3D Graphene‐Based H₂‐Production Photocatalyst and Electrocatalyst

Abstract

Hydrogen (H2) has been deemed as the most promising and valuable alternative to nonrenewable fossil fuels. Photocatalytic and electrocatalytic water splitting are considered to be the most efficient and environmentally friendly approaches for the sustainable H2 evolution reaction (HER). Graphene with a 3D framework has been utilized for the HER due to its unique structure and properties, including its hierarchical network, large specific surface area, diverse pore distribution, outstanding light absorption ability, and excellent electrical conductivity. The large specific surface area and hierarchically porous structure of 3D graphene can not only maximize the exposure of active sites but also promote electron transfer and gas product diffusion. In addition, the free‐standing 3D graphene monolith is easily recycled compared with powder phase support, which can prevent the loss of active catalysts. By making full use of the aforementioned merits, 3D graphene‐based composite materials show great promise as high‐performance catalysts toward photocatalytic and electrocatalytic HER. In this review, recent advances in fabricating 3D graphene‐based composite materials and their applications in both photocatalytic and electrocatalytic HER are summarized and discussed. Furthermore, the current challenges and future vision associated with the design, fabrication, and integration of 3D graphene‐based composite materials toward HER are put forward.

Sustained CO2-photoreduction activity and high selectivity over C, Mn-codoped ZnO core-triple shell hollow spheres

“…Whereas the latter reduces both diffusion lengths of charges and reactants, thus minimizing charges recombination opportunities and provide accessible channels for mass/charge transfer. 54 TRPL results also demonstrate that 2% Mn, C-ZnO can retard charge carriers recombination and prolong their lifetime (average charge carrier-lifetime ca. 1.1, 0.9 and 0.8 ns for 2%Mn, C-ZnO, C-ZnO and Comm.…”

Nanostructured CdS for efficient photocatalytic H2 evolution: A review

“…Additionally, it is well known that nanocarbon mate-rials (e.g., graphene [291,[315][316][317][318][319], carbon quantum dots [211,236,257,320,321], carbon black [322], carbon fiber [323][324][325] and carbon nanotubes [78,[326][327][328]) have been considered as outstanding promoters for photocatalytic performances. The attraction is attributed to their superior adsorption capacity, unique electronic conductivity, nontoxicity, low cost, high stability, and large surface area.…”

Recent progress in Bi2WO6‐Based photocatalysts for clean energy and environmental remediation: Competitiveness, challenges, and future perspectives

“…3D nanostructures are generally assembled with low‐dimensional structures. [ 70–76 ] 3D hierarchical nanostructures or microstructures, can not only overcome the issue of acute agglomeration in low‐dimensional but also fuse the properties of both nanoscale materials. Moreover, the photocatalysts with 3D hierarchical nanostructures or microstructures have the following characteristics: an abundance of surface active sites and high light absorption.…”

“…Additionally, we deeply illustrate and analyze the connections between the morphological, photophysics and photochemical properties of Bi 2 WO 6 , which include dopant or defect structures, metal deposition techniques, semiconductor combinations and surface modification by carbon‐based materials with conjugated π‐structures. [ 39–181 ] We critically review the practical applications of water splitting, pollutant removal, and especially CO 2 reduction. These aspects reflect the research status of Bi 2 WO 6 , as well as its potential and opportunities in the field of clean energy and environmental protection.…”