Owing to their unique properties compared with conventional bulk analogues, two-dimensional (2D) nanomaterials, having nano-scale thickness and infinite length, are attracting increasing attention for their potential application in the fields of electronics, sensing, energy storage, and conversion. [1][2][3][4][5][6][7][8] In particular, transition-metal chalcogenides [9][10][11][12][13][14][15] and metal oxide [16] nanosheets are highly promising functional 2D nanomaterials, however, their synthesis in a large scale remains a great challenge. Graphene, a 2D "aromatic" monolayer of carbon material having an ultralight weight, high surface area, and electric conductivity, has emerged as an ideal substrate for the growth and anchoring of functional nanomaterials, such as metal oxide/hydroxide nanoparticles (MO/MH NPs). [3,[17][18][19] The strong coupling between MO/MH NPs and graphene in a confined 2D manner gives nanohybrids with unique structural features and synergistic physical and electrochemical properties derived from both counterparts. [20][21][22][23] Along this line, numerous 2D functional nanohybrids comprising MO/MH NPs and graphene have been successfully constructed. [24][25][26][27] Nevertheless, owing to the general incompatibility between graphene and inorganic NPs under synthetic conditions, the growth of MO/MH NPs on a graphene substrate with uniform morphology, controllable particle size, and enhanced coupling effects constitutes a highly desirable synthetic target.Polyaniline (PANI) is a typical low-cost conducting polymer that can be readily shaped into multiform morphologies, such as fibers/tubes, [28,29] dots/shells, [30] and other oriented nanostructures. [31] Hydrothermal treatment has proven to be an excellent strategy for fabricating PANI NPs. [32] Therefore, given that the protonated nitrogen atoms in PANI can bind with metal ions and mediate their hydrolysis process during hydrothermal treatment, we imagined that graphene-supported PANI nanosheets can facilitate the growth of MO and MH nanocrystals, and thus give rise to ternary nanohybrid sheets with a uniform distribution of hybrid NPs.Herein, we demonstrate an efficient and universal strategy for the controlled growth of MO/MH (such as Co 3 O 4 , Fe 2 O 3 , and Ni(OH) 2 ) NPs on graphene to construct unique 2D nanohybrids employing PANI as the coupling linker between the two components. These nanohybrids have a welldefined 2D morphology, confined MO/MH NPs within the PANI nanostructures, controllable particle size, and high specific surface areas. The fabricated ternary hybrids of graphene, PANI, and Co 3 O 4 (G-PANI-Co 3 O 4 ) with a particle size of 6 to 10 nm deliver excellent rate capability and cycle performance when used as electrode materials for supercapacitors. Further, thermal treatment of G-PANI-MOs/MHs under inert gas yields nitrogen-doped carbon nanosheets integrated with size-controlled metal NPs (GNC-M). For example, N-doped carbon nanosheets supported by 3 to 5 nm sized cobalt NPs (GNC-Co) are synthesized by pyrolysis...

3D macroporous graphene/SnO2 frameworks (MGTFs) are fabricated by amphiphilic polymer-promoted assembly method, which exhibit controllable macroporous structure and outstanding lithium storage performance.

We demonstrate a general and efficient self-templating strategy towards transition metal-nitrogen containing mesoporous carbon/graphene nanosheets with a unique two-dimensional (2D) morphology and tunable mesoscale porosity. Owing to the well-defined 2D morphology, nanometer-scale thickness, high specific surface area, and the simultaneous doping of the metal-nitrogen compounds, the as-prepared catalysts exhibits excellent electrocatalytic activity and stability towards the oxygen reduction reaction (ORR) in both alkaline and acidic media. More importantly, such a self-templating approach towards two-dimensional porous carbon hybrids with diverse metal-nitrogen doping opens up new avenues to mesoporous heteroatom-doped carbon materials as electrochemical catalysts for oxygen reduction and hydrogen evolution, with promising applications in fuel cell and battery technologies.

Three-dimensional (3D) macroporous graphene aerogel-supported Fe5(PO4)4(OH)3·2H2O (iron(iii) hydroxide phosphate dihydrate) microspheres (GA/IHPDs) have been fabricated by the hydrothermal mineralization of Fe3+ and PO43− ions in the presence of graphene oxide (GO).