Density functional theory (DFT) calculations have revealed the essential nature of bond relaxation and electronic reconfiguration in (GaAs, Graphene, InSe)-(WS2, MoS2) layered heterojunctions. The bandgap lies within the range 0.01 similar to 1.0 eV, which may be suitable for photocatalytic applications. We have also established a relationship between the atomic coordination density and the surface strain of two-dimensional heterojunctions. Moreover, the interfacial atomic cohesive energy and the bond energy density varies from case to case. These findings may lead to new materials for related fields.