Abstract Palladium is very expensive metal and has numerous applications especially as a versatile hydrogenation and dehydrogenation catalyst for chemical reactions. The main hurdle in its wide use is the high materials cost. In the present study a cost effective palladium nano catalyst was prepared using the green method of synthesis with guar gum as capping and reducing agent. The formations of palladium nanoparticles were confirmed by UV-spectrophotometer while for morphology and nature, SEM and XRD were performed that confirmed the crystalline nature of PdNPs and proved the roughly spherical shape of nanoparticles. FT-IR analysis showed different functional groups of reducing agent and proved that guar gum have the ability to stabilized as well as to reduce the Pd (II) to Pd (0). Specific signal for the palladium is present in EDX spectra that further confirmed the formation of PdNPs. The catalytic efficiency was studied using the hydrogenation of 4-nitrophenol. Rate constant of prepared nano-catalyst was 0.1436/min, its efficiency, TON, TOF, in above mention reaction is 90.83, 27.78, and 185.2/hrs, respectively. Data obtained proved synthesized PdNPs to be efficient heterogeneous catalyst for the reduction of 4-NP and for the degradation of azo dyes.

中文翻译：

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以瓜尔胶为稳定剂高效合成钯纳米颗粒及其在偶氮染料还原反应和降解中的应用

摘要 钯是一种非常昂贵的金属，用途广泛，特别是作为化学反应的通用加氢和脱氢催化剂。其广泛使用的主要障碍是高昂的材料成本。在本研究中，采用绿色合成方法，以瓜尔胶为封端剂和还原剂，制备了一种具有成本效益的钯纳米催化剂。通过紫外分光光度计确认钯纳米颗粒的形成，而对于形态和性质，进行了 SEM 和 XRD，证实了 PdNPs 的结晶性质并证明了纳米颗粒的大致球形。FT-IR分析表明还原剂具有不同的官能团，证明瓜尔豆胶具有稳定和将Pd（II）还原为Pd（0）的能力。EDX 光谱中存在钯的特定信号，进一步证实了 PdNP 的形成。使用4-硝基苯酚的加氢研究催化效率。制备的纳米催化剂的速率常数为0.1436/min，其在上述反应中的效率、TON、TOF分别为90.83、27.78和185.2/hrs。获得的数据证明合成的 PdNPs 是用于还原 4-NP 和降解偶氮染料的有效多相催化剂。