TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preparation (Claimed): Preparation of (I) comprises: either reacting graphene oxide with a silane agent including N-(trimethoxysilylpropyl)ethylene diamine triacetic acid or its trisodium salt to give (I), where the ratio of the basic graphene oxide unit: N-(trimethyoxypropyl)ethylenediamine triacetic acid or its sodium salt is 1:0.00001 to 1:0.5; or optionally treating graphene oxide with thionyl chloride or thionyl bromide to convert carboxyl groups on the surface of the graphene oxide to corresponding -C(=O)Cl groups or -C(=O)Br groups and reacting the obtained graphene oxide with AB1 to produce (I), where A is HO-(CH2)m- (preferred), H-NH-, H-S-, R1-O-Si(-OR1)2(-CH2)m-, HO-C(=O)-, HO-C(=O)-O-, HO-C(=O)-O(CH2)m-, HO-C(=O)-NH-,HO-C(=O)-NH-(CH2)m- or HO-P(=O)2-O-. Preferred Components: The AB1 is N-(trimethoxysilylpropyl)ethylenediamine triacetic acid or its salt. The graphene oxide contains functional groups -COOH, -OH (both preferred) and -O-. The ratio of basic graphene oxide units to x is 1:0.00001 to 1:0.04. Preferred Definitions:    A = -(CH2)m- or -O-Si(-OR1)2(-CH2)m-;    B1 = ethylene diamine triacetic acid, nitrilo diacetic acid, diethylene triamine tetraacetic acid, ethylene glycol triacetic acid, diethylene triamine or their salts; and    m = 1-4.    EXAMPLE - Graphite powder (0.1 g, 0.5 g, 1 g, 5 g and 10 g) was first treated with a solution of concentrated sulfuric acid (1, 5, 10, 50 and 100 ml), potassium persulfate (20 g) and phosphorus pentoxide (2, 5, 10, 15 and 20 g). The mixture was kept at 20-90 degrees C for 1-24 hours using a hotplate. The mixture was cooled to room temperature and diluted with deionized water (100 ml, 250 ml, 500 ml, 1 l and 2 l) and left overnight at room temperature. The mixture was further worked up to give pre-treated or pre-oxidized graphite. The pre-treated graphite powder was added into cold concentrated sulfuric acid (1 ml, 5 ml, 10 ml, 20 ml and 50 ml). Then potassium permanganate (0.1 g, 0.5 g, 1 g, 5 g and 50 g) was added under stirring and the temperature of the mixture was kept below 20 degrees C by cooling. The mixture was then stirred at 35 degrees C for 4 hours and then diluted with deionized water (10, 50, 100, 200 and 500 ml), where the dilution was carried out in ice bath to keep the temperature below 40-50 degrees C. After adding deionized water, the mixture was stirred for 30 minutes to 21 hours and then additional deionized water (50, 250, 1000 and 2500 ml). 30% Hydrogen peroxide (1, 5, 10, 20 and 50 ml) was added to the mixture and the mixture was further worked up to give graphene oxide powder. The obtained graphene oxide powder (1, 2, 5, 10 and 100 mg) was added into a flask containing ethanol (10, 20, 50, 100 and 500 ml) and dispersed into ethanol using ultrasonication for 1-60 minutes. 0.1-15% Hexane (1-50 ml), acetonitrile and ethanol solution of N- (trimethoxysilylpropyl) ethylenediamine triacetic acid or its sodium salt was added and stirred for 1-48 hours at 30-85 degrees C to complete silylation of graphene oxide. After the reaction was completed, 100 ml of water, ethanol and methanol were added to dilute the unreacted silane molecules to obtain ethylenediamine triacetic acid graphene oxide, which was filtered, washed with methanol and water and dried.