Magnesium oxysulfate(MOS)whiskers are commonly synthesized through a dissolution-precipitation mechanism,wherein Mg(OH)_(2)dissolves to form Mg(OH)_(6)^(4−),followed by reactions with SO_(4)^(2−)and H_(2)O to yield MO...Magnesium oxysulfate(MOS)whiskers are commonly synthesized through a dissolution-precipitation mechanism,wherein Mg(OH)_(2)dissolves to form Mg(OH)_(6)^(4−),followed by reactions with SO_(4)^(2−)and H_(2)O to yield MOS whiskers.However,the impact of Mg(OH)_(2)precursor properties on the formation process of MOS whiskers has been insufficiently explored,and sector-like and needle-like morphologies were both observed in previous studies.In this study,we systematically investigated how the properties of Mg(OH)_(2)precursors influenced the crystalline structure and morphology of MOS whiskers.Under various experimental conditions,MgSO_(4)·5Mg(OH)_(2)·2H_(2)O(152MOS)whiskers were consistently obtained,regardless of Mg(OH)_(2)morphology and size.The size of Mg(OH)_(2)emerged as a critical factor in shaping the morphology of 152MOS whiskers.Smaller-sized Mg(OH)_(2)(≤106±37 nm)favored the formation of sector-like whiskers,while larger-sized Mg(OH)_(2)(≥206±98 nm)encouraged the development of needle-like whiskers.This distinction was attributed to the slower dissolution rate exhibited by larger-sized Mg(OH)_(2),maintaining a smaller number of 152MOS nuclei and promoting the growth of needle-like whiskers instead of the aggregation of 152MOS nuclei into sector-like structures.In addition,the effects of the molar ratio of Mg^(2+)to SO_(4)^(2−)and hydrothermal temperature were also studied.The average length and diameter of the needle-like whiskers prepared with Mg(OH)_(2)of 331±145 nm under optimized conditions were 77±32 and 0.39±0.10μm,respectively.This study presented an effective strategy for controlling the morphology of 152MOS whiskers.展开更多
基金the National Natural Science Foundation of China(grant Nos.22178336,21991103)is gratefully acknowledged.
文摘Magnesium oxysulfate(MOS)whiskers are commonly synthesized through a dissolution-precipitation mechanism,wherein Mg(OH)_(2)dissolves to form Mg(OH)_(6)^(4−),followed by reactions with SO_(4)^(2−)and H_(2)O to yield MOS whiskers.However,the impact of Mg(OH)_(2)precursor properties on the formation process of MOS whiskers has been insufficiently explored,and sector-like and needle-like morphologies were both observed in previous studies.In this study,we systematically investigated how the properties of Mg(OH)_(2)precursors influenced the crystalline structure and morphology of MOS whiskers.Under various experimental conditions,MgSO_(4)·5Mg(OH)_(2)·2H_(2)O(152MOS)whiskers were consistently obtained,regardless of Mg(OH)_(2)morphology and size.The size of Mg(OH)_(2)emerged as a critical factor in shaping the morphology of 152MOS whiskers.Smaller-sized Mg(OH)_(2)(≤106±37 nm)favored the formation of sector-like whiskers,while larger-sized Mg(OH)_(2)(≥206±98 nm)encouraged the development of needle-like whiskers.This distinction was attributed to the slower dissolution rate exhibited by larger-sized Mg(OH)_(2),maintaining a smaller number of 152MOS nuclei and promoting the growth of needle-like whiskers instead of the aggregation of 152MOS nuclei into sector-like structures.In addition,the effects of the molar ratio of Mg^(2+)to SO_(4)^(2−)and hydrothermal temperature were also studied.The average length and diameter of the needle-like whiskers prepared with Mg(OH)_(2)of 331±145 nm under optimized conditions were 77±32 and 0.39±0.10μm,respectively.This study presented an effective strategy for controlling the morphology of 152MOS whiskers.
