Sandia National Laboratories, Advanced Materials Laboratory, 1001 University Boulevard SE, Albuquerque, New Mexico 87106, USA.
Dalton Trans. 2012 Aug 21;41(31):9349-64. doi: 10.1039/c2dt30772c. Epub 2012 Jul 4.
A series of tin(II) amide alkoxides ((OR)Sn(NMe(2))) and tin(II) alkoxides (Sn(OR)(2)) were investigated as precursors for the production of tin oxide (SnO(x)) nanowires. The precursors were synthesized from the metathesis of tin dimethylamide (Sn(NMe(2))(2)) and a series of aryl alcohols {H-OAr = H-OC(6)H(4)(R)-2: R = CH(3) (H-oMP), CH(CH(3))(2) (H-oPP), C(CH(3))(3) (H-oBP)] or [H-OC(6)H(3)(R)(2)-2,6: R = CH(3) (H-DMP), CH(CH(3))(2) (H-DIP), C(CH(3))(3) (H-DBP)]}. The 1:1 products were all identified as the dinuclear species (OAr)Sn(μ-NMe(2)) where OAr = oMP (1), oPP (2), oBP (3), DMP (4), DIP (5), DBP (6). The 1:2 products were identified as either a polymer (Sn(μ-OAr)(2) (where OAr = oMP (7), oPP (8)), dinuclear (OAr)Sn(μ-OAr) (where OAr = oBP (9), DMP (10) or DIP/HNMe(2) (11)), or mononuclear [Sn(DBP)(2)] (12) complexes. These novel families of compounds (heteroleptic 1-6, and homoleptic 7-12) were evaluated for the production of SnO(x) nanowires using solution precipitation (SPPT; oleylamine/octadecene solvent system) or electrospinning (ES; THF solvent) processing conditions. The SPPT route that employed the heteroleptic precursors yielded mixed phases of Sn(o):romarchite [1 (100:0); 2 (80:20); 3 (68:32); 4 (86:14); 5 (66:35); 6 (88:12)], with a variety of spherical sized particles [1 (350-900 nm); 2 (150-1200 nm); 3 (250-950 nm); 4 (20-180 nm); 5 (80-400 nm); 6 (40-200 nm)]. For the homoleptic precursors, similar phased [7 (80:20); 8 (23:77); 9 (15:85); 10 (34:66); 11 (77:23); 12 (77:23)] spherical nanodots were isolated [7 (50-300 nm); 8: (irregular); 10 (200-800 nm); 11 (50-150 nm); 12 (50-450 nm)], except for 9 which formed polycrystalline rods [Sn(o):romarchite (15:85)] with aspect ratios >100. From ES routes, the heteroleptic species were found to form 'tadpole-shaped' materials whereas the homoleptic species formed electrosprayed nanodots. The one exception noted was for 7, where, without use of a polymer matrix, nanowires of Sn(o), decorated with micron sized 'balls' were observed. Due to the small amount of material generated, PXRD patterns were inconclusive to the identity of the generated material; however, cyclic voltammetry on select samples was used to tentatively identify the final Sn(o) (from 7) with the other sample identified as SnO(x) (from 1).
一系列锡(II)酰胺烷氧基化合物[(OR)Sn(NMe(2))](n)和锡(II)烷氧基化合物[Sn(OR)(2)](n)被研究用作氧化锡(SnO(x))纳米线生产的前体。前体是通过锡二甲酰胺[Sn(NMe(2))(2)]和一系列芳醇{H-OAr = H-OC(6)H(4)(R)-2:R = CH(3)(H-oMP),CH(CH(3))(2)(H-oPP),C(CH(3))(3)(H-oBP)]或[H-OC(6)H(3)(R)(2)-2,6:R = CH(3)(H-DMP),CH(CH(3))(2)(H-DIP),C(CH(3))(3)(H-DBP)]的复分解反应合成的。1:1 产物均被鉴定为双核物种[(OAr)Sn(μ-NMe(2))](2),其中 OAr = oMP(1),oPP(2),oBP(3),DMP(4),DIP(5),DBP(6)。1:2 产物被鉴定为聚合物[Sn(μ-OAr)(2)](∞)(其中 OAr = oMP(7),oPP(8)),双核[(OAr)Sn(μ-OAr)](2)(其中 OAr = oBP(9),DMP(10)或 DIP/HNMe(2)(11)),或单核[Sn(DBP)(2)](12)配合物。这些新型化合物家族(杂配体 1-6 和同配体 7-12)通过溶液沉淀(SPPT;油胺/十八烯溶剂体系)或静电纺丝(ES;THF 溶剂)处理条件来评估 SnO(x)纳米线的生产。采用杂配体前体的 SPPT 路线得到了 Sn(o):romarchite [1(100:0);2(80:20);3(68:32);4(86:14);5(66:35);6(88:12)]的混合相,具有各种球形尺寸的颗粒[1(350-900nm);2(150-1200nm);3(250-950nm);4(20-180nm);5(80-400nm);6(40-200nm)]。对于同配体前体,类似的相[7(80:20);8(23:77);9(15:85);10(34:66);11(77:23);12(77:23)]的球形纳米点被分离出来[7(50-300nm);8:(不规则);10(200-800nm);11(50-150nm);12(50-450nm)],但 9 形成了多晶棒[Sn(o):romarchite(15:85)],纵横比>100。从 ES 路线中,发现杂配体物种形成了“蝌蚪状”材料,而同配体物种形成了电纺纳米点。唯一的例外是 7,其中,在没有使用聚合物基质的情况下,观察到 Sn(o)纳米线,其表面装饰有微米大小的“球”。由于生成的材料数量较少,PXRD 图谱无法确定生成材料的身份;然而,对选定样品进行的循环伏安法被用于初步确定最终 Sn(o)(来自 7),而其他样品被鉴定为 SnO(x)(来自 1)。