Yongming Fan

Valorization of bamboo by γ-valerolactone/acid/water to produce digestible cellulose, degraded sugars and lignin

A novel pretreatment process was developed to achieve valorization of bamboo components into digestible cellulose, degraded sugars and lignin. In this case, bamboo was pretreated with 60% γ-valerolactone (GVL)/40% water containing 0.05mol/L H2SO4, yielding solid fraction rich in cellulose. The resulting liquor was further treated with the addition of NaCl and ultrasound, resulting in water phase rich in degraded sugars and GVL phase containing lignin, which was easy to recover. Results showed that the enzymatic hydrolysis was enhanced by 6.7-fold after treatment as compared to the control. The degraded sugars released in water phase contained monosaccharides (70.72-160.47g/kg) together with oligo- and polysaccharides (46.4-181.85g/kg). The lignin obtained had high purity, low molecular weight (1820-2970gmol-1) and low polydispersity (1.93-1.98). The present study creates a novel pretreatment process for the conversion of Gramineae biomass into useful feedstocks with potential applications in the fields of fuels, chemicals and polymers.

Facile synthesis of urchin-like RuCu and hollow RuCuMo nanoparticles and preliminary insight to their formation process by cyclic voltammetry

Urchin-like RuCu nanoparticles and hollow RuCuMo nanoparticles were prepared by a one-pot chemical reduction method. The nanoparticles were characterized by EDX, HRTEM, XPS and ICP-AES. By combining cyclic voltammetry and TEM, the formation process of nanoparticles was obtained. The urchin-like RuCu nanoparticles are proved to be formed via underpotential deposition mechanism and the formation of ternary nanoparticles RuCuMo was due to the replacement of Cu with Ru and the interception of Mo gradually. It was found that the formation of different morphology is depended on the precursors in the reaction system and their reduction sequences. Compared to previously reported multi-step synthetic routes, the developed method here is much simpler.

Lignin-based highly sensitive flexible pressure sensor for wearable electronics

The development of flexible sensors with low cost, facile preparation and good reproducibility is of profound significance for wearable electronics and intelligent systems. Lignin is an aromatic composition of lignocellulosic biomass and known as a cheap, renewable, and environmentally friendly resource available everywhere. In this study, we present a simple and low-cost approach for the preparation of a highly electrically sensitive and flexible composite with polydimethylsiloxane and carbonized lignin via a facile process (CL/PDMS). This electrically sensitive flexible composite can be used in the preparation of a piezo-resistive sensor, which exhibits stable and fast response to loading and unloading stress in 60 ms and 40 ms, respectively. The sensor prototype displayed high sensitivity (57 kPa−1), wide range of working pressure (from 0 to 130 kPa) and excellent durability. The signals of pulse rates and the force needed for picking up items were successfully collected with this CL/PDMS sensor prototype. With the simple process for fabrication, low-cost of the filling material and excellent performance, we believe that the lignin-based sensitive flexible composite CL/PDMS is promising for applications in wearable electronics and intelligent systems such as health monitoring, smart skins, sports and other related areas.