Enhanced hydrogen production with photo‐induced phase transformation and cocatalyst loading

Abstract

Summary In this study, reduced graphene oxide (RGO)‐Cd(1 − x)ZnxS nanocomposites have been synthesized with the solvothermal method in one pot. Moreover Pt, Ru, and Rh nanoparticles have been loaded on the RGO‐Cd(1 − x)ZnxS nanocomposites as cocatalysts with the aim of increasing the photocatalytic (PC) performance for hydrogen evolution reaction. The structure of Cd(1 − x)ZnxS blend transforms from cubic to hexagonal structure during the PC hydrogen evolution reaction (PCHER) at the room temperature. This photo‐induced phase transformation (PIPT) enhances not only the hydrogen evolution rate, but also the stability of the photocatalysts. Interestingly, RGO triggers the PIPT process only during the PCHER under solar light illumination. On the other hand, the loading of Pt, Ru, and Rh cocatalysts do not affect the PIPT process. However, they enhance the PC and photoelectrochemical (PEC) hydrogen production activity of RGO‐Cd(1 − x)ZnxS photocatalyst. PEC performance increases about 5.5 times when Pt (5%) and RGO are added to the Cd0.60Zn0.40S catalyst. RGO‐Cd0.60Zn0.40S including 1.5% Rh photocatalyst reaches a remarkable PC hydrogen production rate of 135 μmolh−1 with QE of 23.3% at 460 nm. Therefore, Rh cocatalyst appears as a good alternative to Pt.

Enhance photocatalytic hydrogen evolution by using alkaline pretreated corn stover as a sacrificial agent

“…The photocatalytic reaction is a mild process, which has been extensively studied for contaminant remediation, hydrogen production, carbon dioxide reduction, and fine chemical synthesis . However, because of the combination of hole‐electrons, the efficiency of hydrogen production from pure water splitting is low . As shown in Table , the photocatalytic hydrogen production was promoted when the corn stover was added into the reaction system.…”

“…14,[54][55][56][57][58] However, because of the combination of hole-electrons, the efficiency of hydrogen production from pure water splitting is low. 27,59 As shown in Table 1, the photocatalytic hydrogen production was promoted when the corn stover was added into the reaction system. Furthermore, the tests of photocatalytic hydrogen production, which chose the composition of corn stover such as α-cellulose, glucose (cellulose model compound), xylan (hemicellulose model compounds), lignin (dealkaline), and lignin (alkaline) as a sacrificial agent, were carried out, respectively.…”

Highly efficient photocatalytic H 2 evolution over Ni‐doped Mn 0. 5 Cd 0 . 5 S nanorods under visible light

“…3,4 Many semiconductor material were reported with H 2 production activity, such as TiO 2 , 5,6 g-C 3 N 4 , [7][8][9][10] and so on. 11,12 Among all challenges, developing a highly active photocatalysts has been an urgent concern for achieving industrial application of photocatalytic H 2 production technology.…”

Entangled spintronic modulated high‐performance Ce 2 O 3 small polaron surface state‐based water splitting cells

“…Many scientists put their efforts 3 into finding out the renewable materials or recyclable energy systems [4][5][6] for solving the problems of environmental pollution 7 and the high energy consumption. 8,9 Since pure water and electric power are the products of fuel cells, 10 water splitting cells have been designed to provide hydrogen and oxygen gases by splitting waste water, 9,11,12 which is seen as the best solution for solving the problems of water pollutions and replacing the fossil energy. 13 Among these possible systems, metal-oxide matrixed photo-electrochemical water splitting cell gets solar-to-hydrogen conversion efficiency around 7.5%, which exceed 10% commercial devices.…”

“…Water pollution 1,2 is one of the unstoppable environmental pollutions in the world when the population and industries are nearly uncontrollable growing. Many scientists put their efforts 3 into finding out the renewable materials or recyclable energy systems 4‐6 for solving the problems of environmental pollution 7 and the high energy consumption 8,9 . Since pure water and electric power are the products of fuel cells, 10 water splitting cells have been designed to provide hydrogen and oxygen gases by splitting waste water, 9,11,12 which is seen as the best solution for solving the problems of water pollutions and replacing the fossil energy 13 .…”