# Noble Metal-Based Heterogeneous Catalysts for Electrochemical Hydrogen Evolution Reaction
## 4 Noble Metal-Based Heterogeneous Catalysts
### Interface Engineering
#### 4.2.2 D Structure Hybrid Nanostructures Loaded with Noble Metals  
The ultrathin 2D nanomaterials have attracted broad attention since [PERSON] et al. [100] mechanically separated graphene from graphite in 2004. In recent years, researchers have developed many ultrathin 2D materials (Figure 8), such as transition metal dichalcogenides, metal-organic frameworks, hexagonal boron nitride, graphite carbon nitride, black phosphorus, MXenes, layered metal oxides and layered double hydroxides [101]. Figure 7: (**a,b**) TEM images and (**c,d**) HRTEM images of 4H/_fcc_ Au@PdAg core-shell nanoribbons. (**e**) Onset potentials and overpotentials (at \(j\) = 10 mA cm\({}^{-2}\)) of Pd black, 4H/_fcc_ Au@PdAg NRB, and Pt black. (**f**) Corresponding Tafel plots. (**g**) Durability test of 4H/_fcc_ Au@PdAg NRB. All measurements were conducted in a 0.5 M H\({}_{2}\)SO\({}_{4}\) aqueous solution [83]. Copyright 2016 American Chemical Society. The electronic confinement of ultrathin 2D nanomaterials without interlayer interaction, especially single-layer nanomaterials, gives them better electronic properties than other nanomaterials. In addition, their large lateral size and atomic layer thickness give them an extremely high specific surface area, exposing more surface atoms, which is ideal for expanding their applications in the field of high surface activity [103; 104]. Based on the above advantages, researchers choose 2D materials as the substrate for noble metals, which can effectively prevent the agglomeration of noble metals in the catalytic process and improve the catalytic performance by exposing the surface active sites. * TMDs, Transition Metal Dichalcogenides  
TMDs are an essential semiconductor material, whose chemical composition is MX2 (M is the transition metal, X is S, Se or Te), and the 2D structural units (such as S-Mo-S) are combined with each other through van der Waals forces, which has broad application prospects in electrocatalysis. At present, noble metal nanoparticles such as Pt, Pd, Ru and Au have been grown on TMDs (such as MoS\({}_{2}\), MoSe\({}_{2}\), WS\({}_{2}\), TiS\({}_{2}\), TaS\({}_{2}\), VS\({}_{2}\) and VSe\({}_{2}\)) for the HER [105; 106]. For example, [PERSON] et al. [85] synthesized epitaxial-grown Pt-MoS\({}_{2}\) composites using the wet chemical method. Under the same Pt loading, the material showed better HER electrocatalytic activity than the commercial Pt catalyst, mainly due to the strong interaction between MoS\({}_{2}\) nanocrystals and Pt nanoparticles, regulating the electronic state of the Pt nanoparticles (Pt\({}^{0}\)\(\rightarrow\) Pt\({}^{8+}\)). * BP, Black Phosphorus  
BP has a layered structure, and the layers are combined by van der Waals forces. When BP and other materials (such as Ni\({}_{2}\)P [107], Co\({}_{2}\)P [108] and MoS\({}_{2}\)[109]) are assembled into heterostructures, the result can promote the performance of electrocatalytic HER. In addition, BP can also be used as a carrier to regulate the electronic structure of noble metals and synergistically promote the HER performance. [PERSON] et al. [94] synthesized the hybrid structure of PtRu nanoclusters (NCs) and BP nanosheets (Figure 9a), which showed 10.2 times higher HER activity (\(\eta_{10}\) = 22 mV; Tafel slope = 19 mV dec\({}^{-1}\)) than that of commercial Pt/C (Figure 9b) in 1 M KOH. The DFT calculations showed that the electronic synergy effect resulting from the strong electron coupling between BP nanosheets and PtRu nanoclusters accelerated the water dissociation, optimized the adsorption strength of H* and enabled the PtRu NCs/BP hybrid material to have high HER activity (Figure 9c,d). Figure 8: Schematic illustration of different kinds of typical ultrathin 2D nanomaterials, such as TMDs, BP, MXene, LDHs, MOFs and graphene [101; 102]. Copyright 2013 Royal Society of Chemistry; 2015 American Chemical Society. * MXene As typical 2D functional materials, MXene has attracted wide attention in the fields of renewable energy and catalysis [110].