在碳纤维上采用三脉冲电沉积的方法制备出钯银合金纳米粒子链.把表面覆盖有Pd-Ag合金纳米粒子链的碳纤维组装成氢气传感器.采用扫描电子显微镜(SEM)和X射线能谱(EDX)表征了合金纳米粒子链的形貌和成分,应用CHI660B电化学工作站测试其氢传感性能.结果表明,在钯、银离子摩尔比为15∶1的电解液中,在-1.0--1.5 V下,成核5-40 ms; 在-0.25--0.35 V,生长200-300 s的条件下,即可获得银的质量分数为16.0%-25.0%的钯银合金纳米粒子链阵列.在室温下,传感器对在0.30%-5.00%(φ,体积分数,下同)范围内的氢气有响应,最快响应时间约为300 s,灵敏度最高可达31.0%; 氢在0.30%-1.20%的范围内响应电流与氢气浓度成线性关系,超过4.00%时响应电流不再随浓度的增加而变化; 在低于3.50%的浓度下氢传感器的重现性良好.
Pd-Ag alloy nanoparticle chains were fabricated on carbon fibers using three-pulse electrodeposition method.Pd-Ag alloy nanoparticle chains on carbon fiber surfaces can be used as hydrogen sensors.Scanning electron microscopy(SEM) and X-ray spectroscopy(EDX) were used to characterize the morphology and composition of the alloy nanoparticle chains.A CHI660B electrochemical workstation was used to evaluate the hydrogen sensing ability.Results show that Pd-Ag alloy nanoparticle chain arrays with a silver content of 16.0%-25.0%(w) were obtained in the electrolyte with an ion concentration ratio(molar ratio) of palladium to silver of 15∶1.At-1.0--1.5 V nucleation took place within 5-40 ms and at-0.25--0.35 V growth was allowed for 200-300 s.The sensors responded to hydrogen gas at concentrations of 0.30%-5.00%(φ,volume fraction) at room temperature.The fastest response time was about 300 s and 31.0% sensitivity was obtained.The response current was linearly proportional to the hydrogen concentrations from 0.30% to 1.20%(φ).The current signal did not change with the hydrogen concentration larger than 4.00%.These hydrogen sensors show good reproducibility at hydrogen concentrations lower than 3.50%.