Study on Pd functionalization of microcantilever for hydrogen detection promotion

An absorption-actuated cantilever sensor often suffers from the severe problem of interface sliding between the functionalization coating and the cantilever surface due to overlying structural expansion of the surface coating. In this work, the microcantilever with Pd functionalization was employed for hydrogen detection. Two effects of Pd deposition technique and cantilever surface design were first contributed towards the effective Pd functionalization for superior hydrogen sensing performance. Experimental results indicated that the sputtering deposition technique benefited the Pd functionalization with compact structure and preferable adhesion for efficient sensing transduction. Surface design via trench modification could further provide the effective interlocking of Pd functionalization with the cantilever surface. For hydrogen detection, the Pd-functionalized cantilever with trench modification showed the superior sensing characteristics with higher sensitivity and a lower detection limit.