible mechanism of the surface modification effects was proposed. The results suggest that Mn 3 O 4 nanoparticles and PMA modified TPC can act as efficient catalyst for fabricating photoanode in a photoelectrochemical tandem cell.

Recent Advances in Preparation and Applications of 3D Transition Metal Oxides Semiconductor Photonic Crystal

“…The sol-gel method is the most common preparation method for the 3D TMOPCs. [53][54][55][56][57][58] The compounds containing high-chemical active components are used as precursor mixed in the liquid phase. Then, a stable transparent sol system is formed by hydrolysis and condensation chemical reactions in the solution.…”

Visible Light Trapping against Charge Recombination in FeOx–TiO2 Photonic Crystal Photocatalysts

“…Besides extending the optical path of incident photons, PC structures, the most common being inverse opals as well as periodically ordered alumina and GaN structures tailored by electrochemical anodization [ 21 , 22 , 23 ], provide a macroporous scaffold that along with the secondary mesoporosity of its inorganic skeleton lead to a network of interconnected macro-mesopores [ 24 ], which facilitate reactants adsorption and diffusion during the photocatalytic process [ 25 ]. Substantial research has been thus devoted to exploiting these advantageous characteristics in combination with materials’ compositional properties in order to develop visible light-activated (VLA) photonic photocatalysts [ 26 ], including coupling PCs with plasmonic [ 27 , 28 , 29 , 30 ] and graphene nanomaterials [ 31 , 32 , 33 ] as well as metal-oxide (MO) nanoclusters [ 34 , 35 , 36 ].…”

Benchmarked Photoelectrochemical Water Splitting by Nickel-Doped n-Type Cuprous Oxide

“…However, the production of hydrogen currently relies largely on fossil fuel using steam reforming of methane, wherein carbon dioxide is emitted as the byproduct. To address this issue, a photoelectrochemical approach for hydrogen generation using renewable sunlight and clean water was put forward. − In such a scheme, cuprous oxide (Cu 2 O) grabs respectable attention, provided that its high absorption coefficient of 10 5 cm –1 and direct band gap of approximately 2.1 eV allow this material to make full use of diffuse sunlight to achieve excellent solar-to-hydrogen conversion efficiency. − This is manifested in a recent publication by Luo et al, wherein a state-of-the-art photocurrent of −10 mA cm –2 was delivered by Cu 2 O having p-type conduction, so it was accordingly employed as the photocathode along with TiO 2 and RuO x functioning as the protective and catalytic layers on the surface, respectively . Such significant achievement in turn stimulates tremendous interests in Cu 2 O that otherwise has n-type conductivity and therefore works alternatively as an anode to photoelectrochemically split water for hydrogen generation.…”