Abstract: An oil-based drilling fluid and method of preparing an oil-based drilling fluid are disclosed. The oil-based drilling fluid comprising a base oil continuous phase, an aqueous discontinuous phase, and at least one rheology modifier. The at least one rheology modifier including an alkaline-earth diamondoid compound. The method of preparing the oil-based drilling fluid including mixing a base oil, at least one emulsifier, and at least one wetting agent to form a first mixture, adding and mixing at least one rheology modifier into the first mixture to form a second mixture, adding and mixing at least one fluid-loss control additive into the second mixture to form a third mixture, adding and mixing a brine solution into the third mixture to form a fourth mixture, and adding and mixing a weighting additive into the fourth mixture to form the oil-based drilling fluid.

Abstract: A method for preparing a magnesium adamantane carboxylate salt is provided. The method includes mixing a magnesium salt and a diamondoid compound having at least one carboxylic acid moiety to form a reactant mixture and hydrothermally treating the reactant mixture at a reaction temperature for a reaction time to form the magnesium adamantane carboxylate salt.

Abstract: Embodiments are directed to adamantane-intercalated layered double-hydroxide (LDH) particles and the methods of producing adamantane-intercalated LDH particles. The method comprises adding to an aqueous solution a first precursor and a second precursor to form an initial mixture, where the first precursor is Al(OH)3 or Al2O3, the second precursor is a hydroxide M(OH)2 or an oxide MO, where M is a metal of oxidation state +2; and the initial mixture has a M/Al molar ratio of from 1 to 5. The method also comprises adding to the initial mixture an amount of adamantane to form a reaction mixture having an Al/adamantane molar ratio of from 0.5 to 2; and heating the reaction mixture to produce adamantane-intercalated LDH particles, where the adamantane-intercalated LDH particles have aspect ratios greater than 100.

Abstract: A method for preparing a transition-metal adamantane carboxylate salt is presented. The method includes mixing a transition-metal hydroxide and a diamondoid compound having at least one carboxylic acid moiety to form a reactant mixture, where M is a transition metal. Further, the method includes hydrothermally treating the reactant mixture at a reaction temperature for a reaction time to form the transition-metal adamantane carboxylate salt.

Abstract: An oil-based drilling fluid and method of preparing an oil-based drilling fluid are disclosed. The oil-based drilling fluid comprising a base oil continuous phase, an aqueous discontinuous phase, and at least one rheology modifier. The at least one rheology modifier including an alkaline-earth diamondoid compound. The method of preparing the oil-based drilling fluid including mixing a base oil, at least one emulsifier, and at least one wetting agent to form a first mixture, adding and mixing at least one rheology modifier into the first mixture to form a second mixture, adding and mixing at least one fluid-loss control additive into the second mixture to form a third mixture, adding and mixing a brine solution into the third mixture to form a fourth mixture, and adding and mixing a weighting additive into the fourth mixture to form the oil-based drilling fluid.

Abstract: Embodiments of the present disclosure are directed towards methods for preparing mixed-metal oxide particles by heating adamantane-intercalated layered double-hydroxide (LDH) particles at a reaction temperature of from 400° C. to 800° C. to form mixed-metal oxide particles. The adamantane-intercalated LDH particles have a general formula [M1-xAlx(OH)2](A)x.mH2O, where x is from 0.14 to 0.33, m is from 0.33 to 0.50, M is chosen from Mg, Ca, Co, Ni, Cu, or Zn, and A is adamantane carboxylate, and an aspect ratio greater than 100. The aspect ratio is defined by the width of an adamantane-intercalated LDH particle divided by the thickness of the adamantane-intercalated LDH particle. The mixed-metal oxide particles comprise a mixed-metal oxide phase containing M, Al or Fe, and carbon.