Rational design of C₂N-based type-II heterojunctions for overall photocatalytic water splitting

Abstract

We screened 2D monolayers to explore the materials which could be used to fabricate type-II heterojunctions with C2N monolayers to further improve their photocatalytic performance.

C2N: A Class of Covalent Frameworks with Unique Properties

“…Several theoretical predictions on the ability of C 2 N and metal composites to act as catalysts for diverse applications followed (e.g., HCOOH dehydrogenation, seawater desalination, and photocatalytic and electrocatalytic water splitting activity). [ 67–77 ] The predicted multipodal strong binding sites [ 66 ] play an important role when C 2 N combines with CO 2 , ionic liquids, and metal ions, such that C 2 N exhibits excellent gas adsorption/separation, supercapacitor, and battery performance, [ 38,40 ] which is discussed in detail in subsequent sections. Moreover, due to these unique pores, C 2 N itself can be used as a catalyst as well as a support, which can strongly bind large amounts of single metal atoms.…”

Rotation Tunable Photocatalytic Properties of ZnO/GaN Heterostructures

“…Combining two different semiconductors to construct a heterostructure is an effective strategy for enhancing photocatalytic performance, which should be attributed to the fact that the heterostructure usually has smaller bandgap than the single semiconductor, and the formation of the built‐in electric field in the heterostructure interface area can hinder photogenerated carriers. A series of heterostructures, such as C 2 N/InTe, AlN/WS 2 , MoTe 2 /CrS 2 , GaN/Mg(OH) 2 , MoS 2 /CdS, CdS/C 2 N, CdS/ZnSe, BlueP/Mg(OH) 2 , BiNbO 4 /ZnWO 4 , C 60 /g‐C 3 N 4 , SiC/MoS 2 , and GaN/BlueP, exhibit enhanced photocatalytic performance. Especially, some ZnO monolayer‐based heterostructures are ZnO/MoS 2 , ZnO/WS 2 , ZnO/WSe 2 , ZnO/AlN, and N‐ZnO/g‐C 3 N 4 .…”

High-throughput screening of two-dimensional materials and prediction of photocatalytic performances

“…Xie等人 [85] 研究了不同 数量质子装饰的卟啉的吸收光谱, 随装饰质子数的增 加, 其吸收光谱由于带隙的变宽发生蓝移现象. 2D光 催化剂 [25,45] . 对于光催化剂, 应该尽可能地提高其利用可见光 的能力, 因为它占太阳能的40%以上, 而紫外光则占不 到5% [73] .…”

“…例如, 通过高通量计算, 从数据库中, 筛选出潜在的2D材料 [22] . 随后, 通过第一性原理计算研 究筛选出的2D材料, 可以预测其稳定性 [23] 、带隙 [24] 、 载流子迁移率 [7] 和光吸收性能 [25] , 从而导向性地设计 结构优化的过程中, 利用不同的泛函会得到不同 的优化结果. Qiao等人 [7] 利用基于不同泛函的DFT计算 模拟α-P的几何结构来测试各种泛函的准确性, 结果表…”