Highly mass activity electrocatalysts with ultralow Pt loading on carbon black for hydrogen evolution reaction

Pt-based nanocatalysts offer excellent prospects for various industries.However,the low loading of Pt with excellent performance for efficient and stable nanocatalysts still presents a considerable challenge.In this study,nanocatalysts with ultralow Pt content,excellent performance,and carbon black as support were prepared through in-situ synthesis.These~2-nm particles uniformly and stably dispersed on carbon black because of the strong s-p-d orbital hybridizations between carbon black and Pt,which suppressed the agglomeration of Pt ions.This unique structure is beneficial for the hydrogen evolution reaction.The catalysts exhibited remarkable catalytic activity for hydrogen evolution reaction,exhibiting a potential of 100 mV at 100 mA·cm^(-2),which is comparable to those of commercial Pt/C catalysts.Mass activity(1.61 A/mg)was four times that of a commercial Pt/C catalyst(0.37 A/mg).The ultralow Pt loading(6.84wt%)paves the way for the development of next-generation electrocatalysts.

Efficacy and safety of light therapy for Parkinson disease

To the Editor:Parkinson disease(PD)is the second most common neurodegenerative disorder associated with significant disability and negative impact on quality of life(QoL),affecting 2%to 3%of the population≥65 years of age.^([1])Although the disorder is defined by motor features including asymmetric tremor,bradykinesia,and rigidity,various non-motor features are typically seen,including cognitive impairment,depression,sensory symptoms,autonomic dysfunction,and sleep disturbances.Due to the complexity,PD is challenging to treat.There are currently no effective treatments to prevent or halt the progression of PD.

Degradation of trace nitrobenzene in water by microwave-enhanced H2O2-based process

To evaluate possible use of microwave- enhanced H2O2-based （MW/H2O2） process to degrade trace nitrobenzene （NB） in water, a series of batch experiments were conducted. The results showed that 2450MHz microwave irradiation significantly enhanced oxidative decomposition of nitrobenzene （NB） in a H2O2 system. About 90% NB was degraded by the MW/H2O2 process in 30 min. Moreover, the MW/H2O2 process could enhanced the oxidative degradation of NB even at relatively low temperature （50℃）. When the initial concentration of NB was 300gg/L, the optimum ratio of H2O2 to NB and MW power were 70 and 300W respectively. The presence of humic acid significantly increased H2O2 dosage. The ultraviolet absorbance at 254 nm （UV254） indicated degradation of NB was stepwise and some intermediates were produced. The gas chromatography-mass spectrometric （GC-MS） analysis showed that main intermediates were nitrophenolic and carbonyl compounds.