Preparation of spindle-shaped polyaniline supported Au catalysts with enhanced catalytic reduction of 4-nitrophenol

Insights into the interaction between PANI and Au NPs of magnetic core‐shell Fe3O4/PANI/Au catalysts with remarkable catalytic performance in 4‐NP reduction

“…In previous works, Dai and coworkers confirmed the existence of partially negatively charged Au δ− (0 < δ < 1) because of the electronic transfer in PANI‐modified TiO 2 /Au catalysts 17 . The negative shift compared with 84.0 eV of Au 0 was usually regarded as a result of the electronic interaction between Au and PANI 14 . However, in this paper, the negative shift in BE value of Au is very small and the electronic interaction between Au and PANI in Fe 3 O 4 /PANI/Au(Sol) before used may be weak.…”

“…The k ′ is calculated as 303.04 and 145.87 s −1 ·g Au −1 for Fe 3 O 4 /PANI/Au(Sol) and Fe 3 O 4 /PANI/Au(In Situ), which is higher than that of polystyrene/PANI/Au (Au size 10–100 nm, Au loading 4.59 wt%), 13 Fe 3 O 4 @Au‐PANI (Au size 15 nm, Au loading 15.547 wt%), 34 and PANI@magnetic graphene oxide/Au (Au size 5 nm, Au loading 2.365 wt%) 35 . The k ′ of Fe 3 O 4 /PANI/Au(Sol) is the highest among the seven kinds catalysts listed in Table 1, which is nearly 1.7 times the value of PANI(Spindle‐shaped)/Au with the same gold loading (0.498%) and similar Au size (2–6 nm) 14 . The k ′ of Fe 3 O 4 /PANI/Au(In Situ) (Au size 30–80 nm, Au loading 0.4997 wt%) is 1.9 times the value of PANI microtubes supported Au catalysts (Au size 6–16 nm, Au loading 0.498 wt%) prepared by in situ reduction method 28 .…”

“…The gold sol adsorption and the redox reaction between Au ions and PANI carrier were employed for the Au loading on Fe 3 O 4 /PANI. The gold sol (29.4 mg/mL) was freshly prepared according to the literature before used 14 . Fe 3 O 4 /PANI core‐shell composites (0.2 g) and gold sol (33.9 mL) was mixed together and stirred mechanically for 24 h at low speed.…”

“…PANI has been paid attention recently as the gold catalysts support because of its easy synthesis, distinctive synergistic effects, and excellent stabilization for gold NPs. In favor of the special chemical or physical nature of PANI, the PANI carried gold catalysts can be synthesized by the redox reaction between gold precursors and PANI (or aniline monomer) 13 or by the adsorption between gold sol and the PANI support 14 . It was reported that the imine sites (N + H) of protonated or doped PANI could absorb the gold ions (AuCl 4 − ) and reduced them in situ to obtain small and stable gold NPs 15 .…”

Comprehensive Experiment of Preparation of PANI Supported Nano Au Catalysts and the Study of Catalytic Properties

“…作为地方综合性大学，烟台大学一直致力于服务地方经济的发展。鉴于烟台市黄金之乡的产业 优势，烟台大学成立了山东省黄金工程技术研究中心。中心致力于高附加值的黄金催化剂的研究开 发，以加快黄金功能材料的产业化速度，打造黄金经济新增长点。团队研发的铝基YD-2系列催化剂 已成功实现产业化，且被金催化创始人Masatake Haruta教授评述为长寿命金催化剂的典型案例 [1] 。团 队近年来致力于新型纳米金催化剂的研发，发现导电聚合物PANI负载的纳米金催化剂具有优异的反 应活性和稳定性 [2][3][4] 。 为加快工程教育专业认证进度，烟台大学化学化工学院从成果导向教育(OBE)的角度出发，鼓励 教师进行综合实验改革，从学生需要获得的能力出发，倒推实验改革，将较为成熟的、具有一定创 新性的前沿科研成果改造优化为综合实验，以适应OBE教学理念的要求，为社会培养更多合格的专 业技术人才。在学院的支持下，应用化学教研室持续推进实验教学改革，先后优化或结合教师科研 课题开设了多个综合实验项目，获得了较好的教学效果 [5][6][7][8] 。近年来，科研转化实验成为本科教学实 验改革与更新的重要来源，对于拓宽学生的学术视野、培养学生的科研素养具有重要作用 [9][10][11][12] [13] 。以UV-Vis监测反应过程中4-NP的吸光度变化，对各催化剂进行活性评价。具体流程如下 [4] ： 在烧瓶中，依次加入5.5 mL 4-NP溶液(5.43 × 10 −3 mol•L −1 ，学生配制)、15 mL水、0.17 g NaBH 4 ，溶 液变为亮黄色。磁力搅拌下，加入0.01 g待评价催化剂，随着反应的进行，在一定时间间隔内，用微 升计取0.5 mL反应液于5 mL的注射器中，经滤芯过滤于10 mL的样品管中。将所得液体加5 mL水稀 释后，采用紫外分光光度计记录UV-Vis谱图，直至溶液变为无色。…”