Photoreforming is a process that harnesses the redox ability of photocatalysts upon illumination, to simultaneously drive the reduction of H+ into hydrogen gas and oxidation of organic compounds. Over the...

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Photoreforming is a promising alternative to water splitting for H 2 generation due to the favorable organic oxidation half-reaction and the potential to simultaneously produce solar fuel and value-added chemicals. Recently, carbon nitride has received significant attention as an inexpensive photocatalyst for the photoreforming process. However, the application of carbon nitride continues to be hampered by its poor photocatalytic performance. Herein, we report for the first time a synergistic modification of an in situ photodeposited Ni cocatalyst on carbon nitride via cyanamide functionalization and solid/liquid interfacial charge-induced activation using excess Ni 2+ ions. Synergism between the cyanamide functionalization and charge-induced activation by the excess Ni 2+ ions invokes enhanced activity, selectivity, and stability during ethanol photoreforming. A H 2 evolution rate of 2.32 mmol h −1 g −1 in conjunction with an acetaldehyde production rate of 2.54 mmol h −1 g −1 was attained for the Ni/NCN-CN. The H 2 evolution rate and elevated acetaldehyde selectivity (above 98%) remained consistent under prolonged light illumination. To understand the origin of the complementary promotional effects, the contributions of cyanamide groups and excess Ni 2+ ions to selective ethanol photoreforming are decoupled and systematically investigated. The cyanamide functionality on carbon nitride was found to promote hole scavenging for the ethanol oxidation reaction, thereby enabling effective electron transfer to the Ni cocatalyst for H 2 evolution. Concomitantly, excess Ni 2+ ions remaining in solution created a positively charged environment on the photocatalyst surface, which improved charge carrier utilization and ethanol adsorption. The work highlights the importance of both carbon nitride functionality and charge on the photocatalyst surface in developing a selective photocatalytic reforming system.

Yarn dyed wastewater has to be treated prior to disposal into the water bodies due to its high content of harmful organic compounds. In this study, the performance of Chemical Oxygen Demand (COD) removal and kinetic rate constant are investigated via hybrid electrocoagulation-Fenton in a continuous system using wastewater discharged from a yarn dyed industry in Surabaya city. The wastewater was treated in a batch mode using electrocoagulation to reduce Total Suspended Solid, followed by Fenton method in a continuous system to reduce COD level. Various Fe(II) feeding modes, molar ratio of Fe(II)/H2O2, initial pH of wastewater, and flow rate are used in this study. The results show that COD removal process obeys a pseudo-first order kinetics. At Fe(II)/H2O2 ratio of 1:10, initial wastewater pH of 3.0, and feed flow rate of 30 mL/min, the COD removal efficiency was observed to be 80%, and the kinetic rate constant is 0.07046 min-1. The chemical cost for the treatment estimated to be IDR 160 per L wastewater, which is cheaper than the previously reported batch system of IDR 256/L.

COVID-19 has disrupted all aspects of human life. To mitigate the impact of the pandemic, several efforts have been taken, including by Indonesian scholars abroad. This book entitled Indonesia Post-Pandemic Recovery Outlook: Strategy towards Net-Zero Emissions by 2060 from the Renewables and Carbon-Neutral Energy Perspectives explores energy sustainability and climate change issues and how it can progress further. There are also discussion on the delays caused by the COVID-19 pandemic to a few major renewable energy projects that should have been done in 2020-2021. Comprising of 14 chapters, this book is divided into three sections. The first part, Indonesia's Current Position and Strategy for Renewable Energy, explores Indonesia's current position and strategy on New and Renewable Energy. This chapter also explores Indonesia's commitment towards Net-Zero Carbon Emission 2060. Second, Carbon-Free and Renewable Energy in Indonesia, discusses the status of renewable energy use in the world, elaborate on the carbon impact of energy shift from fossil to renewable sources, and introduce a new criterion in renewable energy: carbon-neutral energy. The last part, Indonesia's New Strategy to Achieve Net-Zero Emission in 2060, explores the macroeconomic benefits of renewable and carbon-neutral energy deployment which are increasing energy security, fueling GDP development, creating job opportunities, enhancing human welfare, and achieving gender equality. We hope that this book can be a valuable reference for stakeholders, policymakers, as well as society to recover from the pandemic crisis and find better solutions to benefit future generations.