Microporous and Mesoporous Materials xxx (xxxx) xxx Please cite this article as: Mohammad Yeganeh Ghotbi, Microporous and Mesoporous Materials, https://doi.org/10.1016/j.micromeso.2019.109791 Available online 3 October 2019 1387-1811/© 2019 Elsevier Inc. All rights reserved. A casting strategy to produce 3D bulk monolithic carbon and N-doped carbon nanosheets with high surface area and low volume Mohammad Yeganeh Ghotbi a, * , Arash Javanmard a , Hassan Soleimani b a Materials Engineering Department, Faculty of Engineering, Malayer University, Malayer, Iran b Fundamental and Applied Science Department, Universiti Teknologi PETRONAS, Seri Iskandar, 31750, Malaysia A R T I C L E INFO Keywords: 3D carbon Nitrogen-doped carbon Nanoreactor Porous materials Layered hydroxides ABSTRACT Due to the importance of the 3D carbon monoliths and their vast applications in electrochemical energy, catalysis and gas reservoir devices, different strategies have been made on the synthesis/fabrication of 3D graphene or graphene-like products. Nevertheless, the existing 3D carbon bodies mostly suffer from low accessible surface area (ASA), poor mechanical properties and above all, high volume values, in spite of the today’s need for making small architectures. Moreover, synthesis/fabrication approaches of desirable 3D bodies with particular size and shape remain unavailable, yet. Herein, we report a new simple method based on the idea of layered nanohybrids/nanoreactors for simultaneous synthesis and fabrication of 3D monolithic bodies composed of pure and N-doped carbon nanosheets. X-ray diffraction, Fourier transform infrared, scanning electron microscopy, X- ray photoelectron spectroscopy and surface area and pore analysis results indicated that the robust pure and N- doped carbon bodies have high surface area values in low volumes constructed by carbon layers with turbostratic structure. As the N-doped 3D carbon sample shows a surface area of 27.83 m 2 in a 0.221 cm 3 volume. Moreover, the 3D monolithic carbon bodies are porous materials with large pore volume up to 2.1 cm 3 /g which can be used in various practical applications. 1. Introduction 3D Monolithic high surface area materials are of great technological importance due to their various applications in industries. For instance, 3D carbon materials composed of graphene/graphene-like walls have been used in different devices for the energy applications such as supercapacitor, battery, fuel cell and solar cell electrodes [1–6]. They have also been used as catalysts, pollutant remediation agents, gas absorber/storage and bio/sensors, etc [7–11]. This is due to the unique carbon properties such as high electronic conductivity, huge surface area value and porosity as well as excellent chemical/electrochemical stability [1,5,12]. Of course, for a specifc application, some modifca- tion must be done on the carbon structure and morphology. For example, heteroatom doping the carbon materials could result in an increase in its performance for catalysis applications and it also could improve its capacitive capacity in supercapacitors [6,13–15]. On the other hand, due to the surface related applications of carbon materials, getting the highest possible value of the accessible surface area (ASA), is a key factor in the task performance [2,5,12,16]. Moreover, for most applications of the 3D bulk carbon materials such as the electrodes of the energy storage and conversion as well as gas storage devices, the pres- ence of open channels throughout the 3D bulk material is necessary, due to the electrolyte ions and gas transfer. Accordingly, some innovative synthesis/fabrication methods have been utilized to produce 3D monolithic carbon and heteroatom doped carbon materials with high ASA value and open channels [2,5,16–18]. Owning to the production of the 3D bulk carbon monoliths, the researchers have mostly used two methods including: (I) self-assembled graphene hydrogels/aerogels with physical inter-sheet cross-links, prepared by using a hydrothermal pro- cess of the graphene oxide (GO) dispersions in water, reduction of the GO sheets and formation of a 3D random stacking foam with weak physical inter-planar van der Waals force [7,17,19,20]. Also, some other authors have used a chemical cross-link agent during the formation of graphene hydrogels for the reinforcement of the mechanical properties and the conductivity enhancement of the 3D materials [3,19,21]. (II) template negative replica methods by using the CVD or wet chemical approaches [3,12,22,23]. In this method, a carbonaceous source is introduced inside the voids of a 3D porous solid template (or infltration of graphene) and after pyrolysis of the carbon source and formation of a 3D graphene foam, the solid template is then removed by an etching * Corresponding author. E-mail addresses: m.yeganeh@malayeru.ac.ir, yeganehghotbi@gmail.com (M. Yeganeh Ghotbi). Contents lists available at ScienceDirect Microporous and Mesoporous Materials journal homepage: http://www.elsevier.com/locate/micromeso https://doi.org/10.1016/j.micromeso.2019.109791 Received 29 July 2019; Received in revised form 28 September 2019; Accepted 2 October 2019