In this study, palladium particles supported on carbon black (Vulcan XC-72) (Pd/C) and corncob biochar (Pd/CB800, Pd/CB900, and Pd/CB1000) were successfully synthesized using borohydride reduction. The biochar support was obtained from corncob waste via pyrolysis from 800 to 1000°C. Scanning electron microscopy with energy dispersive x-ray (SEM–EDX) revealed successful deposition of Pd metal particles on the carbon support materials. X-ray diffraction (XRD) analysis confirmed the crystalline structures of Pd, and the crystallite size was found to be smallest in Pd/CB900. The electrocatalytic activity of the Pd electrocatalyst composites towards ethanol oxidation reaction (EOR) in an alkaline medium was investigated using cyclic voltammetry (CV). CV analysis has shown that Pd/CB900 gave the least positive onset potential (E_onset = −0.587 ± 0.0065 V), highest electrochemically active surface area (EASA = 31.51 ± 2.24 m²·g⁻¹), and highest anodic peak current density (I_f = 20.77 mA·cm⁻²) compared with Pd/CB800, Pd/CB1000, and Pd/C. Furthermore, the Tafel plot and chronoamperometry have shown that Pd/CB900 exhibited faster kinetics (Tafel slope = 297.6 ± 4.62 mV·dec⁻¹) and durability (% current retention = 50.64 ± 2.99%) than Pd/C towards EOR in an alkaline medium. This study highlights the simple and straightforward synthesis of the anode electrocatalyst material for direct ethanol fuel cell application.

中文翻译：

---

玉米芯生物炭负载钯电催化剂增强碱性介质中乙醇氧化反应的电催化活性

在本研究中，采用硼氢化物还原成功合成了炭黑（Vulcan XC-72）（Pd/C）和玉米芯生物炭（Pd/CB800、Pd/CB900 和 Pd/CB1000）负载的钯颗粒。生物炭载体是通过 800 至 1000°C 的热解从玉米芯废物中获得的。能量色散 X 射线扫描电子显微镜 (SEM-EDX) 显示 Pd 金属颗粒成功沉积在碳载体材料上。X 射线衍射 (XRD) 分析证实了 Pd 的晶体结构，发现 Pd/CB900 中的微晶尺寸最小。使用循环伏安法（CV）研究了Pd电催化剂复合材料在碱性介质中对乙醇氧化反应（EOR）的电催化活性。CV 分析表明，Pd/CB900 具有最小的正起始电位 (E _onset  = -0.587 ± 0.0065 V)、最高的电化学活性表面积 (EASA = 31.51 ± 2.24 m ² ·g ^-1 ) 和最高的阳极峰值电流密度(I _f  = 20.77 mA·cm ^-2 )与Pd/CB800、Pd/CB1000和Pd/C相比。此外，塔菲尔图和计时电流分析法表明，在碱性溶液中，Pd/CB900 比 Pd/C 表现出比 Pd/C 更快的动力学（塔菲尔斜率 = 297.6 ± 4.62 mV·dec ^-1）和耐久性（% 电流保留 = 50.64 ± 2.99%）中等的。这项研究强调了用于直接乙醇燃料电池应用的阳极电催化剂材料的简单直接的合成。