Here we would like to review our recent progresses on the photonic applications of graphene and other two-dimensional (2D) layered materials. Firstly, we report the development of new saturable absorbers based on graphene heterostructures and other 2D materials, including graphene/Bi2Te3, black phosphorus and self-doped plasmonic 2D Cu3-xP nanosheets. Depending on their nonlinear optical properties, both high energy Q-switched laser and ultrafast mode-locked pulse generation were demonstrated. Secondly, we fabricated a highly efficient hybrid photodetector that consists of graphene covered with dispersive organolead halide perovskite (CH3NH3PbBr2I) islands. We also demonstrated a broadband photodetector based on graphene-Bi2Te3 heterostructure. Furthermore, we developed new methods to grow and transfer large area single crystal WS2, large area MoS2/WS2 heterojunction, and monolayer-bilayer WSe2 heterojunction, and demonstrated their applications for photodetectors. Thirdly, we investigated plasmonic excitation and THz modulation in graphene/Bi2Te3, graphene nanoribbon and 3D graphene using either spectroscopic or real space imaging techniques. The important discoveries include the plasmonic coupling of two Dirac materials, excitation of high-order mode and edge chirality-related plasmonic broadening. Last, we report our recent progress on the synthesis of 2D organic-inorganic hybrid perovskite nanosheets as well as their optoelectronic applications. In summary, the advances of photonics of 2D materials may pave the way for the integration of next generation hybrid silicon photonic circuit.